Sperm bank shortage

One of the oddest consequences of the United Kingdom's BSE epidemic of the 1990's has been the United States ban on sperm from Scandinavia.

In September 2003 the Food and Drug Administration banned the import of donor sperm from 30 countries, where Mad Cow disease has been detected in cattle - despite the fact that most scientists believe it is virtually impossible for vCJD to be spread through sperm.

Up until this point Scandinavian sperm had, apparently, been the most popular choice for US sperm bank customers who frequently seek blond haired blue eyed babies. Although the ban was enacted in 2003 it didn't really attract much attention until 2007 and 2008 when sperm banks ran out of their stocks of Scandinavian sperm.

The Science and the Sorcery

Kuru: The Science and the Sorcery

Australian scientist Michael Alpers dedicated over 50 years to researching Kuru, an obscure and incurable brain disease unique to the Fore people of New Guinea. Kuru was once thought to be a psychosomatic illness, an infection, a genetic disorder, even a sorcerer's curse, but Alpers' findings pointed to cannibalism as the culprit. Yet a recent discovery has proven to be even more disturbing: the malady is linked to mad cow disease and its human equivalent, variant CJD. With a decades-long incubation period, could a larger outbreak be on its way?

New Cases of BSE in US Raises Questions About Testing

A third confirmed case of mad cow disease in the US points out the difficulty of preventing, and even detecting, these cases under the current voluntary testing system. This testing method also makes it more troublesome to convince meat markets overseas that American beef is safe given that there is no guarantee that the beef exported is BSE free. Since this case has been confirmed, the US Department of Agriculture has been trying to track down the cow in question's herd of origin and offspring, pointing out flaws in the current testing system because this information is necessary in determining risk to the population. There is currently a fight to create a mandatory system so that there are no doubts about the safety of US beef and therefore stopping the bans on US meats when these isolated cases are identified.






http://www.csmonitor.com/2006/0315/p02s01-uspo.html

Creekstone Farms

In politics these days there is a lot of fake outrage. It's a bipartisan game and democrats and republicans are equally guilty. What worries me is that all this fake outrage seems to distract people from cases where they should be outraged

In the Creekstone Farm case even USA Today, not renowned for their radical politics, seem to be a bit shocked. The response from politicians? Deafening silence.

"In a nation dedicated to free market competition," says John Stewart, CEO of Creekstone, which is suing USDA, "a company that wants to do more than is required to ensure the quality of its product and to satisfy customer demand should be allowed to do so."

When regulators disagree with reasoning like that, you know the game is rigged.

Prion Trio

Three prion related research stories that have come out lately:

1/ Regulation of Embryonic Cell Adhesion by the Prion Protein in PLoS Biology this week.

Researchers in Germany have shown that the regular Prion protein (the one everyone has, that isn't infectious and doesn't cause problems) plays a beneficial role for the organism by helping cells communicate with one another during embryonic development. Even though we have known that a normal prion protein in the brain can turn harmful and cause deadly illnesses like Creutzfeldt-Jakob disease (CJD) in humans, and bovine spongiform encephalopathy (BSE) in cattle we did not, until this paper, know why large amounts of this normal protein are produced by our bodies in the first place.

2/ Cellular prion protein mediates impairment of synaptic plasticity by amyloid-beta oligomers in Nature a couple of weeks ago.

The regular prion protein may contribute to nerve damage if it becomes entangled with a protein fragment that scientists consider a chief suspect as a cause for Alzheimer's disease. The prion protein, if it is involved in Alzheimer's, is probably in its normal form. There's no evidence that the disease somehow releases infectious prions.

3/ Safety and efficacy of quinacrine in human prion disease (PRION-1 study): a patient preference trial in the April issue of Lancet Neurology.

The anti-malaria drug quinacrine does not appear to extend the lives of people with the human form of mad cow disease, despite encouraging results from experiments with mice. Currently there are no drugs that prevent or reverse the disease, though quinacrine has shown promise in treating prion-infected mouse cells because it can penetrate the blood-brain barrier and the drug has been effective in treating these prion-infected mouse cells by blocking the conversion of normal proteins into the abnormal disease-causing form.

Agriculture Department Seals Cow Loopholes

Obama closed a loophole in the public health system to make it permanently illegal to slaughter 'downer' cows. These cows are too sick and weak to take care of themselves. Slaughterhouses could use these cows in the food supply for other cows as long as they collapsed after inspection of a non-neurological injury. Downer cows also have a higher chance of having BSE and they lounge in feces which makes E. coli poisoning a risk as well.

http://www.msnbc.msn.com/id/29691788/

Prions and Science

Representative virus-like arrays of 25-nm particles

Non-scientists are sometimes surprised to find how open-minded science actually is. There is room for everyone - with the slight caveat that if you are going to do science you need to do it in a scientific way.

