catbirdseat

Did you ever wonder how Strongbad manages to type so well while wearing boxing gloves?

I don't think so. Proteins don't cross intact skin at all. If meat handlers did not use gloves and did not wash their hands, they could possibly ingest some by putting hands in their mouths, but this route would be less likely to cause infection than actually consuming the meat. In answer to JayB's question this experiment has been done: "Using in vitro conversion of radiolabeled PrPC to protease-resistant PrP by incubation with PrPSc preparations of either strain, Bessen et al. (1995) could confer the respective properties to the newly converted protease-resistant PrP." Biology and Pathology of Prion Diseases: Hypothesis on the Nature of the Infectious Agent

"It would be amazing to me if there was a protein out there that could survive being cooked, resist degredation by pepsin and acidity in the stomach, pass through the intestine intact, pass into the bloodstream as an intact protein rather than a polypeptide, exist in the bloodstream as an intact foreign protein witout provoking antibody generation, make it through the liver unmodified, ultimately be transported from the bloodstream and across the cell membrane, and then persist in the cells without being tagged by kinases for import into lysozomes for destruction, or attack by proteases in the cytosol. " Jay, PrP(Sc) is such a protein. The article you cited is significant. It means that you can test more easily which species prion diseases are transmissible to humans by doing it in vitro rather than by attempting to infect animals. Obviously, there aren't any humans lining up to see if sheep prion (scrapie), or cattle prion is infectious.

Blasphemous!

There is something like that at Vantage, but there is no access from the bottom and it is full of pigeon shit.

Are there any chimneys in the natural world that are true shafts, like their namesake, rather than being open on one side?

Classic.

Did he mention unknown knowns? That's the only permutation that doesn't exist.

Ehmic, are you familiar with the concept of "autocatalysis"? That's what it is. A, the normal protein, is converted to B, the abnormal one. The reaction can't go by itself, it is kinetically unfavorable (although it is thermodynamically favorable), but will go in the presence of a catalyst. In autocatalysis, the product, B, is the catalyst. So B catalyzes the production of itself from A. The more B, the faster A is converted. Wicked.

Aluminum crampons will bite into ice if they are sharpened. All crampons need to be sharpened eventually. I'll bet your friend will remember to sharpen his crampons the next time.

If it was me, I'd take it easy for a week, take naproxen sodium and see whether the hip was starting to feel better. If not, I'd go to the doctor.

Klenke was literally two feet from reaching the summit when he found a spruce trap (or should I say a Mountain hemlock trap?). His snowshoe plunged into a four foot deep hole.

Of course I did. You said you didn't care.

I don't think it detracts one bit from the impact of your post to credit the source. It's no skin off your teeth, and besides it allow other people to go find other funny writings by the same author if they enjoyed the reading.

All kidding aside, do I think Americans should worry about eating beef? I think the answer is no. Your chances of getting VCJD are much less than getting cancer or getting struck by lightning. People should not change my habits based on the discovery of one infected cow.

Prion disease is a complex subject that I have followed closely since I happened upon some of Stanley Prusner's articles back in the mid '80's. It is not caused by viruses as prions do not contain DNA. They are a conformationally altered variant of a naturally occurring brain protein. No one knows what the function of this protein is, but it is associated with cell membranes of neurons. When prion protein comes into contact with native protein, it acts as a "scaffold" or template, if you will, to convert the normal protein to the altered state which is characterized by beta-pleated sheets. The prion proteins form self-associating aggregates which eventually grow large enough to form granules that can be seen in elecctron micrographs. All this eventually leads to death of neurons and "spongiform" lesions in the brain. The protein does not circulate in the blood stream in large concentrations, so therefore it is difficult to detect without taking a brain biopsy. There are tests being developed that can detect the prion before visible symptoms develop. The protein is tremendously stable and can survive proteases and autoclaving. In fact, infectious prion material was recovered from garden soil outside a lab where it had been poured three years before! The only way to kill it is to incinerate it. Since the normal prion protein of pigs is different from that of cows and humans, there is what is termed a "species barrier". Apparently, this barrier is high for cow to pig transmission. There is a species barrier between cows and humans too, but apparently there is a subset of individuals who possess certain protein genotypes that are more susceptible to transformation. In other words, not everyone who eats contaminated beef can get the disease called Variant Creuzfeldt-Jakob. When prion diseases were traced to recycled animal parts, it seemed clear that this practice should be stopped immediately. However, what actually happened was the feed producers asked the question, "do all animal parts harbor the prion or just some parts?". The scientists answered that "we think it is found mostly in nervous system tissue and bone." So what they did was to exclude bone, brain and spinal cord from the feed, but continued to use blood, and meat, etc. All they did was reduce the chance of infecting an animal with their feed, not eliminate it. Now comes the time of reckoning.

Haven't you ever heard of a "Born Again" Sprayer?

This is your brain. This is your brain on beef. Any questions?

I am glad that I stopped eating red meat over 20 years ago. At last count 134 Britons have died from Variant Creutzfeldt-Jakob Disease. Now they are dying in Canada. The United States is next.

"I had my pacemaker dialed in to the highest setting." --remarks by Cheney after successful game hunt

It's all coming soon.

I saw that. That is the stupidest thing I have seen in a truck commercial. When you load a truck, you load it pretty close to capacity. When you drop a load into a truck from four feet, it is like loading the truck with several times the static load limit. I wonder if they used fake timber, or if they went ahead and wrecked the truck they used in the commercial. At the very least, it would have broken some leaves in the springs, blew out the shocks and possibly bent the axle.

Take the test again under a pseudonym and deliberately try to flunk, or else answer at random and see what you get.

It ain't called "double U" for nothing.