Improved genetic manipulation of human embryonic stem cells
Low efficiency of transfection limits the ability to genetically manipulate human embryonic stem cells (hESCs), and differences in cell derivation and culture methods require optimization of transfection protocols. We transiently transferred multiple independent hESC lines with different growth requirements to standardized feeder-free culture, and optimized conditions for clonal growth and efficient gene transfer without loss of pluripotency. Stably transfected lines retained differentiation potential, and most lines displayed normal karyotypes.
The historic takeover of Fannie Mae and Freddie Mac, which could come as soon as this weekend, moved to the forefront of the presidential campaign Saturday.
In the arena that night, the whole last minute was drowned out by cheers — and then when the soaring music swelled, the confetti rained down as the harbinger of balloons and the hopeful first family took the stage, forget about it — it was a perfect end to a convention that last Monday, no one even knew if it would happen. But it did, and I'm so glad to have been there.