AW: [ RadSafe ] Danger of ADJACENT HIGH-Dose Radiation

[HOWARD.LONG at comcast.net]

RE: 2007 Marie Curie Prize Paper by M. Tubiana 

Wednesday, August 20, 2008 10:59:56 AM 
Howard:
 
Not sure I understand your e-mail.  The paper is scheduled to be published in September. Dr. Tubiana may be a bit hesitant to having the proofs version discussed on Radsafe digest. Once officially published then anyone could comment on Radsafe about the paper and it would be available to all who have interest.
 
Bobby
 

This response from Bobby Scott explains my unwillingness to comment on Tubiana's work yet, John.

Since we don't even know what causes cerebellar cancer one cannot reasonably suggest that  low dose radiation benefit may be disproven by an indirect association with high dose radiation.
Where does hormesis come into this, Ranier and John? 

Howard Long


-------------- Original message -------------- 
From: <Rainer.Facius at dlr.de> 

> Dear John, 
> 
> the article by Mancuso et al. (2008) has been discussed here with respect to its 
> improper use of the term "bystander effect" instead of the proper and long 
> established term "abscopal effect" and with respect to the dose the cerebellum 
> of the shielded mice did receive due to finite attenuation of the shields and 
> due to backscattering from the body of the mice. Furthermore it was pointed out 
> that the findings from this experiment are irrelevant regarding low dose 
> radiation protection issues. 
> 
> To my knowledge, in this discussion the term hormesis has not been mentioned at 
> all but once by myself. I drew attention to the fact (fig. 2D and fig. S1 of the 
> supplement) that the data by Mancuso et al. exhibit the lowest (in fact zero) 
> incidence of medulloblastoma not for the un- or sham irradiated animals but for 
> those unshielded animals which were exposed to a uniform whole body dose of 36 
> mGy, i.e., that dose which the cerebellum of the partially shielded mice 
> received from stray radiation. 
> 
> I agree that - in my view - Howard Long occasionally is straining the evidence 
> in favour of hormesis - just as you are trying to ignore or depreciate it. This 
> time however I am the one who is guilty of introducing the incriminated word - 
> though I mentioned it only casually at the very fringe of the discussion. 
> 
> Best regards, Rainer 
> 
> Dr. Rainer Facius 
> German Aerospace Center 
> Institute of Aerospace Medicine 
> Linder Hoehe 
> 51147 Koeln 
> GERMANY 
> Voice: +49 2203 601 3147 or 3150 
> FAX: +49 2203 61970 
> 
> -----Ursprüngliche Nachricht----- 
> Von: radsafe-bounces at radlab.nl [mailto:radsafe-bounces at radlab.nl] Im Auftrag von 
> John Jacobus 
> Gesendet: Sonntag, 24. August 2008 23:43 
> An: radsafe at radlab.nl 
> Betreff: RE: [ RadSafe ] Danger of ADJACENT HIGH-Dose Radiation 
> 
> I wonder how many others on this list have read the article. I am sure Dr. Long 
> has not. I would be nice to see a discussion of the study as opposed to a 
> summary dismissal as it may go against the belief in hormesis. Is that too much 
> to ask for? 
> 
> +++++++++++++++++++ 
> "Part of human nature resents change, loves equilibrium, while another part 
> welcomes novelty, loves the excitement of disequilibrium. There is no formula 
> for the resolution of this tug-of-war, but it is obvious that absolute surrender 
> to either of them invites disaster." 
> -J. Bartlet Brebner 
> 
> -- John 
> John Jacobus, MS 
> Certified Health Physicist 
> e-mail: crispy_bird at yahoo.com 
> 
> --- On Thu, 8/21/08, Cary Renquist wrote: 
> 
> From: Cary Renquist 
> Subject: RE: [ RadSafe ] Danger of ADJACENT HIGH-Dose Radiation 
> To: "NIXON, Grant" , radsafe at radlab.nl 
> Date: Thursday, August 21, 2008, 1:16 PM 
> 
> The distances involved in this experiment seem too far for diffusion of 
> radicals. 
> What I understand (grok [for the geeks out there]) from the few papers that I 
> have read... 
> Acute "low-level" exposures seem garner signal transduction responses that favor 
> cell death or very basic repair attempts. Acute "high-level" 
> exposures seem to result in signal transduction responses that favor 
> (emergency) repair mechanisms. 
> In this experiment, it seems that the (emergency) repair mechanisms are being 
> triggered in the shielded area -- the repairs are either acting on damage caused 
> by the low-level scatter or the normal damage caused by cellular processes. 
> 
> I see that normal wild-type mice in the experiment did not display any 
> carcinogenic response -- only the patch1 mice. Normal mice did show short term 
> effects that seemed to be evidence for the transmission of the high-exposure 
> response to the shielded areas. 
> 
> C. 
> 
> --- 
> Cary Renquist 
> RSO, Eckert & Ziegler Isotope Products 
> Office: +1 661-309-1033 
> cary.renquist at ezag.com 
> 
> -----Original Message----- 
> From: radsafe-bounces at radlab.nl [mailto:radsafe-bounces at radlab.nl] On Behalf Of 
> NIXON, Grant 
> Sent: Wednesday, 20 August, 2008 13:09 
