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Cancer is a disease caused by a group of cells that multiply uncontrollably and autonomously, invading other tissues locally and distance to others. Cancer stem cells are of great interest, since they are attributed the ability to originate, maintain and expand tumors, as well as to cause metastasis and tumor reappearance. The objective is to obtain cancer stem cells from the triple negative breast cancer cell line. The 4 subpopulations of the CD44 + / cd24- immunophenotype were obtained. Conclusions: Breast cancer stem cells (BCSC) have been the subject of concentrated research as potential targets for breast cancer therapies. CD44+/CD24- cell surface markers have been established as minimal biomarkers for stem cell of breast cancer BCSC. [ABSTRACT FROM AUTHOR]

Growing cells in plastic with liquid media for in vitro study is very common but far from physiological. The use of scaffold materials is more biocompatible. Extracellular matrix provides tissue integrity which acts as a native scaffold for cell attachment and interaction, as well as it serves as a reservoir for growth factors. For this reason, we have developed natural scaffold from mice fibroblast to form a natural scaffold for stem cell culture. Fibroblasts were cultured under crowded condition and lysed to form natural scaffold. The natural scaffold formation was observed using immunofluorescence which then will be used and tested for stem cell propagation and differentiation. [ABSTRACT FROM AUTHOR]

In this study, we developed a method to induce pluripotency of adult cells (fibroblast) into stem cells using a natural product, extract of fish oocyte, by comparing the extract concentration, 1 mg/ml and 2 mg/ml. The analyses were done by measuring the Nanog gene expression in cells using qPCR and detecting fibroblast marker anti H2-KK. The results revealed existence of a colony of stem cells in the cell that was induced with 2mg/ml concentration of oocytes. Nanoggene expression was analyzed by qPCR and the results showed expression of Nanog gene compared to the control. Analysis of result of fibroblast using Tali Cytometer and anti H2KK antibody showed loss of expression of Anti H2KK meaning there was transformation from fibroblast type cell to pluripotent cell type. [ABSTRACT FROM AUTHOR]

Embryonic stem cells are undifferentiated cells that are able to differentiate into all derivatives of the three germ layers called as ectoderm, endoderm and mesoderm. They can develop into the more than 200 cell types of the adult body. Tracking the proliferation of embryonic stem cells is a tedious task which often is undertaken manually. So, for this purpose automatic counting methods are strongly desirable. In this study, we propose automatic embryonic stem cell detection and a counting method. Stem cell sections were obtained under the fluorescence microscopy. In the pre-processing stage color image is split into channels. Then a Gaussian filter is applied to green channel of the cell image to eliminate the noise and highlight the maximum points of the cell. Furthermore background segmentation is applied by thresholding. Histogram partitioning is performed to detect the connected component of the pre-processed cell image. Finally maximum point analysis is investigated to count the cells automatically. The effectiveness of the proposed method is evaluated by using Matlab. It is shown that the proposed method gives promising results and can eliminate the subjectivity originated from the manual counting. The method is tested on a database of 92 images that were validated by the specialists. [ABSTRACT FROM AUTHOR]

Neural stem cells and neural progenitors are early nervous system cells that form neurospheres when propagated in vitro. We study changes in growth using brightfield images to understand the effects of drugs. The image quality is generally poor, imposing challenges for automatic analysis. Level-set segmentation methods are able to handle topology changes but require close initializations for accurate and efficient results. Global level-set methods using single image-wide optimization objective functions are difficult to cope with large illumination and shading changes. We propose to adopt Hough transform to initialize localized level-sets for cell segmentation. Experimental results on 480 images with 738 neurospheres show that our proposed method performs best over existing level-set methods without appropriate initial contours. [ABSTRACT FROM PUBLISHER]

We present a texton-based, multi-stage Bayesian level set algorithm which we use to segment colony images of hESC and their derivatives. We extend our previous research segmenting stem cells according to multiresolution texture methods to accommodate colonies and tissues with diffuse and varied textures via a filter bank approach similar to the MR8. Texture features computed for test images are classified via comparison with learned sets of class-specific textural primitives, known as textons. Encompassing this texture model is the new Bayesian level set algorithm, which smoothes and regularizes classification similar to level sets but is simpler in its probabilistic implementation. The resulting algorithm accurately and automatically classifies images of pluripotent hESC and trophectoderm colonies for high-content screening applications. [ABSTRACT FROM PUBLISHER]

