General biology
tsmith | May 3, 2006It's been awhile since I've discussed prions on here. (Indeed, so long that the last time was on my old blog, but I imported a few of them that can be found here, here, and some background on prions here). Allow me to copy a bit of that to re-introduce the topic:
Prions are, of course, the transmissible agents that cause diseases such as kuru and Creutzfeldt-Jakob in humans, and related disease such as "mad cow" disease, scrapie, and chronic wasting disease in animals. Though there was initially much controversy about these agents in the early years (most notably, because they did not…
tsmith | May 3, 2006For anyone interested in a short review of nanoparticles as ligands (which I mentioned here but obviously isn't my area of expertise), there's a review in the April issue of TRENDS in Biotechnology (volume 24(4):143-145 in case the link doesn't work). As always, you can drop me a line if you don't have access to the full text. (And it's easier for me if you actually email rather than leave it in the comments--that way I don't forget about it!)
tsmith | May 2, 2006...asks a letter to Nature.
One might think that academic machismo or realism would cause scientists to downplay their surprise, but, on the other hand, overstating the level of astonishment may occur when striving for media attention.
I don't think that it's an outcry for media attention, but I don't know--is the phrase "surprising results" overused? Is there something better to say when something didn't turn out as you expected?
(Via Complex Medium)
tsmith | May 1, 2006[From the archives; originally published Nov. 3, 2005]
Ebola is one of my favorite pathogens. With the reputation it has, many people assume it's killed many more worldwide than it actually has. People hear of Ebola and all kinds of grotesque images come to mind: organs "liquefying" (doesn't really happen quite like that); bleeding from every orifice (okay, that one can be on-target); the victims dying a horrible death from a virus with an incredibly high mortality rate. There are four known subtypes of Ebola, named for their place of isolation: Ebola Reston, Ivory Coast, Sudan, and Zaire.…
tsmith | April 29, 2006More topics I'd have covered this week, given endless time and energy:
An update on the Chikungunya outbreak I discussed here (and see this comment on the outbreak from a medical entomologist in the region dealing with it first-hand).
Orac on viruses as cancer treatment, inspired by a recent episode of House (more episode reviews by Scott at Polite Dissent can be found here).
An update on mumps activity from the Iowa Department of Health. I haven't written about this in a few days because there's not much more to tell. Cases are still increasing, and they're recommended that students…
tsmith | April 28, 2006After hitting on the topic of sexy scientists earlier in the week, this one is kind of the flip side. I probably don't need to tell this audience that a lot of biology ain't exactly glamorous. Sure, there are biologists out there who never have to get their hands dirty, but many of us routinely grow up liters of stinky bacteria, or execute mice or other animals (my own gradute work, for example, involved lots of "spleen homogenization"), or monitor roadkill. Another common project is investigating feces, which can tell us all kinds of wonderous things. So, earlier this week that's what I…
tsmith | April 28, 2006Nanotechnology. What does it mean to you? How does it affect health? Does the phrase only conjure up images of Crichton-esque nanobots with a sinister motive?
Nanotechnology is a field defined solely by its size. By definition, it involves the manufacture and manipulation of materials at the atomic or molecular level--materials which are typically less than 100 nanometers in diameter. (For comparison, a human hair is roughly 50,000 nm thick, and a piece of paper 100,000 nm thick).
This technology has potential applications in a host of fields. For example, it's been used as a…
tsmith | April 26, 2006Novel Swine Influenza Virus Subtype H3N1, United States
In several of my influenza posts, I've discussed ways that the viruses can evolve. These are termed "antigenic drift," where the virus accumulates small mutations in the RNA genome; and antigenic shift, where large sections of the genome are swapped, generally in their entirety. While it was long thought that the latter was the most likely type of mutation to cause a pandemic, we now know that even the right kind of antigenic drift may be enough to allow a novel influenza virus to enter the human population, which seems to have…
tsmith | April 25, 2006Yeah, I think the title about covers it.
This week's Grand Rounds is up over at The Health Business blog. A few posts I'd like to highlight this week: this one at inkycircus about a pinworm infestation, complete with video link. (Probably not for the faint of heart!)
How evil (ew ew ew ew) is this: after laying eggs around the anus, the female worm secretes an itching agent, which causes the host to scratch his or her ass, thereby transferring the eggs to the fingers, a mere hop skip and jump away from more oral ingestion. And so, the ew ew ew ew ew EW life cycle continues. But take…
tsmith | April 20, 2006Though much of the attention to and reports of intelligent design/creationist shenanigans come from the United States, we're certainly not the only ones inundated with deniers of evolution and other sciences. A self-described UK evolution "sceptic" is journalist Melanie Phillips, who writes for The Daily Mail. She's annoyed many scientists in the country due to her views not only on evolution, but also on vaccination (such as this article from earlier this year), drawing the ire of many who point out that she doesn't understand the underlying science.
