Kaleidoscope 2: 2010 wk 31

8 08 2010

Almost a year ago I started a new series Kaleidoscope, with a “kaleidoscope” of facts, findings, views and news gathered over the last 1-2 weeks.
It never got beyond the first edition. Perhaps the introduction of this Kaleidoscope was to overwhelming & dazzling: lets say it was very rich in content. Or as
Andrew Spong tweeted: “Part cornucopia, part cabinet of wonders, it’s @laikas Kaleidoscope 2009 wk 47”

This is  a reprise in a (somewhat) “shorter” format. Lets see how it turns out.

This edition will concentrate on Social Media (Blogging, Twitter Google Wave). I fear that I won’t keep my promise, if I deal with more topics.

Medical Grand Rounds and News from the Blogosphere

Life in the Fast Lane is the host of this weeks Grand Rounds. This edition is truly terrific, if not terrifying. Not only does it contain “killer posts”, each medblogger has also been coupled to its preferred deadly Aussie critter.
Want to know how a full time ER-doctor/educator/textbook author/blogger/editor /health search engine director manages to complete work-related tasks …when the kids are either at school or asleep(!), then read this recent interview with Mike Cadogan, the founder of Life in the Fast Lane.

Don’t forget to submit your medical blog post to next weeks Grand Rounds over at Dispatch From Second Base. Instructions and theme details can be found on the post “You are invited to Grand Rounds!“ (update here).

And certainly don’t forget to submit your post related to medical information to the MedLibs Round (about medical information) here. More details can be found at Laika’s MedLibLog and at Highlight Health, the host of the upcoming Edition.
(sorry, writing this post took longer than I thought: you have one day left for submission)

Dr Shock of the blog with the same name advises us to submit good quality, easy-to-understand posts dealing with science, environment or medicine to Scientia Pro Publica via the blog carnival submission form.

There is a new on-line science blogging community – Scientopia, till now mostly consisting of bloggers who left Scienceblogs after (but not because of) Pepsigate. New members can only be added to the collective by invitation (?). Obviously, pepsi-researchers will not be invited, but it remains to be seen who will…  Hopefully it doesn’t become an elitist club.
Virginia Heffernan (NY-Times) has an outspoken opinion about the (ex-) sciencebloggers, illustrated by this one-liner

“ScienceBlogs has become Fox News for the religion-baiting, peak-oil crowd.”

Although I don’t appreciate the ranting-style of some of the blogs myself (the sub-“South Park” blasphemy style of PZ Myers, as Virginia puts it). I don’t think most Scienceblogs deserve to be labelled as “preoccupied with trivia, name-calling and saber rattling”.
See balanced responses at: NeurodojoNeuron Culture & Neuroanthropology (anything with neuro– makes sense, I guess).
Want to understand more about ScienceBlogs and why it was such a terrific community, then read Bora Z’s (rather long) ScienceBlog farewell post.

Oh.. and there is yet another new science blogging platform: http://www.labspaces.net/, that has evolved from a science news aggregator . It looks slick.

Social Media

Speaking about Twitter, did you know that  Twitter reached its 20 billionth tweet over the weekend, a milestone that came just a few months after hitting the 10 billion tweet mark!? (read more in the Guardian)

Well and if you have no idea WHAT THE FUCK IS MY SOCIAL MEDIA “STRATEGY”? you might click the link to get some (new) ideas. You probably need to refresh the site a couple of times to find the right answer.

First-year medical school and master’s of medicine students of Stanford University will receive an i-pad at the start of the year. The extremely tech-savvy Students do appreciate the gift:

“Especially in medicine, we’re using so many different resources, including all the syllabuses and slides. I’m able to pull them up and search them whenever I need to. It’s a fantastic idea.”

Good news for Facebook friends: VoIP giant Vonage has just introduced a new iPhone, iPod touch and Android app that allows users to call their Facebook friends for free (Mashable).

It was a shock – or wasn’t it – that Google pulled the plug on Google Wave (RRW), after being available to the general public for only 78 days?  The unparalleled tool that “could change the web”, but was too complex to be understood. Here are some thoughts why Google wave failed.  Since much of the Code is open source, ambitious developers may pick up where Google left.

Votes down for the social media site Digg.com: an undercover investigation has exposed that a group of influential conservative members were involved in censorship, deliberately trying to ban progressives, by “burying them” (voting down), which effectively means these progressives don’t get enough “digs” to reach the front page where most users spend their time.

