Jacob writes:

Hi TWiV hosts (and Vincent’s wife),

I heard Vincent lament on TWiV 481 that it was not possible yet to repair cartilage with stem cells and I wanted to draw your attention to a Sydney based Biotech company that is doing exactly that.

Regeneus (www.regeneus.com.au) have a treatment using adipose-derived mesenchymal stem cells injected into the knee to improve cartilage volume and reduce knee pain which has been widely used in veterinary medicine and has completed Stage 1 clinical trials in humans.

The Stage 2 clinical trials are running in Japan, so if Vincent and his wife want to take another trip to Japan (outside of Cherry Blossom season, obviously).

Also, I noticed today that Vincent’s Wikipedia page is kinda short. Can the TWiV army help him out?



Johnye writes:

PLEASE don’t give up Picks. You, and many listeners, have provided fascinating, beautiful, inspiring and (legal) mind-expanding trips to unknown wonders in world that surround us. Your collective, and individual, knowledge and passion for the sweet mysteries of life, as you must know, is infectious and highly contagious! It’s in the community now; can’t put it back in the test tube.


April writes:

OK ironically you guys miss-pronounced Gonzaga, the university. The correct pronunciation of the first a is with a long a. I live in Spokane.

I’m a botanist and my favorite beginner botany book is called Botany in a Day: The Pattern Method of Plant Identification by Thomas J. Elpel.

Lucian writes:

Dear TWiV masters,

I was listening to episode 479 when Dickson explained Bt’s mechanism of action. However, from what I understand, Bt is insect-specific because they often have alkaline midguts. Under alkaline conditions, the protein decrystallizes, solubilizing into an active pore-forming toxin that lyses the gut. Bt’s activity under high pH is what renders it safe for human consumption: our acidic stomach denatures and destroys the toxin in its inactive state.

From “Mode of action if Bacillus thuringiensis Cry and Cyt toxins and their potential for insect control”:

“Cry proteins pass from crystal inclusion protoxins into membrane-inserted oligomers that cause ion leakage and cell lysis. The crystal inclusions ingested by susceptible larvae dissolve in the alkaline environment of the gut, and the solubilized inactive protoxins are cleaved by midgut proteases yielding 60–70 kDa protease resistant proteins.”

Bravo, Gill, and Soberón, “Mode of action if Bacillus thuringiensis Cry and Cyt toxins and their potential for insect control” Toxicon. 2007 Mar 15; 49(4): 423–435. doi:  10.1016/j.toxicon.2006.11.022

As always, an excellent podcast! Thank you all for all the work you do!


Lucian DiPeso

Roton at the Hatch Lab

University of Washington

Molecular & Cell Biology

Brady writes:

Hi TWIV crew,

As an avid listener to your podcast, I have been wanting to write for a long time!!

I am a Ph.D. student at Utah State University studying the molecular mechanisms rendering a species susceptible to New World arenavirus infection.

I often listen to TWIV as I exercise to relieve the stress of graduate school. While I enjoy doing this, other patrons of the gym probably find it a little weird when I start laughing at the jokes and puns that frequent the episodes!!

Anyways, I had the chance to meet Drs. Racaniello and Despommier last summer at the arbovirus conference at RML in Montana. As I sat in the first row during the podcast, it was very interesting to see an actual recording of the podcast occur.

Also, I hope the fishing trip went well while you guys were up there. As an avid fisherman myself, nothing is better than getting out on the river and seeing the fish bite.

Thank you for the good work on this podcast and I look forward to the next episode!!


Anthony writes:

Scott writes:

Hello TWIV Team,

I hope I’m not too late to enter the book contest, I have been honing my skills on CD4 Hunter and have finally reached a score I think could be competitive. I would be interested to hear how other people did, this game gets difficult very quickly.

[he got 9430!]

I also have a few questions regarding the glycosylation site mutation in H3N2, specifically that if this mutation sits on the head of the hemagglutinin protein, wouldn’t this be a disadvantage to binding of sialic acid? If so, I would assume the selective advantage would be for the decrease in host immune response at the cost of binding proficiency, but overall infectivity goes up because of the lack of antibody inhibition. I don’t really know enough about sialic acid, but are the sialic-acid chains that are found in the lungs of the same configuration as those found elsewhere in the body? I remember (perhaps incorrectly) a paper discussed on TWIV that looked at the 1918 flu and documented the virus’s increased affinity for infecting cells in the lower lungs when compared to more modern strains, which they attributed to increased virulence. Avian Influenza seems to have a configuration specificity, which I guess is why it hasn’t killed us all, yet. To get to the point, this lack of antibody affinity for a virus made me think of Dengue Virus and the antibody dependent enhancement. Is it possible that influenza, normally fairly contained in the lungs, is now able to infect other cell types through the Fc receptor and create a different disease state from the non-glycosylated H3N2?

