• Title/Summary/Keyword: Loss-differentiation

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The Hairless Gene: A Putative Navigator of Hair Follicle Development

  • Kim, Jeong-Ki;Kim, Bong-Kyu;Park, Jong-Keun;Choi, Jee-Hyun;KimYoon, Sung-Joo
    • Genomics & Informatics
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    • v.9 no.3
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    • pp.93-101
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    • 2011
  • The Hairless (HR ) gene regulates the expression of several target genes as a transcriptional corepressor of nuclear receptors. The hair follicle (HF), a small independent organ of the skin, resides in the epidermis and undergoes regenerative cycling for normal hair formation. HF development requires many genes and signaling pathways to function properly in time and space, one of them being the HR gene. Various mutations of the HR gene have been reported to cause the hair loss pheno-type in rodents and humans. In recent studies, it has been suggested that the HR gene is a critical player in the regulation of the hair cycle and, thus, HF development. Furthermore, the HR gene is associated with the Wnt signaling pathway, which regulates proliferation and differentiation of cells and plays an essential role in hair and skin development. In this review, we summarize the mutations responsible for human hair disorders and discuss the roles of the HR gene in HF development.

Wireless Measurement based TFRC for QoS Provisioning over IEEE 802.11 (IEEE 802.11에서 멀티미디어 QoS 보장을 위한 무선 측정 기반 TFRC 기법)

  • Pyun Jae young
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.4B
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    • pp.202-209
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    • 2005
  • In this paper, a dynamic TCP-friendly rate control (TFRC) is proposed to adjust the coding rates according to the channel characteristics of the wireless-to-wired network consisting of wireless first-hop channel. To avoid the throughput degradation of multimedia flows traveling through wireless lint the proposed rate control system employs a new wireless loss differentiation algorithm (LDA) using packet loss statistics. This method can produce the TCP-friendly rates while sharing the backbone bandwidth with TCP flows over the wireless-to-wired network. Experimental results show that the proposed rate control system can eliminate the effect of wireless losses in flow control of TFRC and substantially reduce the abrupt quality degradation of the video streaming caused by the unreliable wireless link status.

Effect of Water Extract of Aloe in RANKL-induced Osteoclast Differentiation (파골세포 분화에 미치는 노회(蘆會) 추출물의 효과)

  • Lee, Jeong-Hugh;Lee, Myeung-Su;Chae, Soo-Uk;Kim, Ha-Young;Moon, Seo-Young;Jeon, Byung-Hoon;Cho, Hae-Joong
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.25 no.6
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    • pp.1008-1013
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    • 2011
  • Osteoporosis is the leading underlying cause of fractures, particularly in postmenopausal women, due to the loss of estrogen-mediated suppression of bone resorption. More than 50% of adults 50 years of age or older are estimated to have osteoporosis. Osteoclast which is main target for treatment of osteoporosis is originated from hematopoietic cell line. Aloe has been widely used in worldwide country as a coadjuvant medicine. Extracts of the leaves of Aloe have been used in condition to improve dermatologic problem such as seborrheic dermatitis, aphthous stomatitis, xerosis, lichen planus and has been known to exert anti-inflammatory, anti-oxidant and anti-tumor effects. However, despite the popularity of aloe as a plant food supplements, the evaluation of its efficacy as a possible therapeutic option for osteoporosis remains scarce. Thus, we evaluated the effect of Aloe on receptor activator of nuclear factor-${\kappa}B$ ligand (RANKL)-induced osteoclast differentiation. Here we found that Aloe significantly inhibited osteoclast differentiation induced by RANKL. Aloe suppressed the activation of p38 pathway and $NF{\kappa}B$ in bone marrow macrophages (BMMs) treated with RANKL. Also, Aloe significantly inhibited the mRNA expression of c-Fos, tartrate-resistant acid phosphatase (TRAP), osteoclast-associated receptor (OSCAR), nuclear factor of activated T cells (NFAT)c1 and cathepsin K in BMMs treated with RANKL. Particularly, Aloe greatly inhibited the protein expression of c-fos and NFATc1. Taken together, our results suggested that Aloe may be useful tool for treatment of osteoporosis by inhibition of osteoclast differentiation.

