Scientists who report their findings are expected to discuss the problems as well as the outcome of their research. The "Discussion" is the best place to figure out what a report means (And then you go back and check to see if they proved what they "discussed." And then, you wait for other labs to confirm it.)
The actual (Takahashi et al., Induction of Pluripotent Stem Cells from Adult Human Fibroblasts by Defined Factors, Cell (2007).) Cell article on reprogrammed adult fibroblasts from skin cells, the "induced Pluripotent Stem Cells) or "iPS," is available free, here. The abstract of the Science Magazine report on similar work by Thomson from Wisconsin (the guy who first reported human embryonic stem cells, in the first place) is free, here, although the actual article is for subscribers only.
To the best of my understanding, here's what I think the Takahashi/Yamaka report means:
While it took a lot of cells and a lot of time,
1. the cells that grew looked like human embryonic stem cells with a few minor differences,
2. they believe they proved their technique is responsible for all the new pluripotent cells (there weren't any cells from another culture introduced accidentally or on purpose, to give them better results),
3. the cells could be directed to develop nerve cells and heart cells,
4. that they were able to use other types of adult cells to achieve iPS, and
5. the researchers suggest several possible ways to overcome the drawbacks of the process.
This is an excerpt from LifeEthics. There's several more posts on these two articles, with links. Be sure and read, " Insult in Science Magazine on "Race" to Stem Cell Breakthrough," (so you can stop worrying).
