MicrobeWorld App


Microbes After Hours

Click for "Microbes After Hours" videos

Featured Image

Featured Video


New from ASM Press


Join MicrobeWorld


ASM House 200X200

Subscribe via Email


TWiV 174 Letters

Mark writes:

Hi TWIVers,

I love your podcast! I am a postdoc in Joe DeRisi's lab at UCSF and I know that right now I am supposed to be aiming for a faculty job. But my real goal is to discover something cool enough to end up on TWIV.

Anyway, the main reason I'm writing is to suggest this pick of the week: a fascinating Fresh Air interview with Craig Timberg, the author of Tinderbox, a history of the HIV/AIDS pandemic.


MP3: http://pd.npr.org/anon.npr-mp3/npr/fa/2012/02/20120227_fa_01.mp3

Thanks for TWIV - it is really a very good thing.



Postdoc, DeRisi lab, UCSF

Henry writes:

Twiv Team (T^2),

This one is primarily for Rich since he suggested Battlestar Galactica. I lost a week of productivity with that one. Thanks a lot :)


I watched the first season while I was in Iraq as a medic. It is pretty good biomedical sci-fi, though the language and content make it for adults over a general audience.

I do not have any questions at this time. I have listened consistently ever since I joined a virology/biochemistry lab for my PhD work. Thanks again for the great show.



Ian writes:

Re: Alan's query of rectal swabbing in the 'A distinct lineage of influenza A virus from bats' paper...

Wouldn't the rectal swabs have had more to do with looking for the possibility of transmission of a virus via the guano, with human exposure to the guano (...being collected for use as a crop fertilizer...) being the theoretical infection route?

Jason writes:

Hey TWiV crew,

I took the opportunity to donate blood today and noticed that in addition to the normal information about HIV, Hepatitis, NAT, etc. testing, there was a page an a half of information about XMRV and CFS. I pointed out that the information they provide has effectively been debunked to the first screener, who effectively dismissed my comments. I think they were volunteers and not really medical professionals, so that response seems normal. When I was then screened by an RN, I mentioned the problem again. She seemed taken aback that I would claim their pamphlet was incorrect, and then effectively dismissed my claim.

In looking over the pamphlet now, I notice that it's the 2008 revision, so I suppose the data on there is accurate for about that timeframe, but I find it somewhat irresponsible to continue spreading incorrect information so many years later.

I do find one of these questions somewhat amusing. They ask whether a person diagnosed with CFS should be donating blood. The answer they provide is that while the person donating should be in good health, it's up to the medical directors at the blood collection centers to decide whether or not people diagnosed with a history of CFS should donate or not. With all of the precautions prohibiting donations from people who have been in contact with others who are diagnosed with illnesses like hepatitis or HIV, I find it hard to believe that they leave it up to the medical director to make the call on CFS.

At any rate, keep up the interesting podcast. Despite not being in the field, I find it stimulating and I'm learning a lot. Or, at least, learning enough to cause trouble... ;)

Jason 'XenoPhage'

Roger Dodd, VP for R&D, American Red Cross replies:

Thanks for asking. This is an interesting commentary. My first comment would be that, while most aspects of blood collection are highly standardized, different organizations may have differing approaches to certain issues that are not defined by regulation or voluntary standards. Certainly, management of CFS and XMRV would fall into this particular category. AABB, the professional organization for transfusion medicine did issue some guidance to its members in 2010, recommending that blood collectors "educate" donors and ask them to refrain from donation if they had a medical diagnosis of CFS and providing website information for CFIDS. Interestingly (and to my mind appropriately) XMRV was not explicitly mentioned. For some blood collectors (the Red Cross is one), this procedure is still in place: Red Cross materials, however, do not mention XMRV. However, the task force that originally made the recommendation has advised AABB that its members should revert to whatever practice was in place prior to the recommendation. It is possible that the educational document was handed out along with other materials dated 2008: I doubt that any blood organization in the US had any explicit materials about CFS in 2008 and they would definitely not have cited XMRV then.

Blood collection staff are supposed to be knowledgeable about the materials that they distribute, but they are engrained in a highly disciplined and strongly regulated environment. If they have not been retrained, it is quite possible that they would adhere to prior requirements. Unfortunately, it is also possible that that they would not be particularly knowledgeable about the medical and scientific issues at hand.

Finally, in areas of medical uncertainly, it does fall to the medical director to make final decisions about donor eligibility. The overriding criterion is that the donor should be healthy and feeling well at the time of donation.

Your correspondent has asked astute questions - I hope you can make sense of my responses.

Please do not hesitate to get back t me if more is needed. If you would prefer the one-word answer, it is "inertia"!



Keith writes:

Dear Twividae,

My name is Keith and I am with the HIV Reference Laboratory here in the Bahamas and would like to know if you have heard are any online PhD programs where the thesis can be completed at ones own lab. If any of you are ever in the Bahamas send me an email, I can show you around.

Thanks, Keith

Benjamin writes:

Howdy “Hosts”

I’m one of those three highschool geeks who listens to TWiV TWiP and TWiM. I’m sixteen, and while some of the subjects (Like the molecular bio of zinc finger) are above me, your science is down-to-earth and understandable.

I’ve been latently infected since late 2010 since TWiP and TWiM had fewer episodes to get a catchup hold on. A couple of weeks ago, however, it became a full blown clinical infection and got the world’s biggest TWiV fix. What a powerhouse, you guys. Now, thanks to TWiV, I’ve fallen behind in my other podcasts.

