microbiology
mikethemadbiologist | October 1, 2007We're getting worse at washing our hands according to the Baltimore Sun. One thing I've said many times before, but it bears repeating: the best way to avoid getting sick is to limit contact with someone else who is sick. While that sounds obvious, one very good way to do that is handwashing. Handwashing breaks the 'transmission network' and essentially isolates the sick person. If you view preventing infectious disease as a question of how can I protect myself from disease, then we've already lost. The best measures (vaccination and handwashing) aren't just about protecting yourself,…
neurophilosophy | September 29, 2007Over the past few days, there have been numerous scary news stories about a "brain-eating" amoeba that has killed six boys and young men this year (three in Florida, two in Texas and one in Arizona, the most recent case being that of 14-year-old Aaron Evans, who died on September 17th).
The amoeba in question is Naegleria folweri, a thermophilic (heat-loving) free-living organism that is commonly found in rivers, fresh water lakes and soil all over the world.
N. fowleri infects humans very rarely, but infection is usually fatal. It normally occurs during water-related activities such as…
sporte | September 26, 2007For the record: Chlamydia is NOT a virus.
I am bummed. I like the little MicrobeWorld radio broadcasts, and the video podcasts are even more fun.
But I was perusing the archives and I found this:
I could ignore this if it came from a different source, but MicrobeWorld is produced with funding from the American Society for Microbiology!
Microbiologists are supposed to know the difference between bacteria and viruses. It's part of our training and big part of what we do.
I know, as scientists we're always supposed to follow the mantra of "buyer beware" and "be skeptical of everything…
sporte | September 7, 2007During the past few Fridays (or least here and here), we've been looking at a paper that was published from China with some Β-lactamase sequences that were supposedly from Streptococcus pneumoniae. The amazing thing about these particular sequences is that Β-lactamase has never been seen in S. pneumoniae before, making this a rather significant (and possibly scary) discovery.
If it's correct.
tags: DNA sequence analysis, antiobiotic resistance , microbiology, blastn
The way this sequence was identified as Β-lactamase was through a blastn search at the NCBI. And in fact, it was correct to…
mikethemadbiologist | September 5, 2007...then please take this survey (it's anonymous). The survey designers are trying to understand more about about the concerns of people affected by MRSA. The survey should take about 25 minutes to complete. You can take the survey here. If you know someone who has had a MRSA infection, please forward this link to him or her. Also, if your blog can handle it, please think about posting the link.
mikethemadbiologist | September 4, 2007In response to this post about annual influenza (also crossposted here), I received several emails and comments that missed the whole point. I am not denigrating the importance of 'other' diseases. AIDS and cancer are worth curing and preventing. My point about influenza is that preventing most of the deaths can be thought of as 'low-hanging fruit.'
Unlike AIDS or various cancers (there is no single 'cancer'), we don't need a medical or technological breakthrough that might or might not happen. We also don't need behavioral modification, such as STD awareness or smoking cessation…
grrlscientist | August 30, 2007tags: Lab 257, Plum Island,animal disease research, USDA, West Nile virus, Lyme disease, Dutch duck plague
After the recent outbreak of foot and mouth disease in the UK was shown to be the result this virus's escape from one of two nearby research labs, I thought it was timely to review a book that investigates this same occurrence in the United States. Lab 257: the Disturbing Story of the Government's Secret Plum Island Germ Laboratory (NYC: William Morrow; 2004) by Michael Christopher Carroll, is the riveting story of an animal disease research lab located on an 840-acre island that is only…
mikethemadbiologist | August 25, 2007ScienceBlogling Tara of Aetiology has co-authored a PLoS Biology article about HIV denialism and the internets. Go read it. The HIV denialists are clogging up the internet tubes...
sporte | August 24, 2007I began this series last week with a question about a DNA sequence that was published and reported to be one the first beta-lactamases to be found in Streptococcus pneumoniae. Mike has a great post about one of problems with this paper.
I think the data themselves are awfully suspicious.
So, last week I suggested that you, dear readers, go and find out why. I gave you a link to the abstract and a place to get started.
Perhaps that was too hard.
Sigh.
Okay, here's a little more help and another clue.
I highlighted the accession numbers. Post your guesses in the comments.
mikethemadbiologist | August 24, 2007This post by ScienceBlogling revere about the horrendous human cost of influenza is getting some serious exposure. This gives me an excuse to mention something I haven't in a long time:
Stop worrying about avian influenza. Get serious about 'ordinary' influenza.
Why? Last year, 'ordinary' influenza killed roughly 36,000 U.S. residents. That's about equal to breast cancer which kills 40,000 annually. Before the polio vaccine, the polio virus killed 3,000 people annually, and, even if you adjust for population increases, that number would be roughly 9,000 in today's terms. HIV/AIDS kills…
mikethemadbiologist | August 23, 2007It probably doesn't look like Marvin. (from here)
The data haven't been released yet, but that's what CNN is reporting:
The soil on Mars may contain microbial life, according to a new interpretation of data first collected more than 30 years ago.
The search for life on Mars appeared to hit a dead end in 1976 when Viking landers touched down on the red planet and failed to detect biological activity.