Votes up for Healthcare Social Media Europe (#HCSMEU), which just celebrated its first birthday.

Miscellanous

A very strange move: a journal has changed a previously stated conclusion of a previously published paper after a Reuters Health story about serious shortcomings in the report. Read more about it at Gary Schwitzer’s HealthNewsReview Blog.

Finally for the EBM-addicts among us: The Center of Evidence Based Medicine released a new (downloadable) Levels of Evidence Table. At the CEBM-blog they stress that hierarchies of evidence have been somewhat inflexibly used, but are essentially a heuristic, or short-cut to finding the likely best evidence. At first sight the new Table looks simpler, and more easy to use.

Are you a Twitter user? Tweet this!





Stories [5] – Polly Matzinger, the Bunny & the Dog

22 03 2010

Stories is a new series that tells a selection of my personal stories, mostly from the time I was a student or worked as a scientist.
I wrote the draft of this post a year ago. The theme of the Grand Round hosted by Ramona Bates at Suture for a Living
posts that have to do with women in medicine as patients, as providers, as scientists” prompted me to take up the thread.

The present story took place at my first job as a scientist in the early eighties. I worked with Pavol Ivanyi, a well known immunologist, specialized in inbred mice strains and the MHC (Major Histocompatibility Complex, i.e. major transplantation antigens). Once a week we held a sort of Journal Club, that took place in our office, a small and dark room without any windows. There was a table, a blackboard and our desks. Pavol often wore the same brown woolen sweater. We had no computers, not to mention powerpoint presentations. We just had a flip-over and a blackboard.

Once it was my turn. The paper I discussed was written by P. Matzinger as first author and if I remember it well R. Zamoyska.

Little was known at that time about how the immune response reacted to foreign material but not to “self”. The MHC plays a major role in this and P Matzinger had  truly original ideas about how this worked.
I guess I must have been nervous, because it was quite a difficult theoretical paper (for me at that time).

Many times I said: “he thinks, he had the bright idea, he proposes, he concludes…”.

After I finished my presentation, Pavol took a deep breath and said frowning:

“…..It is not a HE.”

I gazed with a kind of wonder. He continued with his typical Czech accent, serious but with a twinkle in his eyes.

“It is a SHE” …….

“It is a she and …. a very beautiful one”

Then he told us that Polly Matzinger, for that was her name, was once a Playboy bunny and a waitress at a bar frequented by scientists. A well known professor noticed her talent and persuaded her to become a scientist and get her PhD.
She appeared to be a very original, but also controversial lady. Pavol knew her well.

Pavol carried on:

“Polly has written a paper together with Galadriel Mirkwood* (see pdf here). Do you know who that is?

I nodded: “No” (how should I know?). The name Galadriel, one of the elves of  Lord of the Rings, might have been a hint.

“Mirkwood is her Afghan Hound, it is a dog, She found that her dog was as much involved in research as many other coauthors.”

727px-polly__annie1

According to Ted Anton’s book Bold Science, the dog was put on as a coauthor for this Journal of Experimental Medicine paper [1], because  she refused to write in the usual scientific passive voice (‘steps were taken’) but was too insecure to write in the first person (‘I took the steps’). Once discovered, papers on which she was a major author were then barred from the journal until the editor died and was replaced by another (see Wikipedia).

But as a matter of fact, one of her main ideas originated from observing her sheepdog (she is a sheepdog expert as well, and a jazz musician, carpenter, lab technician and problem-dog trainer). “I suddenly realized that there was a cell in the body which behaves like a good sheepdog – the dendritic cell. The dendritic cell would be activated by a cell dying in its midst and kickstart the immune response. And that puts the model together”. (The Independent)

Polly Matzinger is famous for her Danger Model, published in many prominent journals, like Science,  Ann N Y Acad Sci, J Immunol, Transplant Proc, Nature Med, Nature Immunology (see refs).

The BBC even made a Horizon -edition about her and her ideas. Horizon, as you may know, is a current and long-running BBC popular science and philosophy documentary program. She does now how to stand out, although sometimes this desire to stand out can overshadow her skills as a scientist and presenter according to some.

Her Danger theory challenges core beliefs about how our immune system works.

The paradigm developed by Janeway (and the Nobel Price winners Medawar/Burnet) is that non-self (foreign) triggers an immune response, while self does not. According to Polly the “self/non-self” model is not adequate.

