General biology

In the comments to this post on creationists'/HIV deniers' (mis)use of statistics, several people have been trying to argue that because overlapping membership in the two groups is limited, my comparison of the two is false. I explained: It's the *tactics* that are the same in both groups: misleading use of statistics as evidenced in this post, cherry-picking the lit, appeals to authority, grand conspiracies imagined, painting scientists as greedy and hopelessly biased, quote-mining, hell, they even each have their own prizes based on an impossible standard of evidence. Michael replied: Oh…
It's been a busy week over at Panda's Thumb. Three additional reviews of Jon Wells' Politically Incorrect Guide to Darwinism and Intelligent Design are up: First, PT's resident lawyer Timothy Sandefur writes about Wells' misleading characterizations of legal cases involving intelligent design. Next, Mike Dunford discusses Wells' chapter on speciation. Finally, Ian Musgrave tackles Wells' chapter on irreducible complexity. And, for an extra dose of Panda's Thumb, check out Nick Matzke's post highlighting his recent paper in Nature Reviews Microbiology on the origin of bacterial flagella.
Drug-Resistant TB in South Africa Draws Attention From U.N. The World Health Organization will hold an urgent meeting this week to seek ways to deal with deadly strains of tuberculosis that are virtually untreatable with standard drugs. The meeting, in Johannesburg on Thursday and Friday, comes in response to recent reports from a number of the world's regions about a small but growing number of cases of the deadly strains, known as extreme drug-resistant tuberculosis, or XDR-TB. "XDR-TB poses a grave public health threat, especially in populations with high rates of H.I.V." and few health…
If you're interested in biology and not reading Sandra Porter's Discovering Biology in a Digital World, you should be. As she notes in her profile, her passion is "developing instructional materials for 21st century biology," and it shows--she provides all kinds of little online experiments you can run yourself, even with minimal knowledge of molecular biology. She's recently finished a 4-part series on HIV. The experiment in a nutshell, as she notes: We are going to compare a protein sequence from a wild type, drug-sensitive, HIV virus with protein sequences from HIV samples that were…
Carl Zimmer has a few excellent micro-focused posts that you shouldn't miss. Yesterday the topic was new research demonstrating kin selection in amoebae, and earlier in the week, he wrote about Wolbachia, a fascinating bacteria that infects a large number of insects. (Those of you who've read Margulis' "Acquiring Genomes" may remember that infection with this bacterium can decrease fertility between individual insects who are differential in the presence of Wolbachia, potentially leading to reproductive isolation. Josh has more on this).
So, you may or may not be aware of the latest "challenge" to evolutionary theory--DI Fellow Jonathan Wells' new book, "The Politically Incorrect Guide to Darwinism and Intelligent Design." Following in the footsteps of Tom Bethell's "Politically Incorrect Guide to Science" (whose terrible chapter on AIDS I reviewed here), the book is just all shades of terrible. (As has been pointed out by many others who've read books in the "Politically Incorrect" series, they should just drop the pretense of "Politically"--simply "Incorrect" sums them up much better). I'll have a more comprehensive…
I blogged previously on the potential of bacteriophage, viruses that infect--and often kill--bacteria, in treating bacterial infections that are resistant to our current antibiotics. This is an area that's really just opening up, and while there is a lot of promise, there are also a significant number of obstacles. One thing I didn't mention, however, was the potential of bacteriophage for other public health measures--such as a bacteriocidal food additive. (More below) A mix of bacteria-killing viruses can be safely sprayed on cold cuts, hot dogs and sausages to combat common microbes…
As the conference wraps up, I just want to be sure to point you to some other areas where AIDS is being covered on ScienceBlogs. Every week, our Seed overlords pose a question to us (originally titled, "Ask a ScienceBlogger.") This week's question is: To what extent do you worry about AIDS, either with respect to yourself, your children, or the world at large?... You can find the collection of responses here. In more basic science, Sandra of Discovering Biology in a Digital World is starting a series on using HIV to prove some points about evolution. Looks like a great start to the series;…
I mentioned yesterday that one way to help prevent new HIV infections is to treat people who are infected with herpes, another sexually-transmittted virus that infects as much as 20% of the population in the United States. That may seem odd; how does treating one viral infection prevent infection with a second virus? Studies have shown that, generally, HIV isn't one of the more highly infectious viruses out there. For example, the hepatitis B and C viruses are transmitted via many of the same routes as HIV (such as sexual activity shared needles), but vary in their infectivity. If, for…
Ran across this interesting article in New Scientist on natural resistance to HIV. Researchers are launching a project to discover how certain people, dubbed "elite controllers", are successfully able to fend off the HIV virus without using drugs. More and more cases of such people - also known as "elite suppressors" - are coming to light. Unlike the sex workers in Kenya identified a decade ago as being HIV-negative despite their constant exposure to the virus, elite controllers are infected, and do develop antibodies to the virus, but at a very, very low level. More over at AIDS at 25.