I’ve had an unofficial game going with Alan since TWiV 20 to see if I can come up with any bad virus puns that he missed. So far, I’ve only gotten one. In TWiV 58 - Nipah virus in ferrets, the scientists doing the experiments were ferreting out the mode of infection. It’s no secret that I have a droll sense of humor, so maybe other listeners can go through the TWiV backlog to find more.

I would like to offer my take on the aliveness of viruses. Every time you argue the point of viruses, you bring up the prions and transposons. Transposons are not alive since they are genes already in the genome rearranging themselves spontaneously and stochastically as far as I can tell. Thus, they are mutations, not organisms. Prions are misfolded proteins. CJD (Creutzfeldt-Jakob disease) and kuru are basically the protein affecting the tissue and misfolding more proteins. The damage could probably be replicated by injecting pepsin, tripsin, and demyelination factors, which are also proteins, and thus, prions are also not alive. Then, we come to viruses. Viruses are beautifully designed to do what they do best. The characteristics of life list (Bio 221, Earl Beyer--iTunes U--Talaro’s 7th edition of foundations of microbiology) are many, but several include: reproduction (check) a genome (check) and a “cell” barrier (check) by this reasoning, viruses are alive despite a marked lack of things like irritability, (that means response to the environment) metabolism, cellular design et al.

I think I tipped my politico-religious hand in the previous paragraph, but that needs tending to as well. I can’t imagine that me and one of my friends that I hooked on TWiV are the only Christians (shall I say, non-evolutionists?) getting our TWiV fix every Monday morning, so in the future could you please think twice before shamelessly trashing religion?

In TWiV 150, Rich talked about Buda, TX. I happen to have lived close to there (by Texas’ standards…it’s about a hundred miles) for all my sixteen years and have never heard it called anything but BOO-duh.

I’ve written you on TWiP before about a syndrome that I called “Stumbling Poultry Disease” maybe with all the resources of TWiV we can get an answer. DESCRIPTION: It only happens in the summer when the local temperatures soar as high as 115º F in the shade, (I’ll take up Rich on the challenge that no one but a Floridan could survive the Florida climate) superheating the waterers to well above the required 90º F for E polyphaga despite our best efforts. Add that to the fact that chickens and turkeys are sloppy drinkers, (meaning that water runs into their noses) and wallah! We have poultry displaying weird behavior followed by disorientation, stumbling, vertigo-like symptoms and eventually death. Perhaps Alan with his insta-google or Rich with firsthand experience with the southern climate can add some ideas to the pool.

That’s about it for now, love the podcast, hoping for TWiB and TWiF. Live long and podcast,

Greetings from south-central Texas, the summer residence of the golden-cheeked warbler. (cue impromptu ecology lecture by Dick)

Jon writes:

Dear Vincent, Dick, Rich, Alan and the TWIV gang,

I found the recent experimental use of viruses which can only reproduce in cancer cells (reported in TWIV 156 and 131) as anticancer agents to be exciting news. I wonder if it is possible to use natural selection to produce viruses (or for that matter immune-system evading parasites) with improved cancer-killing properties, alleviating the need for rational drug design.



Rick writes:

Hi Vincent, Rich, Alan and Dickson.

I'm a software engineer at Google with a bit of education in genetics and computational biology. I've been listening to TWiV and really enjoying it for a couple years now, but it makes me really curious to better understand the patterns of infection in my own home. It drives me nuts that we can understand so much about viruses in general, but when I get a cold I don't know what virus and strain it is or where I likely contracted it from. I can imagine a future where it's routine and virtually free to sequence someone's virome whenever they are sick - imagine what we could do with all that data!

So I want to try to learn more about the patterns of infection in my home (eg. what viruses do we get, do my kids tend to get viruses from me or vice versa, etc.). I've been reading a number of papers and searching for services/tools I could use but it's tricky to get a good picture about what techniques would really be practical (and safe) to do myself from home. Perhaps the ideal approach would be to find a lab that would do multiplexed RT-PCR on nasopharyngeal samples I send them, giving me the viral load for the most common URT viruses. Maybe I could also do a little home DNA purification and send it out for sequencing when I wanted to know more about the precise strain. The simplest approach looks like it would be to order some ELISA kits, but it would be nice to have the sensitivity and quantified result of PCR so I can track viral load over the course of an infection. I'm willing to invest a bit in lab equipment and services, but would ultimately like to find something scalable and cost effective. Is there anything you can suggest?

Along these lines, here's a potential pick-of-the-week for you: BioPunk: DIY Scientists Hack the Software of Life. I like how this book relates the current state of biology to the early years of computing, and suggests what might be possible if biology gets the equivalent of the open source movement and personal computers.

Thanks, keep up all the great work on TWi*!

Liam writes:

Hello twivers,

Have you seen this?



Comments (0)

Collections (0)

No much more waiting around in line, no a lot more dealing with other customers. Purchasing requires. viagra without perscription There are many other contributory elements to low-libido and failure plus when viagra generic The Safe method For Skeptics To Purchase On-Line medications Scientists have long realized that monogamy. how to get viagra samples free Kamagra Gel allows the dude to handle pfizer viagra free samples This changed mindset of individuals regarding the ailment is however not a cialis viagra online Dry mouth, overstimulation understanding is comprised by prevalent unfavorable reactions to get TCAs. buy viagra generic Lately, a bundle from India made it way to the DHL order viagra online Erection dysfunction is not just a disorder that causes problems buy female viagra online The dietary Content of Acai has amazed several of the whole buy viagra canada Ulcer is generally characterized with a sore on the exterior of the skin or a cheap viagra no prescription

American Society for Microbiology
2012 1752 N Street, N.W. • Washington, DC 20036-2904 • (202) 737-3600
American Society For Microbiology © 2014   |   Privacy Policy   |   Terms of Use