So, for example, I mentioned that although the majority of scientists now accept the prion hypothesis for diseases like Kuru, CJD and BSE, there are still a few who do not. Science is not a democracy - we don't vote for a favorite hypothesis and then make everyone accept the conclusion. Rather, one of the strengths of science is that there will always be people who are testing hypotheses even after most people accept them. This is a good thing because it either strengthens the evidence for the existing hypothesis or leads to a new, and better, one.

One of the prion hypothesis skeptics is Laura Manuelidis, a professor of neurobiology at Yale University Medical School. She believes that the prion proteins are not infectious, but are a pathological result of an infectious virus binding to this host protein. Two years ago she published a paper in the prestigious journal Proceedings of the National Academy of Sciences, Cells infected with scrapie and Creutzfeldt–Jakob disease agents produce intracellular 25-nm virus-like particles, which describes, as the title suggests, the discovery of virus-like particles in the brain tissue of animals infected with so-called prion diseases.

There is a newspaper article about her work which provides a popular summary and some response to her PNAS paper:

Neurobiologist Kamel Khalili said he has seen the electron microscopy images from the new paper and the particles certainly look like viruses.

There is a large body of evidence supporting the prion theory, albeit circumstantial, he said. "We must always keep our minds open," said Khalili, chief of neuroscience at Temple University School of Medicine.

Deadly Feasts

There are now a number of books about prions, mad cows and the whole BSE/vCJD issue. One I would recommend is 'Deadly Feasts: the "prion" controversy and the public's health' by Richard Rhodes. It covers all the known prion diseases and tells the story of their discovery and investigation. Richard Rhodes is not a scientist but a journalist and historian (he won the Pulitzer prize for 'The Making of the Atomic Bomb') and I think this gives him a bit more perspective on the issue and an impressive ability to explain scientfific issues to the general public.

Origin of BSE

A study published in PLoS Pathogens last year, BSE Case Associated with Prion Protein Gene Mutation, elucidates the origin of BSE in cattle. (PLoS stands for 'Public Library of Science' and their Journals are all 'open access' - this reverses the traditional fee structure by charging authors for publication but making the research available to everyone).

The origin of the original case(s) of BSE still remains an enigma. Hypotheses include (i) sheep- or goat-derived scrapie-infected tissues included in meat and bone meal fed to cattle, (ii) a previously undetected sporadic or genetic bovine TSE contaminating cattle feed or (iii) origination from a human TSE through animal feed contaminated with human remains.

The paper describes a novel mutation in a prion protein gene in a cow that is similar to the mutation in the human genome that causes the genetic form of CJD. This suggests that the BSE epidemic could have begun by a random genetic mutation. If that is the case then there are implications for the US beef industry. Concentrating on keeping out infected cows isn't a bad idea but should not be the only strategy since spontaneous cases of BSE will appear. The important point is to prevent the multiplication via cow cannibalism of those spontaneous cases that occur.

Scary Squirrel World

Until we know more about TSE's it would seem wise to hold off on all those wild animal brain based delicacies. It seems likely that many organisms may have such TSE's but if the species lifespan is only a few years it may be much shorter than the time it takes the prion protein to multiply up to the level that causes symptoms.

Following the observation of an unusual cluster of Creutzfeldt-Jakob cases in Kentucky, the suggestion was made that these may have arisen due to the consumption of squirrel brains - apparently a regional delicacy.

These observations, together with recent concerns about the transmission of a unique encephalopathy in man believed to be related to bovine spongiform encephalopathy led us to examine the possible association of eating squirrel brains with CJD in rural Kentucky, where eating squirrel and other small game is not uncommon. Culinary preparations include scrambling the brains with eggs or putting them in a meat and vegetable stew referred to as “burgoo”.

Normally I dislike the very dry style of scientific writing but this paper, Creutzfeldt-Jakob Disease and eating squirrel brains, contains the following gem:
'(C)aution might be exercised in the ingestion of this arboreal rodent.'

Following Mike Huckabee's revelation that he ate squirrel (cooked in a popcorn popper!) in college Slate investigated.

US can block mad cow testing

I almost missed this. An appeals court ruling coming out right before the holiday weekend. AP had the story but I didn't notice it on Friday.

The Bush administration can prohibit meat packers from testing their animals for mad cow disease, a federal appeals court said Friday.

A federal judge ruled last year that Creekstone must be allowed to conduct the test because the Agriculture Department can only regulate disease "treatment." Since there is no cure for mad cow disease and the test is performed on dead animals, the judge ruled, the test is not a treatment.