I apologize for the long email, it took me a while to get to my real question. As always thanks for all that you do.


PS: Personally I love the length, weather, picks, jokes, etc that makes TWIV so great. I wouldn’t presume that my opinion can sway the show in one way or another, but if the wonderful hosts of TWIV get enjoyment from the show, and obviously you give enjoyment to all of us listeners, then don’t change a damn thing.

Steffen writes:


I just discovered your podcast. I really like podcasts and also virology so it‘s a great match! Will tune in now regularly. I am going to start my PhD this spring with a focus on Influenza and Ebola virus cell entry using cryoEM in the Chlanda lab in Heidelberg.

I don’t know if it is too late for the giveaway, but anyway here is my highscore. It’s a fun little game!

Thanks for your great podcast!



[he got 580]

Joyrell writes:

Hi everyone,

I gave the game a try, I do not have a knack for it just yet. Still, I wanted to have a chance for the book so I am sending in a rather pitiful score with the hopes that no one else had enough time to try the game. Your podcast has been a huge influence on my decision to pursue a Masters in microbiology once I have completed my bachelors. I spent last summer doing a research project in the Cameron lab at the university of Regina. It was there I discovered my true love, research. I have never been happier. Every moment in the lab makes me realize how lucky I am. I will be continuing my project this coming summer and am almost giddy with excitement every time I think about it.

Keep up the inspirational work,


[she got 30]

Noah writes:

Dear Professor Racaniello,

I’m probably too late (I forgot TWiV is weekly) but here is my high score anyway.

2100 (see attached screenshot)

Beng writes:

Hi Doctors,
Here is a screen capture of the highscore my daughter helped me to achieve. She was so enthusiastic about playing the game because she thought Prof Racaniello is going to personally deliver the book all the way from NYC to our house in Perth, Western Australia!


Peter writes:

Hi Vincent & Co.,

Here is a screenshot of my score: 1610

Love the show, it’s great to listen to while pipetting into the night. Keep up the fantastic work of making all of the papers discussed so interesting, and approachable.

A fan from Trinity College Dublin, Ireland.



Anthony writes:


I was listening to a video of Noam Chomsky speaking on the evolution of language.  He said — since it arose so suddenly — the mutation enabling the capacity for language must be something simple.  I thought that perhaps instead horizontal transfer delivered in a single step a complicated mechanism.  Googling language and virus as the search terms conjured up the video of Laurie Anderson.


Peter writes:

Dear Professors,

I am delighted to have won the Peter Hotez book. The clutch just went in my car so the timing was perfect. Thanks very much. Please send to the Zoology Building address below. My colleagues have already asked to have a look at it after me and I will order Peter Hotez’s blue marble book as soon as I am finished to follow up.

Thanks also for the information on the development of universal flu recommendation in the US. I will get my whole family vaccinated in future and be better able to better inform foreign students in Ireland.

Thanks again,


Peter Stuart

Zoology Building

School of Natural Sciences

Trinity College Dublin, the University of Dublin

Shallee writes:

Dear TWIVers;

I loved the podcast on ARC and dARC.  It arrived just after my Bioinformatics class had searched for and analyzed some human endogenous retroviruses.  They already had some gag protein sequences saved.  So, we spent most of the period digging into these sequences and discussing the possibilities of how these had evolved. Fantastic!  Thanks.

Shallee Page

Shallee (Pronounced like a cockney Shall He?) Page (he/his)

Assoc. Prof. of Chemistry

Marcucella Hall

Franklin Pierce University

Rindge, NH

Majda writes:

Hello TWIV team,

thank you for the interesting episode about flu vaccine. I have two questions regarding this topic:

  1. Is there a cumulative effect of flu vaccine protection? Is a person who gets the flu vaccine every year better protected than someone who got the vaccine for the first time? I would guess that there should be some epitopes that remain similar at least for some time and therefore the antibodies from one year may help during next years as well.
  2. You mentioned that big pharmaceutical companies do not make any money from flu vaccination. What does it mean? I guess they cannot do it for nothing. If I say it to someone who is against vaccination it does not sound very reliable. Is it possible to find how much money these pharmas make from vaccines in contrast with other medicines?

I am sorry for my English, hope it is possible to understand my questions.


Johnye writes:

Gentle Folks,

To add to the collection. Enjoy.

Johnye Ballenger


9 C, light drizzle