Re: "bacteria that can survive 1.5-million rads of gamma radiation"

[Jim Muckerheide <jmuckerheide@delphi.com>]

Jaro, others,

Do you want the Science article? 

The real significance of this, not developed in this article, is that
the "tools" that D. radiodurans uses to "protect itself" are the same
tools that are enhanced by whole-body or half-body low-dose radiation
(generally a few cGy to about 25-50 cGy) in "whole" organisms and
animals, and confirmed in some cell cultures. :-) 

These immune system, enzymatic repair/replication, and removal factors,
including cell-cycle delay and apoptosis, not only succeed in limiting
DNA damage but have limited/prevented cancers, and have actually reduced
and eliminated some cancers, in both animal studies and human clinical
applications (recently done in the US as well as Japan - despite the rad
protectionists efforts to constrain such applications!?  :-)

These are the same functions, long shown in immunology, and now
demonstrated in molecular biology, that also enable radiation to
prevent/treat, e.g., infections. (This was shown in 1896 when Schrader
at U. Missouri injected Guinea pigs with diphtheria bacillus sufficient
to cause 100% mortality in 24 hours, and to have a significant survival
fraction after several days - in response to a statement by J.J.
Thompson in the UK that the Roentgen-rays would not be bactericidal!)
plus other biological-benefit stimulations. The only "debate" was
whether this was a "direct effect" of stimulating immune functions or a
secondary effect of stimulating response to damage. 

This also includes the lack of cancers in the Taiwan population exposed
to Co-60 contamination - to an estimated 96 cGy in the first year, of
10! with an estimated mean of 4.8 cGy the first year, of now about 16
years for the majority that didn't move out - data that the rad
protectionists have failed to assess while spending $millions on blood
tests and dose estimates!?  :-)  

Berk and Hodes, 1993, Yale J Biol Med, summarized the historical
evidence for the success of using low-dose LOCAL irradiation (75-300
cGy) to treat infections as pointing to both low-dose stimulation of
immune response, and to radiation inflammation causing increased blood
flow. Unfortunately, LOCAL irradiation does not generally adequately
stimulate the immune response which is accomplished by whole-body
irradiation or half-body irradiation that includes the spleen and thymus
(or at least the spleen) at an optimum of about 10-15 cGy, repeated 2-3
times/week for 5 weeks - though absent fully developed optimization
studies, while the rad protectionists spend $10s millions on their own
controlled nonsensical epi (e.g., Hanford I-131; IARC nuclear workers;
etc.) and innumerable cell culture studies and even studies with
deficient organisms/animals that will not respond as an immunologically
whole organisms/animals.

Thanks a lot.

Regards, Jim Muckerheide
muckerheide@mediaone.net
========================

"Franta, Jaroslav" wrote:
> 
> this amazing bit of news from NUCLEAR NEWS FLASHES - Monday, November 15,
> 1999
> 
> --GOVERNMENT SCIENTISTS HAVE UNLOCKED THE GENETIC CODE OF A RADIATION-
> resistant bacteria that can survive 1.5-million rads of gamma radiation, a
> dose 3,000 times the fatal dose for a person. DOE said that dose shreds the
> bacteria's genome into hundreds of pieces but that the bacteria is able to
> repair its damaged DNA in a day. "Genetically engineering the microbe could
> lead to improved ways to clean up pollution and to new industrial
> processes," DOE said. The non-pathogenic bacteria, Deinococcus radiodurans,
> was first isolated in 1956 from samples of canned meat thought to be
> sterilized by gamma radiation. DOE-funded scientists will describe the
> bacteria's complete genetic makeup in the Nov. 19 issue of Science magazine.
> 
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