Effect of Water Extract of Cynanchi Wilfordii Radix in RANKL-induced Osteoclast Differentiation (백하수오(白何首烏) 물 추출물의 파골세포 분화에 미치는 영향)

  • Ahn, Yong-Hwan;Oh, Jae-Min;Lee, Myeung-Su;Jung, Jong-Hyuk;Chae, Soo-Uk;Moon, Seo-Young;Jeon, Byung-Hoon;Choi, Min-Kyu
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.26 no.2
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    • pp.160-165
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    • 2012
  • Osteoporotic fracture became a serious social problem, which related with mortality and morbidity in old age population. Osteoclast which is responsible for bone resorption is originated from hematopoietic cell line and plays a key role osteoporotic bone loss. Cynanchum wilfordii (Asclepiadaceae) roots have been used in Korean folk medicine for the treatment of diabetes mellitus and aging progression. Also, recent studies have shown that the extract and fractions of Cynanchi Wilfordii Radix have various pharmacological actions including scavenging free radicals, enhancing immunity, reducing high serum cholesterol, and anti-tumor activity. However, the effect of extract of Cynanchi Wilfordii Radix in osteoclast differentiation had not been reported. Thus, we evaluated the effect of Cynanchi Wilfordii Radix on receptor activator of nuclear factor-${\kappa}B$ ligand (RANKL)-induced osteoclast differentiation. Through our study, we found that Cynanchi Wilfordii Radix significantly inhibited osteoclast differentiation induced by RANKL. Cynanchi Wilfordii Radix suppressed the activation of p38 pathway and $NF{\kappa}B$ in bone marrow macrophages (BMMs) treated with RANKL. Also, Cynanchi Wilfordii Radix significantly inhibited the mRNA expression of c-Fos, tartrate-resistant acid phosphatase (TRAP), osteoclast-associated receptor (OSCAR), nuclear factor of activated T cells (NFAT)c1 and cathepsin K in BMMs treated with RANKL. Particularly, Cynanchi Wilfordii Radix inhibited the protein expression of c-fos and NFATc1. Taken together, our results demonstrated that Cynanchi Wilfordii Radix may be useful treatment option of bone-related disease such as osteoporosis leads to fracture of bone and rheumatoid arthritis.

Myogenic Differentiation of p53- and Rb-deficient Immortalized and Transformed Bovine Fibroblasts in Response to MyoD

  • Jin, Xun;Lee, Joong-Seub;Kwak, Sungwook;Jung, Ji-Eun;Kim, Tae-Kyung;Xuo, Chenxiong;Hong, Zhongshan;Li, Zhehu;Kim, Sun-Myoung;Whang, Kwang Youn;Hong, Ki-Chang;You, Seungkwon;Choi, Yun-Jaie;Kim, Hyunggee
    • Molecules and Cells
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    • v.21 no.2
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    • pp.206-212
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    • 2006
  • We have established in culture a spontaneously immortalized bovine embryonic fibroblast (BEF) cell line that has lost p53 and $p16^{INK4a}$ functions. MyoD is a muscle-specific regulator capable of inducing myogenesis in a number of cell types. When the BEF cells were transduced with MyoD they differentiated efficiently to desmin-positive myofibers in the presence of 2% horse serum and 1.7 nM insulin. The myogenic differentiation of this cell line was more rapid and obvious than that of C2C12 cells, as judged by morphological changes and expression of various muscle regulatory factors. To confirm that lack of the p53 and $p16^{INK4a}$ pathway does not prevent MyoD-mediated myogenesis, we established a cell line transformed with SV40LT (BEFV) and introduced MyoD into it. In the presence of 2% horse serum and 1.7 nM insulin, the MyoD-transduced BEFV cells differentiated like the MyoD-transduced BEFS cells, and displayed a similar pattern of expression of muscle regulatory proteins. Taken together, our results indicate that MyoD overexpression overcomes the defect in muscle differentiation associated with immortalization and cell transformation caused by the loss of p53 and Rb functions.

Molecular mechanisms of hederagenin in bone formation (Hederagenin의 뼈 형성 관련 작용 기전 연구)

