General biology
tsmith | July 24, 2006Evolutionary biologists sometimes think we microbiology people have it easy. "No one doubts the germ theory!," they claim.
Au contraire, mes amis:
Do some research Tara. Then you will be ready to start from scratch again, forget the germ theory nonsense and become a real scientist.
And I bet this insult will sound familiar to many used to dealing with the anti-science brigades:
Evidence is all around and you have as much evidence as I do. The sole difference between you and me is that you are still blindfolded by a century of dogmatic thinking and are not able to see the evidence.
You…
tsmith | July 21, 2006The lastest edition of Mendel's Garden, a genetics carnival, is up at Viva la Evolucion!
tsmith | July 19, 2006 I wrote here that pili--long, filamentous surface molecules involved in adhesion and bacterial "sex"--had recently been discovered in gram positive organisms; pecifically, in group A and B streptococci (Streptococcus pyogenes and Streptococcus agalactiae, respectively), using a genomics approach. Though this publication is quite recent, this is a fast-moving area of research, as evidenced by two new papers which extend this earlier research into pili in the group B streptococcus (GBS).
A new study published in Molecular Microbiology further analyzes the role of pili in GBS. This is a…
tsmith | July 18, 2006 I've mentioned previously the role, or potential role, that bats play in disease transmission. They have long been suspected, and recently identified, as hosts for the Ebola virus. (Whether they're the main reservoir species and what--if any--role they play in transmission of the virus to humans remains to be determined). They've also been implicated in the emergence of SARS and Nipah virus, and of course, have long been associated with the maintenance of rabies virus. A new paper reviews the role of bats in the maintenance and emergence of novel viruses.
Bats represent a huge portion…
tsmith | July 17, 2006Listeria monocytogenes is a gram-positive, rod-shaped bacterium. It can be found in the environment as a soil inhabitant. However, it also can be a frequent contaminant of our food supply. As the latter, the bacterium is a significant public health concern, as it is capable of causing serious infections. Listeriosis (infection with Listeria) causes ~2500 serious illnesses and 500 deaths each year in the United States, and the hardest-hit are those with poor immune systems due to age (the very young and old), other immunocompromsing conditions (such as chemotherapy, organ transplant, or…
tsmith | July 15, 2006More interesting stories that I didn't get to this week...
Ewen is looking for volunteer producers for his radio show. If you're in his neck of the woods and would like to learn about science journalism, drop him a line.
Mike notes that MRSA is winning the war on drugs, due in part to dirty needles and a lack of needle exchange programs.
Orac discusses the latest Geiers drama (those would be the folks who've been most prominent in pushing the vaccination/autism link here in the U.S.) Turns out a court recently laid the smackdown on them, Kitzmiller-style.
More sequence information has been…
tsmith | July 13, 2006I mentioned in this post on Ebola that I thought the authors were doing a bit too much extrapolation regarding their statement that the evolution of sociality in hominids has been constrained by pathogens such as Ebola. I didn't elaborate on that topic because it's a bit too far afield from my areas of expertise, but John Hawks has much more on the topic of pathogens and fitness in primate groups.
tsmith | July 12, 2006 The good Dr. Flea has taken some flack previously for comments he's made regarding the treatment of ear infections (or rather, the non-treatment of such). As he notes, most ear infections resolve without antibiotics. Despite this, ear infections are the most common illness for which children visit a pediatrician, receive antibiotics, and undergo surgery in the U.S., at a huge economic cost. A new paper in the Journal of the American Medical Association suggests at least some of that cost is wasted, because the bacteria are present in the form of antibiotic-resistant biofilms.
A biofilm…
tsmith | July 11, 2006 Longtime readers know of my fascination with Ebola. Much of it is fueled not by the fact that it's a major killer of humanity, because it's not: in 30 years, it's been responsible for a bit less than 2,000 human infections, and ~1,200 deaths. Bats have long been suspected to be a reservoir of the virus, and recent studies have confirmed that they can carry the virus.
With at least one strain of Ebola (Ebola Reston), we know that our primate cousins are more severely affected than we are. This strain has been found to infect captured primates brought into the United States from the…
tsmith | July 10, 2006...but luckily, I'm set straight over at Effect Measure, where Revere completely refutes my silly notion of mutations in H5N1 by citing this excellent guest commentary in the Greely Tribune (where their top story today is about a hot dog from 1952). The commentary is titled "Bird flu a lame claim to evolution theory" and written by one Mike Martin, former editor of Ag Weekly Magazine. He certainly demolishes my silly science-y notation of just what "mutations" (such as those discussed in the Nature article I cited use for analysis) are all about:
But now, "mutation" is being redefined to…
tsmith | July 8, 2006Holy cow, it's Saturday again already. Since this was a short week, I didn't have as much time for posts or for story-gathering, but there are still a few goodies I missed:
I was planning on highlighting this new research that showed, once again, no link between vaccination and development of autism. But then I decided not to re-invent the wheel, as Orac already covered it extensively.
