Mapping Science - Mapping Scientific Frontiers: The Quest for Knowledge Visualization - page 271

Regenerative medicine is a rapidly growing and fast-moving interdisciplinary
field of study, involving stem cell research, tissue engineering, biomaterials, would
healing, and patient-specific drug discovery (Glotzbach et al. 2011 ;Polak 2010 ;
Polykandriotis et al. 2010 ). The potential of reprogramming patients' own cells
for biological therapy, tissue repairing and regeneration is critical to regenerative
medicine. It has been widely expected that regenerative medicine will revolutionize
medicine and clinical practices far beyond what is currently possible. Mesenchymal
Stem Cells (MSCs), for example, may differentiate into bone cells, fat cells, and
cartilage cells. Skin cells can be reprogrammed into induced pluripotent stem cells
(iPSCs). The rapid advance of the research has also challenged many previous
assumptions and expectations. Although iPSCs resemble embryonic stem cells in
many ways, comparative studies have found potentially profound differences (Chin
et al. 2009 ;Fengetal. 2010 ; Stadtfeld et al. 2010 ).
The body of the relevant literature grows rapidly. The Web of Science has 4,295
records between 2000 and 2011 based on a topic search of the term “regenerative
medicine” in titles, abstracts, or indexing terms. If we include records that are
relevant to regenerative medicine, but do not use the term “regenerative medicine”
explicitly, the number could be as ten times higher. Stem cell research plays a
substantial role in regenerative medicine. There are over two million publications on
stem cells on Google Scholar. There are 167,353 publications specifically indexed
as related to stem cell research in the Web of Science. Keeping abreast the fast-
moving body of literature is critical not only because new discoveries emerge from
a diverse range of areas but also because new findings may fundamentally alter the
collective knowledge as a whole (Chen 2012 ).
In fact, a recent citation network analysis (Shibata et al. 2011 ) identified future
core articles on regenerative medicine based on their positions in a citation networks
derived from 17,824 articles published before the end of 2008. In this review, we
demonstrate a scientometric approach and use CiteSpace to delineate the structure
and dynamics of the regenerative medicine research. CiteSpace is specifically
designed to facilitate the detection of emerging trends and abrupt changes in
scientific literature. Our study is unique in several ways. First, our dataset contains
relevant articles published between 2000 and 2011. We expect that it will reveal
more recent trends emerged within the last 3 years. Second, we use a citation index-
based expansion to construct our dataset, which is more robust than defining a
rapidly growing field with a list of pre-defined keywords. Third, emerging trends
are identified based on indicators computed by CiteSpace without domain experts'
intervention or prior working knowledge of the topic. This approach makes the
analysis repeatable with new data and verifiable by different analysts.
CiteSpace is used to generate and analyze networks of co-cited references based
on bibliographic records retrieved from the Web of Science. An initial topic search
for “regenerative medicine” resulted in 4,295 records published between 2000 and
2011. After filtering out less representative record types such as proceedings papers
and notes, the dataset was reduced to 3,875 original research articles and review
articles.