A system that attacked everything foreign would lead to the system attacking the food we eat; a mother’s body would reject the foetus it carried. Instead, Matzinger thinks, what the body (and notably the dendritic cells) notices is danger.

This is how she explains her danger theorie in the New York Times (1998):

Q. How does your Danger Model differ from the standard Self/Nonself Model of the immune system?

A. It isn’t really insurrectionary — it’s just a different way of looking at things. Let me use an analogy to explain it. Imagine a community in which the police accept anyone they met during elementary school and kill any new migrant. That’s the Self/Nonself Model.

In the Danger Model, tourists and immigrants are accepted, until they start breaking windows. Only then, do the police move to eliminate them. In fact, it doesn’t matter if the window breaker is a foreigner or a member of the community. That kind of behavior is considered unacceptable, and the destructive individual is removed.

The community police are the white blood cells of the immune system. The Self/Nonself Model says that they kill anything that enters the body after an early training period in which ”self” is learned.

In the Danger Model, the police wander around, waiting for an alarm signaling that something is doing damage. If an immigrant enters without doing damage, the white cells simply continue to wander, and after a while, the harmless immigrant becomes part of the community.

She emphasize for instance that tumors are often not seen as dangerous and therefore not attacked by the immune system, until they outgrow their blood supply, undergo chemotherapy, or otherwise are harmed. Then the damaged tumor cells release endogenous danger signals that help trigger the adaptive response. (see this excellent blog post at Mystery Rays from Outer Space for more detailed discussion).

Her theory also implies that transplants could be permanently accepted if the danger signals could be blocked at the time of the transplant with a short course of drugs. Indeed some of her experiments point that way.

Others insist that it is not much different from the original theory, if one implies the need of a second signal (danger-signals, besides the recognition of non-self).

However, whether she is right or wrong doesn’t really matter in the long run.

Indeed like she said in the NY times:

“It is said the scientist who is willing to stick his neck out and be clear will contribute to the field whether he or she is wrong or not, because if they are wrong someone will do the experiments to prove they’re wrong and in the process will learn something about nature. So whether I’m right or wrong doesn’t matter.”

Her truly original ideas have stimulated the progress of science. She is an outstanding scientist. According to her own definition science is ” about describing nature, and so is art: We’re painting nature.(…) Actually, it’s a sandbox and scientists get to play all of our lives.

She is a scientist who is changing our world.

References

  1. Matzinger, P. and Mirkwood, G. (1978). In a fully H-2 incompatible chimera, T cells of donor origin can respond to minor histocompatibility antigens in association with either donor or host H-2 type. Journal of Experimental Medicine, 148, 84-92.
  2. Ted Anton. Bold Science: Seven Scientists Who Are Changing Our World (Paperback) 193 pages; Publisher: W. H. Freeman (May 1, 2001) ISBN-10: 0716744481 ;ISBN-13: 978-0716744481
  3. Matzinger P. The danger model: a renewed sense of self. Science. 2002 Apr 12;296(5566):301-5.
  4. Matzinger P. An innate sense of danger. Ann N Y Acad Sci. 2002 Jun;961:341-2. Review. No abstract available.
  5. Alpan O, Rudomen G, Matzinger P. The role of dendritic cells, B cells, and M cells in gut-oriented immune responses. J Immunol. 2001 Apr 15;166(8):4843-52.
  6. Celli S, Matzinger P. Liver transplants induce deletion of liver-specific T cells. Transplant Proc. 2001 Feb-Mar;33(1-2):102-3. No abstract available.
  7. Guimond M, Veenstra RG, Grindler DJ, Zhang H, Cui Y, Murphy RD, Kim SY, Na R, Hennighausen L, Kurtulus S, Erman B, Interleukin 7 signaling in dendritic cells regulates the homeostatic proliferation and niche size of CD4+ T cells. Nat Immunol. 2009 Feb;10(2):149-57. Epub 2009 Jan 11.




Information is Beautiful. Visualizing the Evidence for Health Supplements.

21 03 2010

In a world driven by data, we need a simple means of digesting it all. Visualization of data may help to coop with the information overload. Good visualizations enable people to look at vast quantities of data quickly.