The control and eventual eradication of the smallpox virus from the wild is one of the most heralded success stories in all of public health. Indeed, smallpox has played a central role in the history of vaccination. Even prior to Edward Jenner's use of the related cowpox virus to protect against smallpox disease, it was known that inoculation with materials from an infectious smallpox pustule or scab (dubbed "variolation") could protect an individual from death due to smallpox, generally resulting instead in a mild form of the illness. Jenner's observation that milkmaids seemed to be…
Paleontologists X-ray fossil embryos The article describes the cover story in this weeks' Nature, that PZ has already blogged about here. As the headline to the story suggests: Paleontologists have created detailed three-dimensional images of evolution's first multicellular creatures in their embryonic stages, some so detailed that they reveal more about the development of long-extinct creatures than scientists know about their modern counterparts. PZ has much more about the science and implications, and since that's his area I won't even try to elaborate, but what struck me was this quote…
Via Stranger Fruit, Panda's Thumb, and elsewhere in the blogosphere comes this Science paper discussing attitudes regarding evolution in a number of countries, including the United States. As noted in John's title, the U.S. comes in second....from the bottom. Only Turkey has a greater proprtion of citizens that doubt evolution. People sometimes ask why I bother even writing about "intelligent design" and other such supposed "challenges" to established scientific theories. Evolutionary biology is so overwhelmingly supported by the evidence, why even take the time to address those who deny…
The name "dengue" means "breakbone fever" due to the extreme bone pain it causes. The virus is a member of the flavivirus family, which includes the virus that causes yellow fever. Both viruses are arboviruses--viruses that are transmitted by arthropods. In the case of dengue and YF, the arthropod in question is the mosquito; specifically, the Aedes aegypti, an urban mosquito that lives in close contact with humans. Dengue infections cause an enormous amount of morbidity and mortality in areas where the virus is endemic. It's estimated to infect 50-100 million people each year. Though…
I mentioned just last month the dearth of research into what really makes an influenza virus easily transmissible from host to host, noting: If we had a better handle on the factors that caused an avian strain of influenza virus to be more efficiently transmitted among humans, then we could better focus our resources and know when to really sound the alarm--unlike now, when we're flying blind in many ways. A new paper in PNAS has started to do just that, and the research findings have prompted such headlines as Bird Flu Pandemic may not develop (via Effect Measure). Revere has already…
Regular readers may recall me previously discussing Rebecca Culshaw (for reference, threads can be found here and here). She's a PhD mathematician who wrote two articles discussing her departure from her prior research, which focused on mathematical models of HIV infection. I pointed out in one comment that her training is in math, and not biology, and that from her articles, she showed a very poor understanding of not only basic biological techniques (such as the polymerase chain reaction) but infectious disease epidemiology in general. Other HIV deniers responded that, because she did…
Chuck Darwin posed a very good question here that I'm spinning off into a new discussion. The work Taubenberger and others are doing on the evolution of influenza a century ago is fascinating and could very well be pertinent to prediciting future influenza virus genetic drift/shift, host-virus interactions, etc. However, I ask myself if the benefits of this work for future public health, as well as for general scientific interest, is worth the risks when it comes to biosecurity. With reverse genetics methods introduced a few years ago, any influenza virus can be generated through relatively…
A reader sent me a link to this site, which contained a reprint of a story by CBS 47 in Jacksonville. Mostly, it was a repeat of the story I already discussed, but it added this tidbit of information: The NPA teamed up with the Oklahoma State Department of Health to study the creepy crawlers. They took skin samples from 20 patients who claim they have the bugs, but were diagnosed by their doctors as delusional. Researchers found collembolan, a microscopic critter, in 18 of the 20 patients. Collembola feed on algae, bacteria and decaying matter. They thrive in wet or damp surroundings, and…
Somehow I missed this story in the June issue of Science: ...Jeffery Taubenberger of the Armed Forces Institute of Pathology (AFIP) in Washington, D.C., said that RNA found in tissue samples from pneumonia patients who died in 1915 shows that the virus's hemagglutinin--an all-important coat protein--is a subtype called H3. If confirmed, "that's tremendously exciting," says molecular biologist Ian Wilson of the Scripps Research Institute in San Diego, California. Knowing the virus's entire genetic makeup--which Taubenberger believes is possible--would shed fresh light on where the 1918 killer…
I've mentioned previously the potential role that mild or asymptomatic infections with influenza may play in transmission and evolution of the virus. Right now, most of our reports of H5N1 have been due to serious infections that caused a patient to seek medical care. These cases are the tip of the iceberg in a normal influenza outbreak, when most of us don't have physician-diagnosed influenza. Instead, we recognize the signs and symptoms, and stay at home to ride it out. Is this happening in Indonesia, Thailand, and elsewhere? For every person who shows symptoms of H5N1 infection, are…