• Quick note - the problem with Youtube videos not embedding on the forum appears to have been fixed, thanks to ZiprHead. If you do still see problems let me know.

Prions: testable? traceable?

Suezoled

Illuminator
S
Joined
Sep 20, 2003
Messages
4,477
Okay, so a mad cow was found in the US, or at least a cow that tested positive for Mad Cow Disease. How does one test for these things? Is it possible to test for prions themselves while they lay dormant, or does one have to wait until some symptoms manifest themselves before testing?

Also, it was mentioned that dead cows are fed to live cows, so that's how the prions are passed from one host to another. This only reminds me of on saying" Soylent green is made of people!"

Okay, now that that's out of system... I feel better. ;)
 
You may find studying the dynamics of the prion disease Kuru (now extinct or believed to be extinct) of interest for more information. Here is the intro to the following website. (search term: KURU). Another prion disease is SCRAPIE found mostly in sheep. Prion diseases are also found indeer and elk where it is called Chronic Wasting Disease or CWD. In cattle it is called BSE or Bovine Spongiform Encephalopathy.


http://www.as.ua.edu/ant/bindon/ant570/Papers/McGrath/McGrath.htm




"This particular group (South Fore tribes on PNG) was partaking in ritual acts of mortuary cannibalism, and this conduct was later held to be responsible for the transmission of the fatal kuru epidemic. This distinctive aspect of the illness made it even more fascinating to the various Western scholars who devoted their time to conquering it. Many efforts have been made to understand and describe kuru, and the knowledge of the dynamics of the disease has continued to grow, even though the disease all but disappeared in New Guinea with the termination of cannibalism. The pathology and symptoms of kuru are of specific interest here, as well as a comparison of kuru with other prion diseases. Scientists have now identified kuru as a prion disease. Understanding the structure and replication of the prion is crucial to interpreting the dynamics of kuru and several other prion diseases, which exist today. The onset of kuru led to a study of an unfamiliar disease that has lasted almost five decades. This particular disease serves as an example of the procedures scientists undergo in order to understand and appreciate all of the aspects of a disease and how potential therapies and solutions can be found."


For testing, see:

http://www.innovations-report.com/html/reports/agricultural_sciences/report-13789.htm

"The test, an immunological probe, or "immunoassay," uses a novel strategy and newly developed, high-affinity antibodies to reveal and measure prions in brain tissue. As a result, it is able to directly measure infectious, abnormal prion protein."
 
Well turns out the cow was imported from Canada...that opens up a whole nother can O' prions. This thing is going to get a lot worse before it gets better =(
 
Some of what has been discussed about the meat packing industry after this has been, uh, a BIT disturbing. For instance, they allow a sick cow's meat to enter the food stream before BSE tests are complete. Not a good idea, imho.

Also, the way meat was extracted for cold cuts and other processed meats was a bit of a suprise, to me. Apparantly they used to crush the spine and some other bones where the meat was difficult to manually remove. During the pressing some spinal nerve material would extrude and be used along with the skeletal muscle. YUM! I don't believe they do this any longer, though.

Anyway, I've been eating turkey-based cold cuts for years (and I'm sure they use equally appetizing extraction techniques for that), and I'm not aware of any bird-based prion diseases so far.
 
Its very hard to test for prions, which it must be said are the presumed agent. There certainly is no test that can be carried out in a routine manner. Even if we had a test, who would want to know that they carried an agent that could be fatal within a number of years. The prospects of treatment are very low. Who knows how many people could be carrying the prions, and how many of them would go on to develop the disease. It would be impossible to put over the risk to the public. Some would want to know, others would not.

The current tests rely on brain tissue biopsys so are not really practical for a screening test.

PJ
 
I would think a test would be valuable, to at least rule out CJD in a person exhibiting signs of mental degradation. The article SteveGrenard linked stated that human tests is an eventual goal, and I can see the diagnostic value of those.
 
Ahhh... Just the topic for me.

There are 2 ways to test for prions.

One is an initial assessment way.

The other is kind of a genetic test...

The initial assessment way is to look and see if the brain is ridden with holes via a mircroscope.

If it turns out there is, there is a pretty good chance that the cow had some form of a TSE.

The genetic way is a bit more complicated.

Here are some good sites in describing how it is tested for via genetics:

http://www.biomedcentral.com/news/20021021/05


And here is a link to a type of test that is currently being worked on right now:

http://www.sciam.com/article.cfm?articleID=0009E954-1983-1C68-B882809EC588ED9F
 
Wait...

Isn't a prion a small self-replicating organism?

I remember hearing they can see atoms, how can they not see organisms made of billions of them?

-INRM
 
It is a mis-twisted protein. It "replicates" by twisting like proteins into twisted proteins. The proteins that BSE uses are in the brain and spine.
 
Does anyone know how the prion diesease in deer spreads? Unlike cows, deer shouldn't normally be in a situation where they are likely to eat brain or spinal tissue from another deer. So how do they get the disease? Are their other vectors or does an error occure in the the protien spontaneously?
 