Bram Hengeveld at Geriatric Care (geriatricare.wordpress.com) told me of Snake Oil, a fantastic visualization of scientific evidence for popular health supplements. A well chosen name too, because Snake oil  is both a traditional Chinese medicine, as a  term for “medicines” that are fake, fraudulent, quackish, or ineffective. The expression is also applied metaphorically to any product with exaggerated marketing but questionable or unverifiable quality or benefit. (Wikipedia).

Snake oil is just one visualization at Information is Beautiful (link), the site created by David McCandless, a London-based author, writer and designer who wrote for The Guardian, Wired and others, and nowadays an independent data journalist and information designer. His passion: visualizing information – facts, data, ideas, subjects, issues, statistics, questions – all with the minimum of words (see about).

When you see snake oil you intuitively understand it all.

The image is a “balloon race”. The larger the bubble the higher its popularity in terms of number of Google hits. Orange bubbles look promising but have (yet) a low evidence.

The higher a bubble, the greater the evidence for its effectiveness. But the supplements are only effective for the conditions listed inside the bubble. Evidence is only shown for supplements, taken orally by an adult with a healthy diet.

Some supplements may be represented by multiple bubbles, one for each condition:  after all, the evidence may vary across conditions. For example, there’s strong evidence that Green Tea is good for cholesterol levels. But evidence for its anti-cancer effects is conflicting.

Another nice thing about Snake oil is that it is interactive. You can show (filter) the results for specific conditions or supplement types. Below I selected cardio. Most bubbles disappear. The evidence seems strong for green tea, fish oil and red yeast rice and low for vitamin E and omega-3. When you move your mouse over a bubble it pops up and you can read the supplements name and the condition to which the evidence applies.

Truly amazing.

One might ask how GOOD are the data on which these bubbles are based?

Well I haven’t checked, but the visualization generates itself from this Google Doc. The Google spread sheet shows all the data on which the visualization is based. These can be PubMed Records, Cochrane Systematic Reviews, Medline Plus or a full text paper. The image is automatically regenerated when the google doc is updated with new research that has come out.

The only thing that strikes me as a information specialists is that the way the evidence is retrieved is not stated. Probably this isn’t done in an evidence based way, because each piece of evidence is based on ONE article only. The choice of the paper seems rather random. And some supplements are rather vague. What is meant with “anti-oxidants?” Many of the supplements have anti-oxidant activity for instance.

But the idea in itself is great. Suppose we could gather the evidence in a more evidence based way, share it in Google Docs, appraise it and visualize it. Wouldn’t that be wonderful?





Friday Foolery #14: Pronouncing Hoechst

4 12 2009

Ever had that? You ‘re giving a scientific lecture and you mispronounce one or a few words. Sometimes you know a word is hard to pronounce, but, knowing that, it even gets harder to pronounce the word correctly. For instance, I find it hard to pronounce certain gynecological and dermatological diseases.

Sometimes you don’t know that you mispronounce certain words. Perhaps because you never spoke the words out loud, just read the text. These words need not be very exotic.

Once it was my turn to lead the journal club at the genetics department. Afterwards the Professor, Gert Jan van Ommen, came to me and said: “It was a nice talk, but please never say “mature” in the way you say “nature” again!

Foreign firm names may also be hard to pronounce. The following video from Benchfly illustrates that.

Vodpod videos no longer available.

Hattip: @nutrigenomics on Twitter (see tweet)

Benchfly is a resource, initiated by the chemist Alan Marnett in 2009, dedicated to providing researchers with current protocols to support their lives both in and out of the lab. For instance by instructive videos.

One such video protocol is “how to send DNA”. Ingenious, but I wonder if it is legally permitted to send it abroad (customs). But who ever tried to send DNA samples styrofoam box hunts via FedEx will welcome this tip. Pity it doesn’t work with cell cultures….

Vodpod videos no longer available.

By the way David Rothman pointed at the pronunciation guide Forvo (http://forvo.com/): all the words in the world pronounced by native speakers.

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Friday Foolery #13: A Virus Walks into a Bar

27 11 2009

For Friday Foolery a picked up this fragment from the science comedian Brian Malow. He performed in the session Science Laughs at Wonderfest 2009, The San Francisco Bay Area Festival of Science. The complete video can be viewed at Fora.tv (2009/11/08).

I like the virus/bacteria part, but it took a while for me to understand that ‘staff’ should be spelled as ‘staph’.

Hattip: Betabieb on Twitter (Edwin Mijnsbergen)

Voor Nederlanders. Betabieb heeft ook een site: http://www.betafactor.nl/: internet- en bibliotheekbronnen op bètagebied.

