• Animal cells and systems
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• v.2 no.1
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• pp.1-8
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• 1998

Hepatocyte growth factor (HGF), originally discovered and cloned as a powerful mitogen for hepatocytes, is a four kringle-containing growth factor which specifically binds to membrane-spanning tyrosine kinase, c-Met/HGF receptor. HGF has mitogenic, motogenic (enhancement of cell movement), morphogenic (e.g., induction of branching tubulogenesis), and anti-apoptotic activities for a wide variety of cells. During embryogenesis, HGF supports organogenesis and morphogenesis of various tissues, including liver, kidney, lung, gut, mammary gland, and tooth. In adult tissues HGF elicits an organotrophic function which supports regeneration of organs such as liver, kidney, lung, and vascular tissues. HGF is also a novel member of neurotrophic factor in nervous systems. Together with the preferential expression of HGF in mesenchymal or stromal cells, and c-Met/HGF receptor In epithelial or endothelial cells, the HGF-Met coupling seems to orchestrate dynamic morphogenic processes through epithelial-mesenchymal (or-stromal) interactions for organogenesis and organ regeneration. HGF or HGF gene may well become unique therapeutic tools for treatment of patients with various organ failure, through its actions to reconstruct organized tissue architectures. This review focuses on recently characterized biological and physiological functions integrated by HGF-Met coupling during organogenesis and organ regeneration.

• Molecules and Cells
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• v.43 no.9
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• pp.774-783
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• 2020

The lung has a vital function in gas exchange between the blood and the external atmosphere. It also has a critical role in the immune defense against external pathogens and environmental factors. While the lung is classified as a relatively quiescent organ with little homeostatic turnover, it shows robust regenerative capacity in response to injury, mediated by the resident stem/progenitor cells. During regeneration, regionally distinct epithelial cell populations with specific functions are generated from several different types of stem/progenitor cells localized within four histologically distinguished regions: trachea, bronchi, bronchioles, and alveoli. WNT signaling is one of the key signaling pathways involved in regulating many types of stem/progenitor cells in various organs. In addition to its developmental role in the embryonic and fetal lung, WNT signaling is critical for lung homeostasis and regeneration. In this minireview, we summarize and discuss recent advances in the understanding of the role of WNT signaling in lung regeneration with an emphasis on stem/progenitor cells.

• Plant Resources
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• v.8 no.3
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• pp.286-292
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• 2005

Shoot induction system was developed in the recalcitrant plant species, Brassica rapa ssp. rapifera by using optimum selection of profit organ, phytohormone combination, seedling age and kind of culture container. Out of in vitro cultured leaf segment, petiole, hypocotyl, and cotyledon with petiole, only cotyledon with petiole derived from 4 day-old seedlings induced multiple shoot. The optimum combination of auxin and cytokinin for the multiple shoot induction was MS medium containing 5mg/L BA and 0.5mg/L NAA. The major factors for multiple shoot propagation were part of plant organ, age of seedling, and ratio of auxin and cytokinin. In addition, shoot regeneration was promoted in the 100ml Erlenmeyer flask compared with the $90mm{\times}20mm$ Petri-dish. The induced shoots formed roots easy on MS medium containing 0.1mg/L IBA and the whole plants were successfully cultivated in soil.

• Biomedical Science Letters
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• v.9 no.1
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• pp.1-8
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• 2003

Liver is an organ having an ability to regenerate by itself when it is damaged or removed. Since the research on the liver regeneration so far was regarding on the cellular multiplications not the formation of the shape, we intended to analyze the expression pattern of Hox genes during liver regeneration. RNA samples isolated from liver at the time of partial hepatectomy, 4 hours as well as 3 days later following regeneration were used to perform RT-PCR with Hox-specific degenerate primers. The PCR products were cloned, sequenced and analyzed through BLAST program. Genes belonging to the AbdB type Hox genes (paralogous groups IX-XIII) expressed predominantly during regeneration, while the other group (I-VII), especially Hoxal and bl seemed to be expressed continuously before and after regeneration. These data altogether imply that paralogous group IX and X genes including Hoxa10 and d10 seemed to be regeneration specific genes of liver.

• Journal of Plant Biotechnology
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• v.30 no.1
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• pp.41-45
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• 2003

A study was under taken to investigate the appropriate explant sources of flower organ and suitable cultural conditions such as light, temperature, and sucrose in plant regeneration of Iris ensata culture. Explants of perianth, ovary, pedicel, and peduncle of Iris ensata were cultured at different daylength (0, 8, 16, 24 hour), different temperatures (10, 15, 25, 3$0^{\circ}C$), and sucrose concentrations (1, 3, 6, 9%) on MS medium. Formation of adventitious roots from explants of Iris ensata was effective in the dark, while that of adventitous shoots was effective in the light. The optimum daylength for young plant regeneration was 16 hours. The optimum temperature for shoot formation of Iris ensata explants was $25^{\circ}C$ but the formation at 10 and 15$^{\circ}C$ was ineffective. Especi-ally, perianth and ovary was effective in shoot formation from flower organ expants. T-he optimum concentration of sucrose for shoots and roots formation of Iris ensata explants was 3 and 6%, respectively.