  • Hyun-Ju Seo;In-Sook Kwun;Jaehee Kwon;Yejin Sim;Young-Eun Cho
    • Journal of Nutrition and Health
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    • v.55 no.6
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    • pp.617-629
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    • 2022
  • Purpose: Osteoporosis is characterized by structural deterioration of the bone tissue because of the loss of osteoblastic activity or the increase in osteoclastic activity, resulting in bone fragility and an increased risk of fractures. Hederagenin (Hed) is a pentacyclic triterpenoid saponin isolated from Dipsaci Radix, the dried root of Dipsacus asper Wall. Dipsaci Radix has been used in Korean herbal medicine to treat bone fractures. In this study, we attempted to demonstrate the potential anti-osteoporotic effect of Hed by examining its effect on osteoblast differentiation in MC3T3-E1 cells. Methods: Osteoblastic MC3T3-E1 cells were cultured in 0, 1, and 10 ㎍/mL Hed for 3 and 7 days. The activity of alkaline phosphatase (ALP), bone nodule formation and level of expression of bone-related genes and proteins were measured in MC3T3-E1 cells exposed to Hed. The western blot test was used to detect the activation of the bone morphogenetic protein-2 (BMP2)/ Suppressor of Mothers against Decapentaplegic (SMAD)1 pathway. Results: Hed significantly increased the proliferation of MC3T3-E1 cells. Intracellular ALP activity was significantly increased in the 1 ㎍/mL Hed-treated group. Hed significantly increased the concentration of calcified nodules. Furthermore, Hed significantly upregulated the expression of genes and proteins associated with osteoblast proliferation and differentiation, such as Runt-related transcription factor 2 (Runx2), ALP, osteopontin (OPN), and type I procollagen (ProCOL1). Induction of osteoblast differentiation by Hed was associated with increased BMP2. In addition, Hed induced osteoblast differentiation by increasing the activity of SMAD1/5/8. These results suggest that Hed has the potential to prevent osteoporosis by promoting osteoblastogenesis in osteoblastic MC3T3-E1 cells via the modulation of the BMP2/SMAD1 pathway. Conclusion: The results presented in this study indicate that Hed isolated from Dipsaci Radix has the potential to be developed as a healthcare food and functional material possessing anti-osteoporosis effects.

Analysis on Strategies for Modeling the Wave Equation with Physics-Informed Neural Networks (물리정보신경망을 이용한 파동방정식 모델링 전략 분석)

  • Sangin Cho;Woochang Choi;Jun Ji;Sukjoon Pyun
    • Geophysics and Geophysical Exploration
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    • v.26 no.3
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    • pp.114-125
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    • 2023
  • The physics-informed neural network (PINN) has been proposed to overcome the limitations of various numerical methods used to solve partial differential equations (PDEs) and the drawbacks of purely data-driven machine learning. The PINN directly applies PDEs to the construction of the loss function, introducing physical constraints to machine learning training. This technique can also be applied to wave equation modeling. However, to solve the wave equation using the PINN, second-order differentiations with respect to input data must be performed during neural network training, and the resulting wavefields contain complex dynamical phenomena, requiring careful strategies. This tutorial elucidates the fundamental concepts of the PINN and discusses considerations for wave equation modeling using the PINN approach. These considerations include spatial coordinate normalization, the selection of activation functions, and strategies for incorporating physics loss. Our experimental results demonstrated that normalizing the spatial coordinates of the training data leads to a more accurate reflection of initial conditions in neural network training for wave equation modeling. Furthermore, the characteristics of various functions were compared to select an appropriate activation function for wavefield prediction using neural networks. These comparisons focused on their differentiation with respect to input data and their convergence properties. Finally, the results of two scenarios for incorporating physics loss into the loss function during neural network training were compared. Through numerical experiments, a curriculum-based learning strategy, applying physics loss after the initial training steps, was more effective than utilizing physics loss from the early training steps. In addition, the effectiveness of the PINN technique was confirmed by comparing these results with those of training without any use of physics loss.

A Study on the Development Methodology of Intelligent Medical Devices Utilizing KANO-QFD Model (지능형 메디컬 기기 개발을 위한 KANO-QFD 모델 제안: AI 기반 탈모관리 기기 중심으로)

  • Kim, Yechan;Choi, Kwangeun;Chung, Doohee
    • Journal of Intelligence and Information Systems
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    • v.28 no.1
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    • pp.217-242
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    • 2022
  • With the launch of Artificial Intelligence(AI)-based intelligent products on the market, innovative changes are taking place not only in business but also in consumers' daily lives. Intelligent products have the potential to realize technology differentiation and increase market competitiveness through advanced functions of artificial intelligence. However, there is no new product development methodology that can sufficiently reflect the characteristics of artificial intelligence for the purpose of developing intelligent products with high market acceptance. This study proposes a KANO-QFD integrated model as a methodology for intelligent product development. As a specific example of the empirical analysis, the types of consumer requirements for hair loss prediction and treatment device were classified, and the relative importance and priority of engineering characteristics were derived to suggest the direction of intelligent medical product development. As a result of a survey of 130 consumers, accurate prediction of future hair loss progress, future hair loss and improved future after treatment realized and viewed on a smartphone, sophisticated design, and treatment using laser and LED combined light energy were realized as attractive quality factors among the KANO categories. As a result of the analysis based on House of Quality of QFD, learning data for hair loss diagnosis and prediction, micro camera resolution for scalp scan, hair loss type classification model, customized personal account management, and hair loss progress diagnosis model were derived. This study is significant in that it presented directions for the development of artificial intelligence-based intelligent medical product that were not previously preceded.

