RE: Laymans questions on hormesis and LNT

[John Jacobus <crispy_bird@YAHOO.COM>]

Jim,

I am not sure if I get your point.  Why should error

free repair only occur at low dose rates?  Why does

high biological stress, but not low biological stress,

cause different gene responses that lead to

error-prone repair?  It is an interesting idea, but

are there any studies that show the differences beyond

the magnatude of the effects of the radiation?



Whether we like it or not, I do think that the

prevention of DS breaks (beyond the natural background

rates) will replace increased cancer rates as the

regulatory criteria.



--- "Muckerheide, Jim  (CDA)"

<Jim.Muckerheide@state.ma.us> wrote:

> John,

> 

> Right. DSB disinformation is used to support the

> LNT. 

> 

> But DNA damage is irrelevant. Long-term effects

> (e.g., cancer) are due

> to failure of repair and removal of damaged

> cells/tissues. 

> 

> Replicated results confirm that LDR stimulates DNA

> repair enzymes and

> genes (even in cancer-prone individuals) that

> produce error-free repair

> (plus stimulate lymphocytes and other immune cells

> and molecules, which

> enhances health by affecting the non-rad damage and

> latent damage).  HDR

> adds negligible "DNA damage" but the high biological

> stress causes

> different genes to be expressed that cause

> error-prone "emergency"

> cellular repair modes that produce a legacy of

> latent damage. (That

> latent damage is also reduced by later LDR

> exposures/treatments.) 

> 

> Regards, Jim Muckerheide

> 

> 

> -----Original Message-----

> From: John Jacobus [mailto:crispy_bird@yahoo.com] 

> Sent: Monday, September 15, 2003 9:34 AM

> To: Ted Rockwell; radsafe@list.vanderbilt.edu; Cary

> Renquist

> Cc: Muckerheide-MA

> Subject: RE: Laymans questions on hormesis and LNT

> 

> 

> Ted,

> I think we agree that the use of DS breaks is not a

> guide to regulation limits.  Unfortunately, I have a

> feeling that is what will happen.

> 

> --- Ted Rockwell <tedrock@starpower.net> wrote:

> > >then you

> > justified in regulate exposures to prevent DS

> > breaks.

> > 

> > John:

> > 

> > You cannot regulate to prevent DS breaks unless

> you

> > outlaw normal

> > metabolism.  That's what causes the overwhelming

> > majority of DS breaks.

> > 

> > Ted Rockwell

> > 

> > 

> > -----Original Message-----

> > From: owner-radsafe@list.vanderbilt.edu

> > [mailto:owner-radsafe@list.vanderbilt.edu]On

> Behalf

> > Of John Jacobus

> > Sent: Sunday, September 14, 2003 4:21 PM

> > To: Ted Rockwell; radsafe@list.vanderbilt.edu;

> Cary

> > Renquist

> > Cc: Muckerheide-MA

> > Subject: RE: Laymans questions on hormesis and LNT

> > 

> > 

> > Ted,

> > You are missing the point of my argument.  What I

> > was

> > saying is if you declare that it radiation causes

> DS

> > breaks are detrimental to cell functions, then you

> > justified in regulate exposures to prevent DS

> > breaks.

> > I am saying that you are not.  As I said, just

> > because

> > you can detect an effect does not mean it should

> be

> > used as the basis of regulations.  Simply stated,

> DS

> > breaks can be (1) repaired (2)exist but do not

> have

> > effects of cell functions, (3) cause cell death,

> or

> > (4) lead to cancerous growths.  All are possible,

> > but

> > only the last should be regulated against. 

> However,

> > how do differentiate between the DS breaks?  I say

> > regulations should be based on factors other than

> > the

> > formation of DS breaks.

> > 

> > I think you are looking to defend hormesis without

> > understanding my comments.

> > 

> > . . .

> 

> =====

> "May we never confuse honest dissent with disloyal

> subversion." 

> 

> Dwight D. Eisenhower  

> 

> -- John

> John Jacobus, MS

> Certified Health Physicist

> e-mail:  crispy_bird@yahoo.com

> 

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=====

"May we never confuse honest dissent with disloyal subversion." 



Dwight D. Eisenhower  



-- John

John Jacobus, MS

Certified Health Physicist

e-mail:  crispy_bird@yahoo.com



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