• Macromolecular Research
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• v.13 no.4
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• pp.277-284
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• 2005

The loss or failure of an organ or tissue can occur because of accident or disease, for which tissue or organ transplantation is a generally accepted treatment. However, this approach is extremely limited due to donor shortage. Tissue engineering is a new and exciting strategy, in which patients who need a new organ or tissue are supplied with a synthetic organ or tissue. In this approach, tissues are engineered using a combination of the patient's own cells and a polymer scaffold. The polymer scaffold potentially mimics many roles of extracellular matrices in the body. Various polymers have been studied and utilized to date in tissue engineering approaches. However, no single polymer has been considered ideal for all types of tissues and approaches. This paper discusses the design parameters of those polymers potentially useful in tissue regeneration.

• BMB Reports
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• v.51 no.3
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• pp.106-118
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• 2018

How the organ size is adjusted to the proper size during development and how organs know that they reach the original size during regeneration remain long-standing questions. Based on studies using multiple model organisms and approaches for over 20 years, a consensus has been established that the Hippo pathway plays crucial roles in controlling organ size and maintaining tissue homeostasis. Given the significance of these processes, the dysregulation of the Hippo pathway has also implicated various diseases, such as tissue degeneration and cancer. By regulating the downstream transcriptional coactivators YAP and TAZ, the Hippo pathway coordinates cell proliferation and apoptosis in response to a variety of signals including cell contact inhibition, polarity, mechanical sensation and soluble factors. Since the core components and their functions of the Hippo pathway are evolutionarily conserved, this pathway serves as a global regulator of organ size control. Therefore, further investigation of the regulatory mechanisms will provide physiological insights to better understand tissue homeostasis. In this review, the historical developments and current understandings of the regulatory mechanism of Hippo signaling pathway are discussed.

• Molecules and Cells
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• v.46 no.10
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• pp.573-578
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• 2023

The mammalian skin contains hair follicles, which are epidermal appendages that undergo periodic cycles and exhibit mini-organ features, such as discrete stem cell compartments and different cellular components. Wound-induced hair follicle neogenesis (WIHN) is the remarkable ability to regenerate hair follicles after large-scale wounding and occurs in several adult mammals. WIHN is comparable to embryonic hair follicle development in its processes. Researchers are beginning to identify the stem cells that, in response to wounding, develop into neogenic hair follicles, as well as to understand the functions of immune cells, mesenchymal cells, and several signaling pathways that are essential for this process. WIHN represents a promising therapeutic approach to the reprogramming of cellular states for promoting hair follicle regeneration and preventing scar formation. In the scope of this review, we investigate the contribution of several cell types and molecular mechanisms to WIHN.

• Proceedings of the KIEE Conference
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• 2008.10b
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• pp.484-485
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• 2008

초음파는 의학적 진단 및 치료의 목적으로 널리 사용되어 왔다. 일반적으로, 초음파 조사의 생물학적 무해성은 많은 연구를 통하여 보고되었으나, 최근 초음파 집속을 통한 강력 초음파의 사용에 대한 열적 안전성 평가가 중요한 요소로 대두되고 있다. 이에 본 연구에서는 강력 집속 초음파의 전달 에너지와 열적 분포를 측정하여 안전성 평가에 활용 가능한 초음파 열분포 팬텀을 제안하였다. 온도 분포 측정용 팬텀은 초음파 조직유사 팬텀 재료인 한천을 이용하였으며, 음향학적 특성의 유사성을 평가하였다. 온도 효과를 측정하기 위하여 $3{\times}3$의 형태로 온도 센서를 팬텀 내부에 배열하여 초음파 조사에 따른 온도 분포를 측정하였고 온도 측정을 위한 시스템을 개발하여, 초음파 가열 실험을 수행하였다. 본 연구에서 제안된 초음파 온도 분포 측정용 팬텀의 유용성을 확인하였으며, 온도 분포용 팬텀을 통한 강력 집속 초음파 장비의 열적 성능 평가에 적용 될 수 있을 것으로 사료되었다.

• Journal of Sensor Science and Technology
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• v.17 no.3
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• pp.210-216
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• 2008

The propose of this study is evaluating which correlation of foot pressure distribution and scoliosis that happen by walking to 20'th Mens that have not experienced a scoliosis. The propose of this study is evaluating which correlation of foot pressure distribution and scoliosis that happen by walking to 20'th Mens that have not experienced a scoliosis. Measurement and analysis of Foot Pressure was executed by using by F-scan System. Degree of scoliosis was expressed as a angle used x-ray image of 5-lumbar from 4-thoracic vertebra The correlation between result of foot pressure and degree of scoliosis was evaluated under 0.05 interrelationship, and variables used for analysis were showed high correlation.