> To: HOWARD.LONG at comcast.net; ROY HERREN; radsafe at radlab.nl 
> Subject: RE: [ RadSafe ] Danger of ADJACENT HIGH-Dose Radiation 
> 
> To add to Howard's comment: 
> 
> Perhaps the mechanism for the DNA damage to adjoining tissue (the so-called 
> "bystander effect") is nothing more than a propagated free-radical reaction 
> having nothing to do with cell-to-cell communication. The high doses would 
> liberate such large numbers of free-radicals that the affected perimeter of 
> affected tissues would increase on physical grounds alone (diffusion theory 
> coupled with target theory). The "chemical that blocks cell-to-cell 
> communication" may simply be a free-radical scavenger. 
> 
> Grant I. Nixon, Ph.D., P.Phys. 
> Science Specialist (Dosimetry/Physics/Engineering) BEST Theratronics 
> 413 March Road 
> Ottawa, ON K2K 0E9 
> Canada 
> tel. (613) 591-2100 x2869 
> fax. (613) 591-2250 
> 
> -----Original Message----- 
> From: radsafe-bounces at radlab.nl [mailto:radsafe-bounces at radlab.nl] On Behalf Of 
> HOWARD.LONG at comcast.net 
> Sent: Wednesday, August 20, 2008 12:36 PM 
> To: ROY HERREN; radsafe at radlab.nl 
> Subject: [ RadSafe ] Danger of ADJACENT HIGH-Dose Radiation 
> 
> So, "high dose radiation - 12,000 times - chest x-ray" affects adjacent tissue? 
> Would other severe injury, like crushed arm, affect the rest of the body? Of 
> course! 
> 
> Why the surprise? 
> 
> Why the false headline that it "Hints at Dangers of Low Dose Radiation"? 
> 
> Hormesis, low dose good where high dose bad, must be taught. 
> We must correct this disinformation by fearmongers to dismantle over-regulation 
> and liberate nuclear power. 
> 
> Howard Long 
> 
> -------------- Original message -------------- 
> From: ROY HERREN 
> 
> > http://sciencenow.sciencemag.org/cgi/content/full/2008/818/3 
> > 
> > Bystander Effect" Hints at Dangers of Low-Dose Radiation 
> > 
> > By Jocelyn Kaiser 
> > ScienceNOW Daily News 
> > 18 August 2008That lead apron you wear during a dental x-ray is 
> supposed to 
> > protect the rest of you from radiation. But it may not work very well, 
> according 
> > to a new study. When cancer-prone mice were placed in lead containers 
> and 
> > irradiated on just the lower half of their bodies, they developed 
> brain tumors. 
> > The results suggest that radiation could be riskier than scientists 
> thought. 
> > The study builds on a surprising effect, first observed 16 years ago. 
> When cells 
> > in culture are exposed to ionizing radiation, even those not directly 
> hit 
> > sustain damage to chromosomes. Apparently, the irradiated cells pass 
> on a 
> > distress signal or emit some chemical that breaks the DNA of 
> neighboring cells 
> > (ScienceNOW, 7 September 2005). Although this "bystander effect" 
> has 
> been 
> > observed in tissue culture and recently in living animals, no 
> experiments have 
> > yet linked it to the main reason for concern: Bystander effects might 
> trigger 
> > cancer. Some scientists even suspect the opposite--that the bystander 
> responses 
> > could protect against the disease by killing damaged cells. 
> > Now it seems that the cancer risk is real. Radiation oncologist Anna 
> Saran at 
> > the Italian National Agency for New Technologies, Energy and the 
> Environment in 
> > Rome and colleagues studied mice with a mutation in a gene called 
> Patched that 
> > makes them susceptible to brain tumors early in life. They placed 
> newborn mice 
> > in lead shields that protected their heads and upper bodies, then 
> zapped them 
> > with high-dose x-rays, or about 12,000 times the dose of a dental or 
> chest 
> > x-ray. The scientists found that the cerebellums of these animals had 
> higher 
> > than normal amounts of DNA damage and apoptosis, or programmed cell 
> death. By 40 
> > weeks of age, 39% of the shielded mice had developed brain tumors. 
> That's a lot 
> > considering that the rate was 62% in Patched mice that were irradiated 
> all over, 
> > including their heads. Patched mice that weren't irradiated did not 
> develop 
> > brain cancer. 
> > When the team injected the shielded mice with a chemical that blocks 
> > cell-to-cell communication before irradiating them, they detected no 
> DNA breaks 
> > and the amount of apoptosis decreased more than threefold. Even though 
> the 
> > irradiated tissues are far away from the brain, they are connected by 
> neurons 
> > that could be passing on bystander signals, Saran says. The results 
> appear 
> > online this week in the Proceedings of the National Academy of 
> Sciences. 
> > "This is a milestone paper," says Columbia University radiation 
> physicist David 
> > Brenner. He suggests that current estimates of cancer risk from low 
> doses of 
> > radiation--say, from naturally occurring radon and diagnostic 
> tests--may 
> > underestimate the danger by failing to take into account bystander 
> effects. To 
> > learn more, however, the mouse work should be repeated with lower 
> doses of 
> > radiation, Saran says.