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TWiM regularly receives listener email with corrections, comments, suggestions for show topics, requests for clarification, and additional information. A selection of these is archived on this page.
Dear TWiM team I saw this fascinating paper on how the variety of bacteria populating human skin can influence who mosquitoes chose for their blood meal.
Not really sure if it would be best covered in TWiM or TWiP as falls within the remit for both podcasts.
Composition of Human Skin Microbiota Affects Attractiveness to Malaria Mosquitoes
It appears that mosquitoes tend to avoid people with more diverse microbial communities on their skin as they contain bacteria that produce volatiles that repel mosquitoes.
Presumably once these particular bacteria have been identified then it may be possible to culture them to produce a mosquito repellent, presumably actually growing the culture on your skin would also work as a biological control, though I think it would be rather harder to market given most peoples fear of bacteria.
I just saw this engrossing documentary about lyme disease with a controversy about the existence of a chronic form of lyme disease. The movie might be worth a mention as a listener pick. It's 1 hr 44 mins long and can be seen online at http://www.hulu.com/watch/268761/under-our-skin. A web site with resources and trailer also exists as www.underourskin.com. The movie is several years old. Do TWIM panel members have any current information about the controversy and is progress towards resolution of what is affecting folks with chronic conditions they attribute to lyme being made? Unfortunately, as noted at the end of the movie, several key researchers have died, including one who had detected Lyme borreliosis in brain tissue samples from deceased Alzheimer patients. I would have liked to have them join the TWIM panel and discuss current activities.
First of all, let me congratulate the microbiology crew for bringing up such a fantastic podcast that makes microbiology so much fun. Since Dr. Moselio is very interested in mitochondrion i thought he probably would know the answer for my question. Its known that only mom's DNA is being passed to their progeny. Its also known that as you age there is continuous accumulating damage to mitochondrion thanks to the oxygen species. Now my point is why doesn't the mitochondrion which is from mom derived after a few rounds of replication accumulate damage and pass to the child. That doesn't happen (else we already would have high damage in mitochondrion). I hope my question isn't absurd.
I also would really love to hear an episode or 2 entirely dedicated to what we know of HIV on TWiV (Just like the malaria sequence episodes in TWiP). IF you do please focus on HIV genome controls by TAT.
On episode TWiM#22 there was a great snapshot of microbiology in clinic. I just am interested to know if Dr. Alfred have experiences regarding Burkholderia cases in infants. We just happened to see some in premature infants. If yes please light the area.
Am sorry for too many questions and comments. Once again thank you for the great great educast.
Al Sachetti answers:
To be honest I never heard of Burkholderia so if I've seen a case of it I never made the diagnosis.
I looked it up and it is more an infection of the immune compromised, especially those with cystic fibrosis. A case in an infant would be particularly unusual from what I can tell. Seems more of a plant pathogen that also infects livestock and is more of an opportunistic human pathogen. Just more proof, it's the microbes that rule the planet.
On another note, I ran into a pediatric ER doc from Chicago last week who told me they are seeing one of the worst Respiratory Syncytial Virus seasons ever. This has been our experience with more cases in the last few months than we have seen in the last 3 years combined. This is in the face of no Influenza infections at all this year.
Might be fun to do a Bench Top to Bedside show with an RSV Virologist and a physician on this one.
Have a great New Year.
Thanks so much for your podcasts. I find I am a person who learns best audibly and have just jumped into the science, history, medical and EMS blogs, I Listen to a podcast called SMART EM by a pair of ED docs, and they covered the issue of UTI in Peds. They do journal and study reviews and the found that there isn't any basis for the idea that untreated UTI causing kidney damage for Peds. I know, I know, but they took the time to ferret out all the info. Anyway, I am enjoying your podcasts. I don't think going back to school is something I can do, but about once a week I go to a class on virology, parasitology and microbiology. The tuition is great. No student loans. No sleeping in class.
Al Sacchetti answered: Jayne is correct and not correct depending on who you read. This is one of those topics that will continue to be debated as it is mostly "soft" science.
It is all based on retrospective case studies so you really can't design what would be considered a good scientific study to prove it. Such a study would involve not treating a cohort of children with urinary tract infections and following them and a second subset of treated children to determine if one group develops more hypertension than the other. Not an ethical study to perform.
The other confounder is that there are multiple other causes of hypertension that may overwhelm the cases caused by infant UTI's.
For me the take home message will not become clear for another two decades. That is how long it will take for this generation of treated children to grow old enough to really look at the epidemiology of their hypertension. (As an aside, it is one of those issues that really will not change our practices since we will always treat a UTI in a child.)
On a different note. What would you think about doing a TWIV on Hepatitis C with a Hepatitis C Virologist, a Transplant Surgeon, a Hepatologist and possibly a hepatitis C patient? From the Bench to the Bedside type of show.
Take care and continue the great work you do with the all the TW's
Hi Guys - I was wondering if you had seen the following article in about the lack of acorns being produced in the Northeast this year. In it they mention that the lack of acorns in the past is associated with crashes in the mouse population, then, the author says: "And because the now-overgrown field mouse population will crash, legions of ticks — some infected with Lyme disease — will be aggressively pursuing new hosts, like humans."