She's proven her critics correct…
tsmith | April 19, 2006
Lingerie makes hagglers happy-go-lucky
Quoth the Nature summary:
It seems that the more macho a man is -- at least according to his hormones -- the more the sight of an attractive woman will affect his judgement.
Researchers at the University of Leuven in Belgium asked men to play an ultimatum game, in which they split a certain amount of money between them. High-testosterone men drove the hardest bargain -- unless they had previously viewed pictures of bikini-clad models, in which case they were more likely to accept a poorer deal.
Okay, so it didn't exactly make them "stupid," as the title…
tsmith | April 18, 2006I started this as a comment to this thread, but perhaps this is enough for its own spin-off discussion. IndianCowboy said:
I'm not denying the influence of these genes on one's ability to maintain a certain weight. I'm not even denying the size of their influence, but one thing that bothers me is that many researchers, bloggers, reporters, whatever impute more into the findings than they should.
And I agree with that. Clearly it's not all genetic, and diet + exercise play a large role. Additionally, any one genetic locus (which is what's usually found in a study) alone is unlikely to be…
tsmith | April 17, 2006An interesting new paper has come out recently, reviving discussion of the effects of "nature" versus "nurture" in the development of obesity. Certainly everyone knows someone--or perhaps, is that someone, who can sit down and finish off an entire pizza without gaining an ounce, while others of us tend to gain weight just from looking at food. How much of our weight is due to our eating and exercise habits, and what's due to our genetics?
Anyone who even browses the health section of their local paper or online news source (or really, anyone who's not been living in a cave for much of the…
tsmith | April 15, 2006I don't know how other bloggers decide what to post. For me, everytime I run across a "oh, that would be so cool to discuss" topic/link/story etc., I copy the topic/link/story etc. into a new entry here, hoping to have time to elaborate on it at a later date. Some of them I get to--some of them just drift slowly to the bottom of the pile, untouched. But they're still interesting topics, so here are a few more that I didn't have time to write about, and as new topics come up, probably won't be able to get to in the immediate future:
A recent CNN story referring to the hygiene hypothesis.…
tsmith | April 13, 2006 Okay, so I lied. I was planning to wrap up the emerging diseases and zoonoses series with the post on monkeypox, but I think I'll just continue it as a sporadic event, since a new paper fits into the series perfectly.
I talk a lot here about streptococcus. As regular readers know, there's a good reason for that. Though my main research right now is on Streptococcus agalactiae (group B streptococcus, GBS), I also have a project working on a related organism, Streptococcus suis. As the "suis" name suggests, this is mainly a pathogen of swine. Indeed, it's kind of the pig equivalent of…
tsmith | April 12, 2006Not that one. This one. (Complete with video, even!).
You might think a catfish on land would fare as well as an elephant on roller-skates, but a new study reveals they slither around and adeptly catch insect meals.
The finding helps scientists imagine how ancient fish made their first hunting trips ashore prior to evolving into land creatures.
(Continued below)
Having a mobile neck is key for hunting on land--it allows the catfish to move its head up and down to stab at prey. Mobile necks are a feature usually reserved for land animals called tetrapods.
Recent discoveries of early…
tsmith | April 10, 2006I wrote previously about a recent study that found all sorts of bacterial diversity in a place once thought to be rather barren--the human stomach. One of the species they discovered appeared to be related to an extremophile--microbes that live in extreme environments (in this case, a relative of one that could withstand incredibly high doses of radiation). A new story from the BBC reports the discovery of another extremophile in a place one may not expect it (or at least, may not expect the one they found):
Researchers have found traces of a heat-loving bacterium that may live beneath a…
tsmith | April 7, 2006 For the final post of the series, I want to discuss yet another outbreak, this one a bit closer to home: that of monkeypox in the United States in 2003.
First, I should note that "monkeypox" is a bit of a misnomer. Though the virus--a relative of smallpox and cowpox--can infect monkeys (and humans), the reservoir host is likely a rodent. Previously, monkeypox had been found mainly in sub-Saharan Africa, in forested regions. 2 clades of the virus had been identified. One was common in West Africa, and generally didn't cause severe disease when humans became infected with it. The other…
tsmith | April 6, 2006...is up over at Complex Medium, so head over there to check out the best posts on our abundant little friends from the past 2 weeks. Lots of good stuff, but as Ewen notes, it's a bit bacteria-heavy...where are all the virology folks out there, huh?
tsmith | April 5, 2006...but just haven't had the time to do more extensive write-ups. So, a mini carnival of good stuff:
First, as other Sciencebloggers have noted, Seed is sponsoring a writing contest. $1000 dollar top prize and publication in Seed to the winner.
Cervantes at Stayin' Alive writes about the cost of pandemic preparedness--you might be surprised that it's, well, nothing so far. You get what you pay for?
Joseph has a post on Ebola examining the claims made by Eric Pianka that have received so much attention lately.
Some Ohio infectious disease news: tuberculosis found in illegally-transported…