Regenerative medicine of the Liver: Beyond bench to clinic : Recent Advances and Current Trend in Tissue Engineering

( James J. Yoo ) 대한간학회 2014 춘·추계 학술대회 (KASL) Vol.2014 No.2

Recent advances in tissue engineering and regenerative medicine have provided new therapeutic opportunities for repairing tissue abnormalities. We have followed an engineering strategy that involves the use of biocompatible matrices, either with or without cells. Matrices are either used as a cell delivery vehicle or as scaffolds to promote and enhance tissue regeneration. When cells are used, target cells obtained from donor tissue are expanded in culture, attached to a support matrix, and re-implanted into recipient for recovery of tissue function. While this classical tissue engineering approach using cells and scaffolds has shown to be successful in building new tissues, only a limited number of tissue applications have been translated clinically. It is evident that challenges still exist in developing complex and composite tissue systems that require coordinated and systemic function. In this session, strategies that address these challenges will be discussed.

The varying impact of land subsidence and earth fissures on residential property values in Maricopa County – a quantile regression approach

James Yoo,Thomas Frederick 서울시립대학교 도시과학연구원 2017 도시과학국제저널 Vol.21 No.3

This paper uses quantile regression to examine the impact of land subsidence and earth fissures on residential property values across different quantiles of distribution in housing prices in Maricopa County, Arizona. Using 82,716 arms-length property sales between 2004 and 2010, we estimated a fixed effects quantile regression model predicting the impact of land subsidence and earth fissures on property values. We found that both land subsidence and earth fissures had a negative impact on property values. The impact of land subsidence and earth fissures vary statistically across different distributions of housing prices. Disamenity impacts are found to be more pronounced at high-priced homes while they are statistically insignificant at substantially lower priced homes.

Applications of Organoids for Tissue Engineering and Regenerative Medicine

Yoo James J.,조종수,조인호 한국조직공학과 재생의학회 2020 조직공학과 재생의학 Vol.17 No.6

Open space premium near commercial zones – a case study in the City of Corona, California

James Yoo,Julianna Browning,Kenneth Minesinger 서울시립대학교 도시과학연구원 2018 도시과학국제저널 Vol.22 No.3

The study estimates the economic impact of urban open space on residential properties in the city of Corona, California. Using 4243 non-arms-length transactions and a spatial error model (SEM) hedonic model, we estimate the mean marginal willingness-to-pay (MWTP) for increasing the area of urban open space by 10% within 100 m buffer of residential properties. The results show that urban open space adds value to homes. In addition, we discover that the impacts of open space vary with the distance to the nearest commercial areas. The mean MWTP for open space appears to increase when properties are located closer to commercial zones.

Application of Image Analysis for Precise, Noninvasive Measurement of Plant Culture Growth

James, Eddie,Yoo, In Sang,Lee, James M. 한국화학공학회 2004 Korean Journal of Chemical Engineering Vol.21 No.1

Accurately measuring the growth of solid cultures is important for evaluating regrowth following low temperature storage, cell screening on selective media, or the suitability of different media formulation. However, current procedures are inadequate to provide precise, quantitative data non-invasively. This paper describes the development of an image analysis technique to provide quantitative growth data for callus cultures. Various properties obtained from image analysis, such as area, perimeter, diameter, and integrated density valued, were correlated with the observed mass of plant callus. Based on this data, a predictive linear model was developed. The image analysis method was used to estimate cell mass as a function of various media components and growth conditions. This work demonstrates that image analysis is a flexible and useful tool for monitoring cultures.

Regenerative Medicine Strategies for Treating Neurogenic Bladder

James J. Yoo,Jennifer Olson,Anthony Atala,김법완 대한배뇨장애요실금학회 2011 International Neurourology Journal Vol.15 No.3

Neurogenic bladder is a general term encompassing various neurologic dysfunctions of the bladder and the external urethral sphincter. These can be caused by damage or disease. Therapeutic management options can be conservative, minimally invasive, or surgical. The current standard for surgical management is bladder augmentation using intestinal segments. However, because intestinal tissue possesses different functional characteristics than bladder tissue, numerous complications can ensue, including excess mucus production, urinary stone formation, and malignancy. As a result, investigators have sought after alternative solutions. Tissue engineering is a scientific field that uses combinations of cells and biomaterials to encourage regeneration of new, healthy tissue and offers an alternative approach for the replacement of lost or deficient organs, including the bladder. Promising results using tissue-engineered bladder have already been obtained in children with neurogenic bladder caused by myelomeningocele. Human clinical trials, governed by the Food and Drug Administration, are ongoing in the United States in both children and adults to further evaluate the safety and efficacy of this technology. This review will introduce the principles of tissue engineering and discuss how it can be used to treat refractory cases of neurogenic bladder.

