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Available from: Christopher Thomas Scott
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    • "It might be possible that derivation research of stem cells in the US was less active because enough cell lines became available in the observation period. However, Scott et al. [10] reported that only 21 cell lines were actually qualified for stem cell research among the 78 cell lines that were approved by NIH during Bush administration. Moreover, only 4 cell lines were actively used for stem cell researches during the period. "
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    ABSTRACT: In this research, we examine how restrictive policy influenced performance in human embryonic stem cell research (hESC) between 1998 and 2008. In previous research, researchers argued whether restrictive policy decreased the performance of stem cell research in some nations, especially in the US. Here, we hypothesize that this policy influenced specific subfields of the hESC research. To investigate the selective policy effects, we categorize hESC research publications into three subfields-derivation, differentiation, and medical application research. Our analysis shows that restrictive policy had different effects on different subfields. In general, the US outperformed in overall hESC research throughout these periods. In the derivation of hESC, however, the US almost lost its competence under restrictive policy. Interestingly, the US scientific community showed prominent resilience in hESC research through international collaboration. We concluded that the US resilience and performance stemmed from the wide breadth of research portfolio of US scientists across the hESC subfields, combined with their strategic efforts to collaborate internationally on derivation research.
    Full-text · Article · Apr 2014 · PLoS ONE
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    • "However, the feasibility of rapid cell selection with scattering patterns has not yet been developed for human stem cells. In this study, one of the most used stem cell lines, H9 (WiCell), was selected as the model line [19]. We demonstrated the feasibility of optical forward-scattering in determining the quality of hESC cell colonies. "
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    ABSTRACT: Background With the prompt developments of regenerative medicine, the potential clinical applications of human embryonic stem cells have attracted intense attention. However, the labor-intensive and complex manual cell selection processes required during embryonic stem cell culturing have seriously limited large-scale production and broad applications. Thus, availability of a label-free, non-invasive platform to replace the current cumbersome manual selection has become a critical need. Results A non-invasive, label-free, and time-efficient optical platform for determining the quality of human embryonic stem cell colonies was developed by analyzing the scattering signals from those stem cell colonies. Additionally, confocal microscopy revealed that the cell colony morphology and surface structures were correlated with the resulting characteristic light scattering patterns. Standard immunostaining assay (Oct-4) was also utilized to validate the quality-determination from this light scattering protocol. The platform developed here can therefore provide identification accuracy of up to 87% for colony determination. Conclusions Our study here demonstrated that light scattering patterns can serve as a feasible alternative approach to replace conventional manual selection for human embryonic stem cell cultures.
    Full-text · Article · Jan 2013 · Biological Procedures Online
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    • "Whereas some have valued publication numbers as evidence for a growing underperformance of the United States in this research field [1, 2], we observed an unaltered high level of contribution of the United States to hESC research over the last decade [3, 4]. In addition, several studies claimed that the Bush administration’s funding policy was causative for the preferential use of only a few hESC lines, namely Wicell’s H1 and H9 lines [5–7], while we have shown that the preferential use of certain hESC lines is independent of a nation’s stem cell policy [4]. Rather, we found that the current global stem cell usage patterns can be effortlessly explained by a cumulative advantage process independent of restrictive or permissive policy influence, and we showed that this model nearly perfectly mirrors factual worldwide stem cell usage patterns [8]. "
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    ABSTRACT: In a recent study published in this journal it was claimed that the rate of publications from US-based authors in the human embryonic stem cell (hESC) research field was slowing or even declining from 2008 to 2010. It was assumed that this is the result of long-term effects of the Bush administration’s funding policy for hESC research and the uncertain policy environment of recent years. In the present study, we analyzed a pool of more than 1,700 original hESC research papers published world-wide from 2007 to 2011. In contrast to the previous study, our results do not support the hypothesis of a decline in the productivity of US-based research but rather confirm a nearly unchanged leading position of US research in the hESC field with respect to both publication numbers and impact of research. Moreover, we analyzed about 500 papers reporting original research involving human induced pluripotent stem cells (hiPSCs) published through 2011 and found a dominant position of US research in this research field as well. Electronic supplementary material The online version of this article (doi:10.1007/s12015-012-9409-0) contains supplementary material, which is available to authorized users.
    Full-text · Article · Oct 2012 · Stem cell reviews
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