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Hot News: Curry, Curcumin, Cancer & Cure

3 11 2009

347513745_54fd37f269 curcuma curry

*Hot* News via Twitter and various news media a few days ago. Big headlines tell the following in respectively The Sun, Herald, Ireland, BBC News / NHS Health and Reuters:

Curry is a ‘cure for cancer

Spices in curry may help cure cancer

Curry spicekills cancer cells

Scientists say curry compound kills cancer cells

The message of these headlines is quite different and so are the articles themselves (covered more in depth by @jdc325 at the BadScience Blog “Stuff and Nonsense” (see here)). They vary from “curry being a cure for cancer” to “a possible effect of one of its compounds on cancer cells”.

So what was (not) done?

  1. Cancer was not cured.
  2. It was not a human trial.
  3. The study didn’t test effects on living laboratory animals, like mice, either.
  4. The study was done in the test tube, using individual cancer cell lines.
  5. The cells tested were (only) esophageal cancer cell lines.
  6. Testing the drugs efficacy was not the main aim of the study.
  7. Curry (a complex spicy mixture) wasn’t used.
  8. Curcumin was tested, which makes up 3% of “turmeric”, that is one of the spices in curry.
  9. That curcumin has some anti-carcinogenic effects is not new (see my tweet linking to 1120 hits in PubMed with a  simple PubMed search for curcumin and cancer: http://bit.ly/3Qydc6)

So why the fuss? This doesn’t seem to be a terribly shocking study. Why the media picked this one up is unclear. It must have been, because they were sleeping (missed all the previous studies on curcumin) and/or because they are fond of these kind of studies: except from the experimental details- these studies translate so well to the general public: food – cure – cancer.

And the headlines do it much better than the actual title of the article:

Curcumin induces apoptosis-independent death in oesophageal cancer cells

I experienced the same when my study was picked up at a cancer conference by BBC-health, whereas other far more pioneering studies were not: these were harder to grasp and to explain ‘to the public’ and without any possible direct health benefit.

What was already known about curcumin and cancer? What was done in the present study? What is new? And is curcumin really a promising agent?

Already known.

Curcumin (diferuloylmethane) is a polyphenol derived from the plant Curcuma longa, commonly called turmeric. It gives the curry it bright yellow color. Curcumin has a plethora of beneficial effects in vitro (in the test tube) and in animal studies, including anti-microbial,  anti-arthritic and  anti-inflammatory effects, but most interesting is its anti-carcinogenic effect. It has potential for both prevention and therapy of cancer, but the evidence for preventive effects is most convincing. The mechanisms playing a role in the anticarcinogenic effect are also multifold and complex. Possible mechanisms include: Inhibition/protection from DNA damage/alterations, Inhibition of angiogenesis, Inhibition of invasion/metastasis, Induction of apoptosis, Antioxidant activity, Induction of GST, Inhibition of cytochromes P450, I NF-jB, AP-1, MMPs, COX-2, TNF-a, IL-6, iNOS, IL-1b, the oncogens ras/fos/jun/myc, MAPK, ornithine decarboxylase, Activation of Nrf2, Induction of HO-1, Activation of PPAR-c  and Immunostimulant/immunorestorer effect……….[2]

New Findings

This is to put in perspective that the researchers found yet another possible mechanism (although others have found evidence before, see introduction [1]). Using a small panel of esophagus cancer cells, they first showed that the cells were selectively killed by curcumin. Next they showed that the major mechanism wasn’t apoptosis, cell death by suicide, but cell death by a mechanism called “Mitotic catastrophe”, a type of cell death that occurs during mitosis (cell division) (see free review in Oncogene [3]). As with apoptosis many steps have to go wrong before the cell will undergo mitotic catastrophe. The researchers show that curcumin-responsive cells were found to accumulate poly-ubiquitinated proteins and cyclin B, consistent with a disturbance of the ubiquitin–proteasome system: ubiquitin labels proteins for degradation by proteasomes, thereby controlling the stability, function, and intracellular localization of a wide variety of proteins.

In other words, this study is mainly about the mechanisms behind the anti-cancer effects of curcumin.

Cure?

Of course this paper itself has no direct relevance to the management of human esophagus cancer. The sentence that may have triggered the media is:

“Curcumin can induce cell death by a mechanism that is not reliant on apoptosis induction, and thus represents a promising anticancer agent for prevention and treatment of esophageal cancer.”