The disease probably erupted in farmed elk herds and was only first identified in 1997. Little is, therefore, known about how it first occurs in deers. The fact that it was found in farmed herds of cervid animals means they were probably fed the same type of cattle feed fed to cattle which could potentially result in the spread of prions to them and evidently did, but it is impossible now to trace this back or get anyone (e.g. deer/elk farmer) to admit to this......but they're working on it.

The following website has an extensive FAQ and discussion of prion disease in cervids.

http://www.health.state.mn.us/divs/idepc/diseases/cwd/


Also this advisory from the USDA succintly summarizes the history to date:

L. H. Creekmore
USDA-APHIS-VS
National Animal Health Programs Staff
Fort Collins, CO
CWD was first detected in farmed animals in the United States in 1997 in an elk herd in South Dakota. Since then the disease has been identified in 23 additional farmed elk herds and one farmed deer herd in a total of eight States (CO, KS, MN, MT, NE, OK, SD, WI). These herds were discovered through routine surveillance, tracing, and depopulation efforts. Thirteen of these positive herds traced back to three source herds, one in SD, one in MT and one in CO. Five positive herds were located in or near endemic areas where CWD occurs in wildlife and have no known relationship to other known positive herds. Three positive herds were detected in August and September of 2002. Epidemiological investigations to understand the source of infection of the herds associated with the endemic area as well as the newly identified herds are continuing. Since 1998, twenty- one of these herds have been removed; about half of these were depopulated in the past year with the use of USDA funds. In addition to these positive herds, USDA assisted in the depopulation of elk herds within the endemic areas of Colorado and Nebraska. Of the four remaining herds, one in Nebraska has had its quarantine lifted after more than four years of surveillance with no further evidence of the disease. A second herd in Colorado is being reviewed for inclusion in a State research program. Plans for depopulation of the last two herds, one in MN and one in WI are underway.
 
Steve,

Do you have any knowledge of this at all, or are you simply going to cut&paste, reiterating what others have written?

We can all do a Google, you know.
 
Hmmm. That makes sense. I hadn't thought about wild deer eating cattle feed. Sometimes feed is brought to pastures so deer would have opportunities. That might also imply that cows in the US were being feed infected feed.

Of course that could have some interesting implecations for the safety of US beef.
 
http://www.mercola.com/2000/jul/23/diseased_meat.htm

This is the article that I showed a few people before I became a vegetarian in 2000.

(Is this the reason I became a vegetarian? Actually, no. It was my cover story for becoming one to hide my true motives -> trying to get closer to, horror of horrors, a vegan.

Still and all, if it weren't for that, I wouldn't have discovered my real true love: Indian Food!)


Anyways, back on top: it's my understanding that we've all got prions in our brains -> strand of protein in certain configurations.

The problem is with abnormally-shaped prions; prions twisted in ways that that cause CJD to show up in the brain. The abnormal prions cause other prions to shape themselves abnormally, and somehow, all these ab-prions cause your brain to turn to swiss cheese.
 
bignickel, that link really doesn't say much about prions or things... unless I was missing something?
 
I was editing my post just as you were typing. So that I could actually throw in a bit about prions.

The whole prion thing brings up the issue of beef testing, so I guess the article's main thrust is about how meat inspection is done. And that the article is almost 4 years old.

Having the dead's cows beef 'in the system' AFTER the testing shows positive for 'mad cow' is probably not a good thing, to say the least. But that topic would be better covered in more recent articles, which I would track down (if it wasn't for the fact that the issue is so hot that most of us have already read those articles).
 
bignickel said:
I was editing my post just as you were typing. So that I could actually throw in a bit about prions.

The whole prion thing brings up the issue of beef testing, so I guess the article's main thrust is about how meat inspection is done. And that the article is almost 4 years old.

Having the dead's cows beef 'in the system' AFTER the testing shows positive for 'mad cow' is probably not a good thing, to say the least. But that topic would be better covered in more recent articles, which I would track down (if it wasn't for the fact that the issue is so hot that most of us have already read those articles).
Click to expand...

Oh, okay. I was looking at the site and read the article and said to myself "am I staring the bull in the face and not realizing it?"
:D
 
BTox said:


Just a IMO, but I would put NO credibility to any article on Mercola's site.
Click to expand...

I think Mercola's site finds information and displays it, but it doesn't seem as if he checks his sources. Also, he himself is trying to sell something, and that make me wonder about favoritism in articles.
 
About other vectors.

CWD appears to have come from farmed elk here in Saskatchewan, and has now been found in 16 wild animals ( of 11,000 brains tested). Transmission vectors are still not completely known, it appears to be from mother to calf, but...

One farmer whose herd was destroyed has had his farm indefinitely quarantined not but fiat, but by delay. He can't get word on what he has to do to use his pasture after a five year quarantine, not even replacing the soil
(and what does he do with contaminated soil?). It appears that the food inspection agency is worried about prions being transmitted through urine and feces. Density of population would be a major contributor if that is the case, which really makes me wonder about cattle in feed lots.
 
You must log in or register to reply here.

Back
Top Bottom