This article proposes new theoretical perspective to the dynamics of scientific politics and its representation. In critical review of Latour and Bourdieu's theory, the proposition of the Ontological Network and relevant network analysis attempts at providing better understanding of the actual scientific case: the infamous Korean stem cell scandal(the scientific misconduct of Hwang Woo Suk) in 2006.For the case study, it analyzes the transformation of the scientific network of stem cell researchers in Korea: 2004-2005. During the short period, there was rapid change in the relation of stem cell researchers and the power distribution. Through the mutual interaction of the actor and the structure, it elucidates the actor's strategy to secure recognition and the structural constraints.Hwang Woo Suk was initially positioned in a relatively alienated place in the actor's network. The isolation represented the institutional practice of hierarchy and the cultural practice of nepotism in Korean society. To overcome the isolation and acquire recognition, he applied the same practice in the network. The effect of the same practices he utilized, however, also worked against forming a stable alliance in the domestic field, pressuring him for the quick, often exaggerated, or even fabricated, results.Acknowledging that the conclusion on the causality is a reflection of the researcher's own perspective, in its epistemological sense, the systemic comparison with the different public perception was made. By this comparison, this study tries to reveal the underlying perception of the public on the scientific event- Hwang's scandal, and the meaning of the representation. ..PAT.-Unpublished Manuscript [ABSTRACT FROM AUTHOR]

The article examines the relationship between source credibility and news coverage of organizations involved in the stem cell and/or cloning debate. The article also involves a content analysis of 883 news stories to rate how the news content portrayed those 30 organizations in terms of five indicators of news coverage. The findings suggest that source credibility is related to the quality aspect of news coverage, such as regular and positive coverage, whereas it is not related to the amount of news coverage.

The article examines how media access of a given source reflects two sets of influences such as its legitimacy standing in the scale of journalists' perceptions and its public relations expertise. There is a tendency among journalists to evaluate some sources as more legitimate than others. This leads them to treat the more legitimate sources favorably by granting them more media access. Therefore, journalists play a role in influencing the extent of sources' media access.

Emerging nanofiber technology offering a new tool to study biological questions that otherwise cannot be appropriately addressed by current technologies has been widely used for various biomedical applications. Particularly, in the last decade, the potential of nanofibers produced by electrospinning has been extensively explored for regenerative medicine, including tissue engineering, cell therapy, and drug delivery. Growing interest of using nanofibers for regenerative medicine applications has been indicated by an increasing number of scientific publications focusing on nanofibers for tissue engineering scaffolds or drug carriers. Nanofibers are ultra-fine fibers with the diameter and morphology resembling natural extracellular matrix (ECM), which makes them suitable as a three-dimensional ECM substitute for tissue generation. The biomimetic properties have been demonstrated to be a key trait that is capable of inducing favorable biological response of various cell types, including stem cells. In addition, composed of nanometer-sized fibers, a nanofibrous matrix is a highly porous structure with a high surface area-to-volume ratio for accommodation of a large quantity of cells. These unique properties suggest that nanofibers can function as synthetic ECM to culture stem cells for tissue generation. To date, many synthetic or natural polymers have been electrospun and characterized for different tissue engineering applications, including cartilage, nerve, and skin, and the results are generally promising. My research has been focused on investigating the potential of nanofibers for generation of musculoskeletal tissues, such as bone, cartilage, and tendon. We have reported that stem cells cultured in nanofibers establish biologically favorable cell-matrix interaction with surrounding nanofibers, which instructs cells to enhance lineage-specific differentiation, maintain cell phenotype, and/or produce tissue-specific ECM. We have also demonstrated that nanofibers are able to recapitulate a stem cell microenvironment and thereby direct cell response through the cues of nano-features to prevent cell senescence and enhance the multi-differentiation capacity. Taken together, nanofibers as artificial ECM for stem cell-based tissue generation is promising and the interest of using nanofibers for regenerative medicine applications is expected to continually grow. [ABSTRACT FROM AUTHOR]

Within the context of the 2004 presidential election, this study explores the relationships between discussion networks and the development of extreme attitudes toward stem cell research. We offer a structural model that addresses a discrepancy in previous attitude formation research - whether interpersonal discussion leads to attitude extremity, or extremity leads to discussion. By using data based on a longitudinal, nationwide mail survey carried out between 2002 and 2005, we explore within-wave and between-wave causal paths, revealing patterns difficult to discern in traditional attitude formation experimental designs. Our findings show that it is discussion itself - and not media - that directly influences the formation of extreme attitudes. Furthermore, the type of discussion plays a substantial role in shaping these attitudes, with networks composed of likeminded others leading directly to the development of extreme attitudes toward stem cell research. ..PAT.-Unpublished Manuscript [ABSTRACT FROM AUTHOR]