ROLE OF DCC(DELETED IN COLORECTAL CANCER) GENE IN ORAL SQUAMOUS CELL CARCINOMA (구강편평상피암종에서 DCC 유전자의 역할)

  • Ko, Seong-Kyu;Han, Se-Jin;Kim, Kyung-Wook
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.34 no.5
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    • pp.518-524
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    • 2008
  • Chromosome 18q alteration plays a key role in colorectal tumorigenesis, and loss of heterozygosity at 18q is associated with a poor prognosis in colon cancer. DCC(Deleted in Colorectal Cancer) is a putative tumor- suppressor gene at 18q21 that encodes a transmembrane protein with structural similarity to neural cell adhesion molecule that is involved in both epithelial and neuronal cell differentiation. DCC is implicated in regulation of cell growth, survival and proliferation. Thus, tumor progression in squamous cell carcinoma, stomach cancer, colorectal cancer correlates with downregulation of DCC expression. The mechanism for DCC suppression is associated with hypermethylation of the DCC gene promoter region. Hence, the goal of this study is to identify the promoter methylation responsible for the down-regulation of DCC expression in oral squamous cell carcinoma. 12 of tissue specimens for the study are excised and gathered from 12 patients who are diagnosed as SCC in department of OMS, dental hospital, dankook university. To find expression of DCC in each tissue samples, immunohistochemical staining, RT-PCR gene analysis and methylation specific PCR are processed. The results are as follows. 1. In the DCC gene RT-PCR analysis, 5(41.6%) of 12 specimens of oral squamous cell carcinoma did not expressed DCC gene. 2. In the promoter methylation specific PCR analysis, 5(41.6%) of 12 specimens showed promoter methylation of DCC gene. 3. In the immunohistochemical staining of poor differentiated and invasive oral squamous cell carcinoma, loss of DCC expression was observed. These findings suggest that methylation of the DCC gene may play a role in loss of gene expression in invasive oral squamous cell carcinoma.

Suppression of Inflammation, Osteoclastogenesis and Bone Loss by PZRAS Extract

  • Li, Liang;Park, Young-Ran;Shrestha, Saroj Kumar;Cho, Hyoung-Kwon;Soh, Yunjo
    • Journal of Microbiology and Biotechnology
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    • v.30 no.10
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    • pp.1543-1551
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    • 2020
  • Panax ginseng has a wide range of activities including a neuroprotective effect, skin protective effects, enhanced DNA repairing, anti-diabetic activity, and protective effects against vascular inflammation. In the present study, we sought to discover the inhibitory effects of a mixture of natural products containing Panax ginseng, Ziziphus jujube, Rubi fructus, Artemisiae asiaticae and Scutellaria baicalensis (PZRAS) on osteoclastogenesis and bone remodeling, as neither the effects of a mixture containing Panax ginseng extract, nor its molecular mechanism on bone inflammation, have been clarified yet. PZRAS upregulated the levels of catalase (CAT), superoxide dismutase (SOD), glutathione reductase (GSH-R) and glutathione peroxidase (GSH-Px) and reduced malondialdehyde (MDA) in LPS-treated RAW264.7 cells. Moreover, treatment with PZRAS decreased the production of IL-1β and TNF-α. PZRAS also inhibited osteoclast differentiation through inhibiting osteoclastspecific genes like MMP-2, 9, cathepsin K, and TRAP in RANKL-treated RAW264.7 cells. Additionally, PZRAS has inhibitory functions on the RANKL-stimulated activation of ERK and JNK, which lead to a decrease in the expression of NFATc1 and c-Fos. In an in vivo study, bone resorption induced by LPS was recovered by treatment with PZRAS in bone volume per tissue volume (BV/TV) compared to control. Furthermore, the ratio of eroded bone surface of femurs was significantly increased in LPS-treated mice compared to vehicle group, but this ratio was significantly reversed in PZRAS-treated mice. These results suggest that PZRAS could prevent or treat disorders with abnormal bone loss.