RESUMEN
Embryonic stem cells (ESC) need a set of specific factors to be propagated. They can also grow in conditioned medium (CM) derived from a bovine granulosa cell line BGC (BGC-CM), a medium that not only preserves their main features but also increases ESC´s proliferation rate. The mitogenic properties of this medium were previously reported, ascribing this effect to an alternative spliced generated fibronectin isoform that contains the extra domain A (FN EDA(+)). Here, we investigated if the FN EDA(+) isoform increased proliferation of mouse and human ES cells. We analyzed cell proliferation using conditioned media produced by different mouse embryonic fibroblast (MEF) lines genetically engineered to express FN constitutively including or excluding the EDA domain (FN EDA(-)), and in media supplemented with recombinant peptides containing or not the EDA. We found that the presence of EDA in the medium increased mouse and human ESC's proliferation rate. Here we showed for the first time that this FN isoform enhances ESC's proliferation. These findings suggest a possible conserved behavior for regulation of ES cells proliferation by this FN isoform and could contribute to improve their culturing conditions both for research and cell therapy.
Asunto(s)
Células Madre Embrionarias/citología , Células Madre Embrionarias/efectos de los fármacos , Fibronectinas/metabolismo , Animales , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Medios de Cultivo Condicionados/farmacología , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Fibronectinas/genética , Humanos , Ratones , Ratones MutantesRESUMEN
The increasing digitization of information and communication has undoubtedly impacted the ways in which people in the United States access and interpret health information. Although the traditional emphasis of health literacy research has been the comprehension of health-related texts such as patient information forms, prescriptions, and medicine labels, the increased use of electronic means to locate health information requires more critical engagement with texts beyond basic comprehension. In accessing electronic health information, patients need to be able to navigate the vast amount of online health information and to interpret and synthesize health information across multiple sources (i.e. websites) while also evaluating the credibility of these sources. Recent health literacy research has examined the increased role of the media literacy in influencing health behaviors (Bergsma & Carney, 2008) and the role of increased access to computers (Salovey et al., 2009), but little (if any) research to date has provided recommendations for best practices related to meeting the health literacy demands required by digitization. This article attempts to fill this gap by exploring the use of the internet as a key source of health information and by looking at best practices in teaching digital health literacy. It describes the development of a digital literacy component within a community-based health literacy/ESL curriculum funded by the National Institutes of Health and implemented on the US-Mexico border.
RESUMEN
Alternative splicing plays a key role in generating protein diversity. Transfections with minigenes revealed coordination between two distant, alternatively spliced exons in the same gene. Mutations that either inhibit or stimulate inclusion of the upstream alternative exon deeply affect inclusion of the downstream one. However, similar mutations at the downstream alternative exon have little effect on the upstream one. This polar effect is promoter specific and is enhanced by inhibition of transcriptional elongation. Consistently, cells from mutant mice with either constitutive or null inclusion of a fibronectin alternative exon revealed coordination with a second alternative splicing region, located far downstream. Using allele-specific RT-PCR, we demonstrate that this coordination occurs in cis and is also affected by transcriptional elongation rates. Bioinformatics supports the generality of these findings, indicating that 25% of human genes contain multiple alternative splicing regions and identifying several genes with nonrandom distribution of mRNA isoforms at two alternative regions.