Guest: Dr. John Jurist. Topics: This is the first in a series of programs focused on the use of bisphosphonates to mitigate bone loss in long duration spaceflight. You are invited to comment, ask questions, & discuss the Space Show program/guest(s) on the Space Show blog, http://thespaceshow.wordpress.com. Comments, questions, & any discussion must be relevant & applicable to Space Show programming. Transcripts of Space Show programs are not permitted without prior written consent from The Space Show (even if for personal use) & are a violation of the Space Show copyright. We welcomed back Dr. John Jurist for the first of several programs devoted to understanding bone loss in microgravity & the use of prescription the bisphosphonate family of drugs to mitigate the problem. Dr. Jurist provided talking points which you can find below this summary on The Space Show blog. A significant portion of the second segment is devoted to understanding these talking points so follow along. We started our discussion with an explanation of the bone loss problem facing those in microgravity. Following this brief overview, Dr. Jurist told us about bisphosphonates, the origins of this drug, how it was developed, how its usage, what some of the side effects are, some of the trials that have been associated with the drug, & space/NASA studies. Later in this nearly hour long segment, we talked about the human population & what happens to our bone mass at various stages in our life. We talked about gender, racial, & ethnic differences in human bone mass issues. As you will hear, there are gender & other differences among our diverse population. This led us to asking about using targeted genetics in selecting crews for longer spaceflight missions. Genetic modification was mentioned, especially for the long term, but for the near term, looking for better exercise routines & pharmaceutical modification/treatment seem to hold the most promise. Dr. Jurist then talked about bisphosphonate side effects. Fast transit time to Mars or a long duration mission destination came up. As you will hear, even if you get to Mars faster, you still have the problem on the surface of Mars. The big problem is we have no credible information on what the gravity prescription for humans needs to be so we do not know if Martian gravity is sufficient to mitigate the problem. Next, we focused on the need for an orbiting centrifuge, we talked about the size & spin rate of the centrifuge, & what to actually test for in experiments. Dr. Jurist suggested that starting with 1/6th lunar gravity made sense because if it was sufficient, we would know that anything stronger than 1/6th would work. If not, we should probably next experiment with Martian gravity which is about 1/3rd Earth gravity. In our second segment, Dr. Jurist referred to his talking points which you will find on The Space Show blog. We went line by line so follow along with us. Despite interruptions, John stayed on topic with the talking points. Listener questions asked about how gravity & having a load on bones works & what happens in space when that load is no longer present. We talked about the time prescription as well as the load factor (G force). Toward the end, John told us about a reviewed radiation article from 2010 showing that radiation impacted bone loss so the issue in space is more complex than just microgravity. Near the end, John got a question asking about ETs & their thin, pencil like shape making them perfectly designed for microgravity. This was both an interesting & fun discussion, bordering on science fiction. Another question asked about fish, reptilian, sea mammal, & bird bones. Our final topic dealt with the release of personal astronaut medical information & others & the ways for private information to be legally released to the public. Please post your comments/questions on The Space Show blog URL above. Email for Dr. Jurist can be sent to me for forwarding.