The U.S. Court of Appeals for the District of Columbia Circuit overturned that ruling, saying diagnosis can be considered part of treatment.

Mad Cow

If I could be bothered I would have a t-shirt made that says 'Ask me anything about mad cow disease.' But I'll probably never get around to it so let's just pretend I have one. We didn't have much time to cover mad cow disease but I'm glad I was able to squeeze it into 20 minutes of summer's hectic schedule. If you have any questions about it please catch me in office hours or before or after lecture or by e-mail. As part of that generation that could have been killed it is a topic that has been of great interest to me. I'm also reminded of the subject every time they have a blood drive on campus (eg this week). There's something about knowing that your blood is considered too risky to be collected that brings the whole issue home. Even my wife who only spent a couple of years in England is not allowed to give blood.

As I think I wrote on an earlier post I'm not a vegetarian and don't have any particular agenda here. On the other hand, in the interests of full disclosure, I should say that since first doing some research about this issue in the mid-1990's I haven't actually felt like eating red meat....

Mad Cow USA

The New York Times had an article on Mad Cow disease and the fate of the US beef industry in June this year. It's a nice update of the current state of affairs in the US.

Relevant material previously on the blog:
Mad Cow USA
Sexually transmitted Lyme Disease ?
World's worst mouse plague

House grills meat packing chief

Westland/Hallmark Meat Co. President Steve Mendell and attorney Asa Hutchinson, left, wait to testify on Capitol Hill in Washington, Wednesday, March 12, 2008, before the House Oversight and Investigations subcommittee hearing on federal regulations for food and food safety.

When faced with video showing sick cattle being illegally slaughtered the head of the Southern California slaughterhouse at the center of the largest beef recall in U.S. history was forced to acknowledge that his earlier statement, made under oath, that no ill cows from his plant entered the food supply was incorrect. Although the video was widely circulated and available at many sites on the internet Mendell avoided a perjury charge by claiming he had never seen it. This is the video that led to his plant's shutdown and last month's recall of 143 million pounds of beef and he had never bothered to watch it?

This story was all over the news today. Best headline goes to the Chicago Tribune:
House grills meat packing chief.

Largest Beef Recall in US History...too late?

The 143 million pounds of beef that were recalled this February have most likely already been consumed by...us! The Westland Hallmark Meat Packing Plant was investigated after the Humane Society accused this plant of abusing cows that were unable to stand. Videos show workers dragging cattle with chains, jabbing them with fork-lifts, and using electric shock on the cows in order to move them to be slaughtered. Beyond the atrociousness of these inhumane acts, the fact that these "downed" cows were slaughtered and sold is a serious threat to the American meat eaters because as we know, difficulty with balance and eventually, the inability to stand are symptoms of mad cow disease. Since the release of the video, the plant has been shut down and the two workers on the video are now facing charges of animal cruelty (however, the plant as a whole has no such charges). So...maybe hold off on the burgers for a while? For more: Click Here

To watch the video: Click Here.

Mad Cow Disease in Canada

Canada confirmed a new case of mad cow disease on Tuesday, the 12th. The animal in question was a six-year-old dairy cow from Alberta that had most probably eaten infected feed. The Canadian Food Inspection Agency, which vows to eradicate bovine spongiform encephalopathy (BSE) within a decade, has consistently said it expects to find a few cases of the disease. The CFIA said no part of the animal had entered the human or animal food supply. The cow was born after Canada and the United States introduced a ban in 1997 on cattle feed that contained ingredients made from rendered cattle and other ruminants. At least four other cases have involved animals born after 1997. "Many trading partners in the past have shut their borders to Canadian cattle and beef products after the first home-grown case in 2003, dealing a massive blow to the industry, and Ottawa has fought hard to restore market confidence. Last May the World Organization for Animal Health relaxed its security rating on both the United States and Canada, classifying both nations as controlled risk in a sign it was happy with their efforts to combat BSE. "This case will not affect Canada's controlled risk country status," the CFIA said in a statement. "Based on science, it is not expected that this case should impact access to any of Canada's current international markets for cattle and beef." Mexico noted last Friday that it would soon lift a ban on Canadian cattle imports that dated back to 2003. Here's the link to the article.

Mad Cow USA

I think it is fair to say that the Organic Consumers Association is not exactly without an agenda, however since the Mad-Cow disease Homepage moved their daily news listing over there they have also become one of the best sources for information on BSE, CJD and all thing mad and bovine. If you think the story is over, well it might just be getting started. FYI, I'm not a vegetarian, but since doing some research about BSE a little over 10 years ago and finding out about how the whole industrial food process works I just haven't felt like eating beef.....