DAVID GRANOVSKY

Posts Tagged ‘letterman’

Sperm Stem Cell Expiration Date?

In ALL ARTICLES on August 26, 2009 at 2:04 pm

Do men have a best-before date when it comes to fathering kids? Ridiculous, most of us would answer. Just look at these celebrity old guys who became dads in their 50s, 60s, and beyond: Charlie Chaplin at 73; former prime minister Pierre Trudeau at 72, Pablo Picasso at 68; Larry King at 65; Warren Beatty at 63; and Dave Letterman at 56.

https://i2.wp.com/4.bp.blogspot.com/_3y3MF-4HXAM/SFowRAG3FfI/AAAAAAAAEN8/ABlsqfpkE94/s400/picasso-sylvette.jpg

“Women are born with a fixed number of oocytes,” says Dr. Bernard Robaire, describing the female germ cells crucial to reproduction. The McGill University researcher who is funded by the Canadian Institutes of Health Research (CIHR), says that men have no such limitation. Unlike women who, after the age of 35 find it more difficult to get pregnant, men produce 1,000 sperm a heartbeat–about 100 million sperm each day.

Theoretically speaking, then, men can go forth and multiply forever — or as long as their hearts beat. “The argument has always been that because men keep producing sperm that are fresh all the time it makes no difference whether you have sperm from an 85-year-old man or a 35-year-old man,” says Robaire.

However, there’s a growing body of research that suggests there may be limits to men’s fertility, too. Recent studies have shown that men over the age of 40 have a lower chance of producing children than their younger counterparts. And they have an elevated risk of having children with autism, bipolar disease and schizophrenia.

In addition to concerns about mental illness, some studies have also shown that children born to older fathers score lower on intelligence tests. One study found that the incidence of down syndrome was related to sperm approximately 50% of the time.

“What we found was that if you put old males with young females, the development of the says Robaire, explaining his work with lab only the quality of the sperm,” he stresses. So is there a biological clock for men? “Yes, because a biological clock doesn’t just refer to the number of sperm produced but also their quality.” Robaire adds that there are many older men who produce children who are normal in every way. Nonetheless, studies show that the best age for perfect sperm is under 40.

via Best before… – Northern News – Ontario, CA.

STEM CELL NEWS: “more federal support for embryonic stem cell research”

In ALL ARTICLES, STEM CELLS IN THE NEWS on February 10, 2009 at 1:59 am


Harvard’s Holdren Wields Oscar-Worthy Climate Pitch for Obama

By John Lauerman

(info relevant to stem cell issues are in bold)

Feb. 10 (Bloomberg) — When David Letterman, the late-night TV host, needed a scientist to explain climate change on his show last April, he chose John Holdren, the Harvard University physicist who helped Al Gore earn an Academy Award…

As the head of the technology office, Holdren would also be co-chair of the President’s Council of Advisors on Science and Technology, along with Harvard geneticist Eric Lander and Harold Varmus, the Nobel Prize-winning virologist who is president of the Memorial Sloan-Kettering Cancer Center in New York. All three declined to be interviewed until after Holdren’s confirmation.

Leonard Zon, a Harvard stem cell scientist who knows Lander and Varmus and has followed Holdren’s career, said the three men are likely to recommend more federal support for embryonic stem cell research, and budget increases for the National Institutes of Health, the U.S. agency that backs the bulk of basic science conducted at academic institutions.

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via http://www.bloomberg.com/apps/news?pid=20601103&sid=aT9Qr0JjWycs&refer=us

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