Similarly, Mike highlights a story drawing attention to the under-diagnosis of influenza in children, and its ramifications on the health of the rest of the population.
Malaria continues to be a scourge…
tsmith | July 7, 2006Those of you who have followed creationism/intelligent design literature over the years have probably felt as if you're living in an alternate universe sometimes. In that literature, many times it seems as if "up" means "down" and "highly supported by the evidence" means "a theory in crisis."
You may not have been following the comments to this thread on AIDS (and lord, I can't blame you), but if you have been, you've seen a similar phenomenon, where it's suggested that mutations found in RNA viruses are just due to sloppy lab work, essentially blowing off an entire field of research.…
tsmith | July 6, 2006So, today apparently is "blog about diarrhea" day. Hope no one's eating lunch. (One of the upsides of being a microbiologist is that we can talk about blood and gore and bodily fluids while we eat and no one gets grossed out. Or, perhaps, that's a downside. Anyway, I digress...)
Two still hospitalized, four treated after E. coli outbreak at daycare
Six confirmed cases of a serious E. coli infection and four additional "suspected" cases are being looked into by the [Tennessee] Department of Health, according to Debbie Hoy of the agency's Cookeville office this Tuesday. All of the infected…
tsmith | July 1, 2006More interesting topics, too little time...
Mike discusses the dearth of qualified people to work in clinical microbiology labs--and the effect it may have on your health.
I'm a wanna-be history nerd. I really enjoy the topic, but as a science major, I didn't have a lot of time to take formal coursework in college, and since then much of my reading has focused on historical issues that are somehow related to science or medicine. So, there's a new blog to update me on all the other cool history news.
I've had several posts on butterflies and moths this week. It's also a theme at…
tsmith | June 30, 2006Sure, predator cats may have dined on our ancestors, but it seems we gave them ulcers (or, more correctly, passed along the bacterium that causes them) when they ate us.
Boo-yah! Take that, Simba.
tsmith | June 30, 2006 One of the things I love about science--but that can also be frustrating--is that every new piece of information leads to a new unanswered question. We've learned so much about microbiology and human disease since the time of Koch and Pasteur, but in many other ways, we're still at square one. One reason is because research over the last century has largely focused on disease-causing organisms--and within those, many studies have focused on identifying factors that allow these organisms to cause disease. This concentration has led to many breakthroughs (such as vaccine targets), but it…
tsmith | June 29, 2006 People make terrible jokes about "mad cow" disease. ("Why is PMS called PMS? Because mad cow was already taken.") Pundits use it as an example of an over-hyped disease (and to be fair, estimates of total cases due to the consumption of contaminated beef in the UK have varied widely, ranging from a few thousand up to well over 100,000). Vegetarians note it as one benefit that comes from their soyburgers. Everyone, it seems, has an opinion.
So-called "mad cow" disease, in humans, is a progressive neurological disorder more correctly called variant Creuzfield-Jacob disease (vCJD).…
tsmith | June 28, 2006 Especially in religious circles, much has been made about the "uselessness" of condoms for the prevention of infection with the human papilloma virus (HPV). This is the virus that is responsible for almost all cases of cervical cancer, against which a new vaccine was recently approved (for more background, see this post). Approximately 20 million Americans are currently infected with HPV, and over their lifetime, about half of sexually active adults will be infected at one point. Though most strains of the virus are harmless, a small portion of them cause cervical cancer in women, a…
tsmith | June 28, 2006I mentioned we were out camping over the weekend in central Iowa. After our first close encounter, I figured we might as well make a weekend out of it, so Sunday we headed to the Reiman Gardens at Iowa State University (and specifically, the Christine Reiman butterfly wing):
The new 2,500-square-foot indoor Christina Reiman Butterfly Wing is the "jewel" of the Gardens. Designed to look like a butterfly in flight, it is a year-round tropical garden filled with exotic and native butterflies from six continents.
I have tons of pictures, so I'll break them up into a few posts, starting below.…
tsmith | June 27, 2006 I blogged a few months ago about a case of plague (due to the bacterium, Yersinia pestis) in a woman in California. I'm still doing some reading for the promised post on Black Death, CCR5, and other topics discussed in the comments section, but in the meantime, I wanted to alert y'all to an ongoing outbreak of the disease (in the pneumonic form, meaning the bacteria is present in the lungs and therefore is person-to-person transmissible) in the Democratic Republic of Congo:
The sole aid agency fighting an outbreak of pneumonic plague in the remote lawless corner of the Democratic Republic…