Application of Image Analysis for Precise, Noninvasive Measurement of Plant Culture Growth

James M. Lee,Eddie James,In Sang Yoo 한국화학공학회 2004 Korean Journal of Chemical Engineering Vol.21 No.1

Accurately measuring the growth of solid cultures is important for evaluating regrowth folowing low tem-perature storage, cel screening on selective media, or the suitability of diferent media formulations. However, currentprocedures are inadequate to provide precise, quantitative data non-invasively. This paper describes the developmentof an image analysis technique to provide quantitative growth data for callus cultures. Various properties obtained fromimage analysis, such as area, perimeter, diameter, and integrated density value, were corelated with the observed massof plant calus. Based on this data, a predictive linear model was developed. The image analysis method was used toestimate cel mass as a function of various media components and growth conditions. This work demonstrates thatimage analysis is a flexible and useful tool for monitoring cultures.

Application of variable threshold intensity to segmentation for white matter hyperintensities in fluid attenuated inversion recovery magnetic resonance images

Yoo, Byung Il,Lee, Jung Jae,Han, Ji Won,Oh, San Yeo Wool,Lee, Eun Young,MacFall, James R.,Payne, Martha E.,Kim, Tae Hui,Kim, Jae Hyoung,Kim, Ki Woong Springer-Verlag 2014 Neuroradiology Vol.56 No.4

Operation of Community Resident Groups in a Community-Based Participatory Health Promotion Program for Low-income Older Adults

Yoo, Seung-Hyun,Butler, James,Elias, Thistle I. Korean Society for Health Education and Promotion 2009 보건교육건강증진학회지 Vol.26 No.5

목적: 지역사회 참여형 보건 연구에서 현장의 지식과 경험을 토대로 주요 보건문제를 파악하고 대응하기에 중요한 역할을 하는 지역사회 주민 조직의 구성과 운영상의 특성을 논의하고자 한다. 방법: 미국 펜실베이니아 주 12개 저소득층 정부임대 아파트의 노인 입주자들을 대상으로 각 아파트마다 자발적인 주민조직을 구성하여 사회생태학 모형을 활용한 6단계 지역사회 역량강화 과정을 수행하였다. 주민조직의 과정과 성과를 기록한 200여건의 문건에 대해 질적 연구 분석을 실시하였다. 결과: 2년간 주민조직 월례회의를 통하여 낙후된 아파트 건물상태, 신선한 식재료 마련, 주민 간 관계개선 등을 지역사회 건강증진의 우선순위로 선정하고, 자체적인 해결방안을 구상하여 추진하였다. 주민조직 내의 리더십, 주민조직에 꾸준히 참여하는 핵심 회원, 주민조직 회의 개최의 일관성이 주민들에 의한 자치적인 지역사회 건강증진 활동의 주요 특성으로 드러났다. 리더십이 형성되고 회원의 참여와 회의의 개최가 꾸준한 주민조직일수록 지역사회 건강증진 목표 및 관련활동이 집중적인 경향이 있었다. 결론: 리더십, 참여, 일관성 등은 참여적이고 자치적인 지역사회 건강증진을 위한 역량요인이며, 이러한 역량을 개발하고 강화하는 과정에 대한 모니터링과 과정평가의 중요성이 강조된다. Objectives: This paper is intended to illustrate and to discuss the organization and functioning of community resident groups (CRGs) in a community-based participatory health promotion program for healthy aging. Methods: CRGs were convened in 12 government-subsidized apartment communities for low-income seniors in Pennsylvania, U.S.A., to promote healthy aging. Researchers facilitated CRG meetings following a 6-step process of community empowerment and utilizing a social ecological model for assessment and planning. Almost 200 project-related documents were qualitatively analyzed using matrix analysis principles such as cross-classification of multiple dimensions to identify patterns in the data and matrix building for displaying such patterns. Results: CRGs were venues at which apartment building residents could interact, discuss health priorities, and become change agents in their building. CRG members' community health priorities were about their daily living, including building conditions, poor access to fresh food, and unhealthy resident relations. Specific patterns arose in analysis indicating that leadership withing the CRGs, consistency of meetings and participants' attendance, and ability to link health concerns to daily experience impacted the CRGs' capability to identify and accomplish their goals. Conclusion: Community health issues and solutions to those issues identified by CRGs were unique to community contexts and interests. Consistent participation by community members, a consistent pattern of group activities such as monthly meetings, and having established leadership to manage CRG activities were prominent characteristics of community group functioning.

Real-time Monitoring of Packet Processing Time for Virtual Network Functions

James Won-Ki Hong,Jae-Hyoung Yoo,Nguyen Van Tu 한국통신학회 2020 한국통신학회 APNOMS Vol.2020 No.09

By enabling the deployment of softwarelized network functions on commodity servers, Network Function Virtualization (NFV) brings many benefits such as rapid development and deployment, simplicity and flexibility in network operations and management. Monitoring the performance characteristics of Virtual Network Functions (VNFs), such as packet processing time, is crucial to achieving maximum benefit from NFV. In this paper, we present Packer Processing Time Monitoring (PPTMon) - a solution for real-time and lightweight VNF packet processing time monitoring. PPTMon embeds timestamp information directly into the packets. PPTMon is implemented using extended Berkeley Packet Filter (eBPF) - a new Linux framework that allows high-speed packet processing. Our experiments showed that PPTMon can monitor VNFs with high accuracy and low performance overhead.