But Joop Houtkooper of the University of Giessen, Germany, said on Friday the spacecraft may in fact have found signs of a weird life form based on hydrogen peroxide on the subfreezing, arid…
mikethemadbiologist | August 23, 2007Forget smoking cessation. This is a patch everyone can use. From the August 10 edition of ScripNews (subscription only):
Iomai's traveller's diarrhoea vaccine patch shows promise
Iomai's investigational vaccine patch for traveller's diarrhoea has shown positive Phase II results in volunteers travelling to Mexico and Guatemala. If approved, it would become the first vaccine approved in the US for traveller's diarrhoea, says the company.
The patch is designed to treat traveller's diarrhoea associated with enterotoxigenic Escherichia coli (ETEC), which is responsible for most cases of the…
grrlscientist | August 22, 2007tags: researchblogging.org, Egyptian Rousette, Egyptian fruit bat, Rousettus aegyptiacus, Marburg hemorrhagic fever virus, Ebola hemorrhagic fever virus, Uganda, zoonoses, pathogen
Portrait of an Egyptian Rousette or Egyptian fruit bat, Rousettus aegyptiacus.
Image: Wikipedia
Like something out of a sci-fi novel, a man from Uganda died a horrible, bloody death from Marburg hemorrhagic fever this past July. As a result, scientists from the USA and the African nation of Gabon raced to the area to search for the source of this disease, and they may have finally discovered it. The team tested…
neurophilosophy | August 22, 2007A significant proportion of people with HIV/ AIDS develop neurological symptoms, such as impaired co-ordination, personality changes, deficits in learning and memory, and mania and depression.
HIV-associated dementia is difficult to treat; although highly active anti-retroviral therapy (HAART) has led to improved prognoses for patients, these drugs do not effectively penetrate the blood brain barrier. So, the brain can act as a "silent reservoir" for HIV, which can therefore cause lasting and irreparable damage.
Exactly how HIV causes dementia was unknown. But a new study by researchers…
sporte | August 17, 2007One time I was watching a football game on TV and they had a short quiz, called "You make the call" or something like that, and you had to watch a play and pretend to be a referee. A short video clip showed football players falling over each other. Then you were three possible calls that a refereee might make and asked to chose which was correct. After the commercial, the announcer would tell you which choice was right and explain why it was correct. I suppose this was a trick to make us watch the commercials, but I thought the game was kind of fun.
My SciBling "Mike the Mad" had a great…
mikethemadbiologist | August 15, 2007One of the things that's hammered into your head as a baby scientist is the importance of running controls. Typically, you run a positive control--a 'gamed' experiment where you know what the outcome should be and which tells you that the experiment is working--and a negative control which should not give any results at all (e.g., a PCR reaction without any DNA) to make sure there's no contamination or other spurious results. It's always puzzled me why people don't like to run controls because if you don't do the controls, you'll have to redo the experiment, which is a lot more work than if…
neurophilosophy | August 9, 2007
(From the Gilbert Lab at the University of Texas)
This carpenter ant (genus Campanotus), and the bullet ant in the first film clip below (Paraponera clavata), have fallen victim to parasitic fungi of the genus Cordyceps, which manipulate the behaviour of their host in order to increase their own chances of reproducing.
The spores of the fungus attach themselves to the external surface of the ant, where they germinate. They then enter the ant's body through the tracheae (the tubes through which insects breathe), via holes in the exoskeleton called spiracles. Fine fungal filaments called…
mikethemadbiologist | August 9, 2007...the signal peptide? Interesting. I'll start at the beginning.
One of the few bright spots regarding the problem of antibiotic resistance is that resistance typically infers a fitness cost to the bacterium, at least initially. In other words, the resistant strain usually grows slower than a nearly identical sensitive strain*. While compensatory mutations can lower or eradicate this 'cost of resistance', it is thought that resistance can't increase initially without favorable selective conditions--antibiotic use--due to the cost of resistance.
We'll need a little background about…
mikethemadbiologist | August 8, 2007MRSA is coming! Run for your lives!
....this little piggy had MRSA up its nose. A recent study from the Netherlands found that 39% of slaughtered pigs carried MRSA. This is particularly surprising since MRSA rates in hospitals in the Netherlands are remarkably low. Even in the U.S., the commensal MRSA frequency in humans is around 1.5%. What's up with the piggies? Here's the abstract; some additional comments afterwards:
Recently methicillin resistant Staphylococcus aureus (MRSA) was isolated from pigs and pig farmers in The Netherlands. In order to assess the dissemination of MRSA in…
neurophilosophy | August 7, 2007
From the BBC:
Microbes locked in Antarctic ice for as much as eight million years have been "resuscitated" in a laboratory.
Researchers melted five samples of ice from the debris-covered glaciers of Antarctica which range in age from 100,000 years to eight million years.
When given nutrients and warmth, the microbes resumed their activity - although younger microorganisms grew more successfully than the older ones.
According to the news story, the paper is published in the Proceedings of the National Academy of Sciences, but I couldn't find it at the time of writing…