Welcome to Our Blog
Thank you for visiting our website. We are a relatively small lab with big ideas. We are part of a much larger group of investigators known collectively as the LLUMC Molecular Radiation Biology Laboratories. It is our hope that this website will educate, communicate, and incite scientific debate. As the PI of our little group, I hope to post our data and discuss potential mechanisms, consequences, and countermeasures. With a bit of luck we'll all learn something. The links to the left include our merry band as well as collaborating investigators and laboratories. The links to the right include our archive and blogroll. The banner above will always bring you back to the main page page. Take a look around and please feel free to leave a comment on our blog (try to keep it civil and constructive) or shoot us an e-mail. - Michael " Ubertramp " Pecaut
Lab Update
Posted by: Ubertramp on 2009.02.10
Categories & Tags: Department of Energy,Grant Proposal,High-Energy Iron Radiation,Immunity,Microgravity,Mouse,NASA,NIH,New Publication,Radiation,Space Shuttle
Comments: None
Well, I’ve been on and off vacation for the last month or so. But a lot has been going on since my last update.
First, the bad news. Both NIH and DOE have turned down my grant proposals. I will probably try to resubmit the NIH grant this summer once I figure out how to address some of the reviewer concerns. I gotta keep remembering that being a scientist requires a thick skin and a short memory when it comes to rejection. Good thing I’m showing signs of early onset Alzheimer’s. Hah!
I still haven’t heard back from NASA regarding my Mice In Space proposal. I’m not sure what is holding it up. My guess is the recent economic issues have made spaceflight an even more difficult prospect than usual. Plus, they may be trying to work out a way to blend two or more proposals together. Given the lack of funds for science in general, this is probably harder than it sounds.
We also haven’t heard from LLU regarding our NMTB grant proposal. Seems LLU got a lot more proposals than they expected and they are having a harder time deciding who gets what. They may also be debating cutting the funding cap in order to fund more individual projects. I have no idea.
On to the good news. Read More..
One more time…
Posted by: Ubertramp on 2008.08.02
Categories & Tags: Bone,Brookhaven National Laboratory,Clemson,High-Energy Iron Radiation,NASA,Rats
Comments: None
As I said in my earlier post, we were waiting for a couple more publications to start showing up in PubMed. Another one hit yesterday. This one is a result of our collaboration with Ted Bateman at Clemson University. He has a great group over there looking at spaceflight effects on bone. Up until recently, he was focusing primarily on microgravity and disuse models with several biomed applicable studies. More recently, he’s shifted a bit to include radiation exposure and radiotherapy. Once his initial studies started showing some interesting results, his whole group hit the ground running and they’ve already published several papers on this exciting work. This is one of them, recently published in Radiation Research.
Bone architectural and structural properties after (56)fe(26+) radiation-induced changes in body mass.
Willey JS, Grilly LG, Howard SH, Pecaut MJ, Obenaus A, Gridley DS, Nelson GA, Bateman TA.
High-energy, high-charge (HZE) radiation, including iron ions ((56)Fe(26+)), is a component of the space environment. We recently observed a profound loss of trabecular bone in mice after whole-body HZE irradiation. The goal of this study was to examine morphology in bones that were excluded from a (56)Fe(26+) beam used to irradiate the body. Using 10-week-old male Sprague-Dawley rats and excluding the hind limbs and pelvis, we irradiated animals with 0, 1, 2 and 4 Gy (56)Fe(26+) ions and killed them humanely after 9 months. Animals grew throughout the experiment. Trabecular bone volume, connectivity and thickness within the proximal tibiae were significantly lower than control in a dose-dependent manner. Irradiated animals generally had less body mass than controls, which largely accounted for the variability in bone parameters as determined by ANCOVA. Likewise, lower cortical parameters were associated with reduced mass. However, lesser trabecular thickness in the 4-Gy group could not be attributed to body mass alone. Indicators of bone metabolism were generally unchanged, suggesting stabilized turnover. Exposure to (56)Fe(26+) ions can alter trabecular microarchitecture in shielded bones. Reduced body mass seems to be correlated with these deficits of trabecular and cortical bone.
Woot! Another Publication in PubMed!
Posted by: Ubertramp on 2008.07.30
Categories & Tags: Brookhaven National Laboratory,Clemson,High-Energy Iron Radiation,Immunity,NASA,New Publication,Props,Rats
Comments: None
Yeay! We have another publication in PubMed. Its our fourth so far this year. And we’re expecting at least two more soon. We’re also about to send out 4 more to reviewers, too. This is a banner year for us in terms of publications. Woot! These animals were irradiated at the Brookhaven National Laboratory and the work was funded through NASA and LLU’s Radiation Medicine Department. We also collaborated with Clemson on this one. The bone paper from these animals has already been published.
Here’s the abstract.
Long-term changes in rat hematopoietic and other physiological systems after high-energy iron ion irradiation.
Gridley DS, Obenaus A, Bateman TA, Pecaut MJ.
Departments of Radiation Medicine.
Purpose: To assess the long-term consequences of high-linear energy transfer (LET) iron ion radiation on immune and other critical body systems in the context of assessing potential effects astronauts may experience during exploratory missions. Materials and methods: Sprague-Dawley rats were nearly whole-body irradiated with 56-Fe (5 GeV/n) to total doses of 0, 1, 2, and 4 Gray (Gy) and euthanized 9 months post-exposure for analyses. Results: Irradiated groups consistently had low body mass. Numbers of circulating white blood cells (WBC), lymphocytes and monocytes were lower in the 2 Gy group compared to 0 Gy (p < 0.05); a trend for low granulocytes was also noted. Red blood cell counts, hemoglobin, and hematocrit were decreased in irradiated animals (p < 0.05), whereas platelet counts and volume were unaffected. In the spleen, WBC counts and DNA synthesis by T cells were similar among groups and there were no differences in secreted interferon-gamma and interleukin-6. However, trends were noted for increased splenocyte capacity to secrete tumor necrosis factor-alpha and increased level of vascular endothelial cell growth factor in plasma. One or more of the irradiated groups had significant (p < 0.05) aberrations in several blood chemistry parameters associated with liver and kidney function. Conclusion: The data show that exposure to 56-Fe radiation induced pathological changes in important body systems long after exposure.