Currently here in Atlanta our oak trees are producing massive quantities of acorns. Every few years oaks will begin producing lots and lots of acorns in a season - a phenomenan thought to saturate their predators and try to increase the odds that ssome of their seedlings will germinate and take root. Is there any way that you could do a show (or part of) on some aspect of this Oak-mouse-tick-Borrelia story? It has the parasites (ecto - tick, endo-Borrelia) angle and it has this beautiful tie in to local ecology. I know it isn't typically what you do on the show, but if you can do some aspect of it that would be great. I am going to use this story in my non-science major introductory biology course next semester for some active learning in the classroom, and being able have my students listen to another TWIP/M/V podcast as preparation for those classroom sessions would be too perfect. Does Dr Gwadz have an expertise on the ecology of lyme disease maybe?
Thank you for the great shows, keep up the great work!
Georgia Perimeter College
Here is the link:
Here is an article in American Scientist which passes for a pretty good review on the subject: http://www.americanscientist.org/issues/feature/the-ecology-of-lyme-disease-risk/5
I'm greatly concerned about the harmful effects of nanotechnology. I'm old, but have grand kids, who already have to live with all kinds of junk in the environment. I guess it's a topic that fits in the virology category, too, since are not nanotech-sized particles in the viroid category? The scope of nanotechnology is so great that it looks like a wave of change, just like plastics, so perhaps it has to become an obvious and terrible hazard, like DDT or an epidemic before better controls will be considered. Just thought I'd ask what your take is on the topic.
I ran across a nice 3-part series from Marcy of 2010, if you want to use it as a springboard, or reference for listeners, although plenty of other discussion is easily found on the web.
Hi Vincent and hosts,
I have a theory, as to why mitochondria would be involved in programmed cell death. It makes sense that, if they are descended from parasitic bacteria, that mitochondria would have had the ability to kill cells. They may well have needed this in order to spread, from cell to cell.
It makes sense that evolution would adopt something already present, in order to kill cells, rather than inventing something new.
I have no proof, but it does seem reasonable.
Thanks as always, for your interesting group of podcasts.
In the discussion of copper, it should be noted that copper has long been added to marine bottom paints as an anti-fouling agent. Now however there is concern about deleterious environmental effects from its leaching out into the waters.
Barbara Hyde, MBA, CAE
American Society for Microbiology
First of all, thank you so much for providing myself and other microbiologists with this excellent podcast. Your very first episode was extremely fascinating to me, and I will be avidly waiting for all of the future episodes. I hope you and your friends can maintain this caliber for your podcast.
I am an analyst in the microbiology laboratory at a modest-sized pharmaceutical manufacturing company. For those of you that are familiar with pharmaceutical microbiology at a sterile manufacturing site, you would understand why the discussion of the laboratory studies on copper as an actual self-sanitizing material would be interesting. For the most part you talked about possible applications in hospitals, but I would love to hear Michael Schmidt's (and others') opinion on possible manufacturing design changes if the FDA were to ever support them. Currently, Laminar Flow Hoods, Isolators, and most equipment in a sterile facility seems to be made out of 316 stainless steel. You already mentioned that stainless steel can easily harbor bacteria on its surface, but would using copper as an alternative really be that much more effective? Stainless steel can be polished smooth enough to ensure no bacteria hide in cracks or irregularities in the surface when sanitizing agents
are used. Speaking of sanitizing agents, could you even hope to sanitize a copper material with a strong oxidizer like bleach or hydrogen peroxide? Even an autoclave would be brutal on copper utensils such as forceps or hemostats. You would almost be making disposable metal materials. I would love to see what the minimum concentration of copper you would need in an alloy in order to keep a 10^3 or possibly even 10^6 reduction in microorganisms! Also, I'd be very interested in seeing how a spore-forming organism reacts to contact with copper. Is the spore-formation process quick enough to save a Bacillus species organism from certain death? These are the kinds of questions that popped into my mind immediately, and I'd love to hear your take(s) on them.
On an unrelated note:
I'm a 25 year old analyst at this company with slightly over 4 years of industry experience. I would be ecstatic if you could take some time in an episode to describe the differences between industry and academic microbiology, focusing on some of the progression (or hierarchy) in those different fields. In my undergrad my classes were entirely pre-Med focused, and it was only by chance that I ended up in the industry. Now knowing what I do about pharmaceutical manufacturing, I wish that I had known more so I could have prepared a more efficient method of getting further in this field. An MBA would make becoming a manager/supervisor so much easier, and a PhD would make a Senior Scientist level more tangible to me. As it stands now I have no idea how to get further ahead, but a 5 year break from college keeps me reluctant to go back to school and start all over again.
Thank you once again for all you do, and best of luck in your research and with this podcast!
Hi, I'm a new student of microbiolgy at UBC, working in the Redfield lab. I found your podcast very informative and am looking forward to future episodes. If you are looking for interesting people for I'd like to suggest my supervisor Rosie. Among other things, she has a lot of interesting things to say about the recent arsenic bacteria issue.
Please say hello to Prof. Despommier for me, I've never met him but a few years back we talked about an unfruitful venture to get vertical farming going in Vancouver.
[Rosie Redfield blogs at http://rrresearch.blogspot.com/]