Which is of course to far-fetched. The authors refer to the fact that esophageal cancers are often resistant to cell death induction with chemotherapeutic drugs, but this only indirectly points at a possible role for curcumin.

It has to be stressed that no human study has convincingly shown an anti-tumor effects of curcumin. Studies that have been done are observational, i.e. show that people taking higher concentrations of curcumin in their diet have a lower incidence of several common cancer types. However, such studies are prone to bias: several other factors (alone or in together) can be responsible for a anti-cancer effect (see previous post [5] explaining this for other nutrients).

The Current grade of evidence for a preventive or therapeutic effect is C, which means “unclear scientific evidence” (see MedlinePlus).

Although there are several trials under way there is reason to be skeptical about the potential of curcumin as cancertherapeutic agent.

  • The limited bioavailability and extensive metabolism of curcumin suggest that many of its anticancer effects observed in vitro may not be attainable in vivo. On the other the gastro-intestinal system is he most likely place for an effect of curcimin taken by the oral route. [2]
  • Although relatively high concentrations of curcumin have not shown significant toxicity in short-term studies, these concentrations may lead to toxic and carcinogenic effects in the long term.[2]
  • The therapeutic effects are dose-dependent. As often seen with these bioactive compounds, toxic effects can occur at supra-optimal amounts. Indeed curcumin has shown to be toxic and carcinogenic under specific conditions. At low and high doses curcumin behaves as an anti-oxidant and a pro-oxidant (toxic) respectively. [2, 6 ]
  • Often more ingredients add to the therapeutic effect, or more foods/habits [5].
  • The FDA has a shortlist of “187 Fake Cancer “Cures” Consumers Should Avoid”, compounds containing curcumin are on that list [7].

Conclusion

So, concluding, a study that unraveled one of the mechanisms whereby curcumin can kill cancer cells, led to an exaggerated and sometimes completely wrong coverage in the media. Why this was done is unclear, but the ultimate result of such misplaced drumroll will only lead to disbelief or carelessness.

Shame on you, media!!ResearchBlogging.org

Photo credits

http://www.flickr.com/photos/trentstrohm/347513745/

References

  1. O’Sullivan-Coyne, G., O’Sullivan, G., O’Donovan, T., Piwocka, K., & McKenna, S. (2009). Curcumin induces apoptosis-independent death in oesophageal cancer cells British Journal of Cancer, 101 (9), 1585-1595 DOI: 10.1038/sj.bjc.6605308
  2. López-Lázaro, M. (2008). Anticancer and carcinogenic properties of curcumin: Considerations for its clinical development as a cancer chemopreventive and chemotherapeutic agent Molecular Nutrition & Food Research DOI: 10.1002/mnfr.200700238
  3. Castedo, M., Perfettini, J., Roumier, T., Andreau, K., Medema, R., & Kroemer, G. (2004). Cell death by mitotic catastrophe: a molecular definition Oncogene, 23 (16), 2825-2837 DOI: 10.1038/sj.onc.1207528
  4. Stuff and Nonsense – Curry can cure cancer, say scientists (2009/10/28)
  5. The best study design for dummies (2008/08/25)
  6. Huge disappointment: Selenium and Vitamin E fail to Prevent Prostate Cancer.(post on this blog about the SELECT trial – 2008/11/16)
  7. http://www.fda.gov/Drugs/GuidanceComplianceRegulatoryInformation/EnforcementActivitiesbyFDA/ucm171057.htm

You may also want to read:

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Peter Palese on H1N1/Influenza, Porcine and Otherwise

9 09 2009

Vodpod videos no longer available.

Seen on MicrobeWorld, posted by Chris Condayan: a video in which Peter Palese, Professor and Chairman of the Department of Microbiology and Infectious Diseases at Mt. Sinai, explains H1N1/swine flu, the natural herd immunity that all humans share against it, and the reasons why the elderly stand at a lesser risk of contracting the virus.

Found the video interesting? There are a lot more interesting posts, images and video’s on MicrobeWorld to read or watch.

Established in 2003, MicrobeWorld is an interactive multimedia educational outreach initiative from the American Society for Microbiology, a non-profit organization that “promotes awareness and understanding of key microbiological issues to adult and youth audiences, and showcases the significance of microbes in our lives.”

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