Courtesy esteraseI bet regular bacteria have posters of their favorite superbug hung on their bedroom walls. I mean superbugs are just so much cooler than regular bacteria; they’re kind of the bad boys of the bacteria world. Regular bacteria do what they are told: they keel over when exposed to disinfectants and antibiotics. But not those rebellious superbugs. Superbugs have some kind of genetic mutation that allows them to survive in hostile, antimicrobial environments. Basic principles of natural selection come into play: the mutant bacterium survives in the presence of the antibiotic/disinfectant and then goes on to produce other bacteria with the same mutation, ultimately creating a new resistant colony. In this scenario, exposure to the antimicrobial agent (the antibiotic or disinfectant) is imperative. However, scientists now think that another scenario exists; one in which exposure is not required. In a recent study, these scientists found that the use of disinfectants in hospitals can lead to bacterial resistance to antibiotics, even if the bacteria haven’t been exposed to the antibiotics.
Researchers from the National University of Ireland added increasing amounts of disinfectant to petri dishes full of Pseudomonas aeruginosa (a bug that causes pneumonia in hospital patients, among other things) and the bug became immune not only to the disinfectant, but also to ciprofloxacin- the antibiotic used to treat the bug. Superbugs are essentially using their exposure to disinfectants as “teachable moments” for resisting antibiotics.
This is significant because now it seems that bacteria have one less hurdle to overcome in their mission to cause serious harm to patients (that’s not really their “mission,” I say that for dramatic effect). If superbugs can resist the disinfectant slathered on the countertops and doorknobs of hospitals, it’s possible that they could go on to infect patients who “for some reason” won’t respond to the antibiotics. Man, regular bacteria must be so jealous.
The manufacture of replacement body parts just might happen this year. Organovo just took delivery of the world's first production grade 3D bio-printer developed for them by Invetech.
The printer includes two print heads, one for placing human cells, and the other for placing a hydrogel, scaffold, or support matrix. The position of a capillary tip, can position droplets of "ink" containing virtually any cell type, with micron accuracy.
"Invetech plans to ship a number of 3D bio-printers to Organovo during 2010 and 2011 as a part of the instrument development program. Organovo will be placing the printers globally with researchers in centers of excellence for medical research." Organovo press release
With a new Sherlock Holmes movie due to open on Christmas day, there's the usual renewed speculation about what was really behind the eccentric literary detective's brilliant yet strange methods. Read about it here.
Yesterday in Washington, D.C., operations in two hospitals swapped 13 kidneys between 26 different bodies in the largest kidney transplant process ever conducted. Most of the recipients had conditions creating a situation where it was hard to match a kidney for their body. But they had to procure a donor for another hard-to-match recipient. Then the doctors mixed and matched all the donors to find the right recipients making for the record operation. Read about it all right here.
For the first time, a team led by Yale University researchers has used nanosensors to measure cancer biomarkers in whole blood. The new device is able to read out biomarker concentrations in a just a few minutes. Extremely small concentrations are being measured, the equivalent of detecting a single grain of salt within a swimming pool size volume of liquid.
"The new device could also be used to test for a wide range of biomarkers at the same time, from ovarian cancer to cardiovascular disease, Reed said. Science Daily.
Authors of the paper, "Label-free biomarker detection from whole blood", include Eric Stern, Aleksandar Vacic, Nitin Rajan, Jason Criscione, Jason Park, Mark Reed and Tarek Fahmy (all of Yale University); Bojan Ilic (Cornell University); David Mooney (Harvard University).
Distinct components within the sensor perform purification and detection. A microfluidic purification chip simultaneously captures multiple biomarkers from blood samples and releases them, after washing, into purified buffer for sensing by a silicon nanoribbon detector. This two-stage approach isolates the detector from the complex environment of whole blood, and reduces its minimum required sensitivity by effectively pre-concentrating the biomarkers. Nature Nanotechnology, Dec 13, 2009
Courtesy very little daveOne hates to be outdone. I mean, all of a sudden I’m given to understand that not only am I the resident poop expert (and how do you think that feels) but that I’ve been shirking my duties in covering the scatological sciences, and that fecal subject matter is slipping right between my fingers! It’s humiliating on several levels.
Thank goodness for the internet, eh? Because look what just fell in my lap: an eleventh-hour entry for most bizarre poop story of the year. A couple of 20-something designers with years of experience in the arts and a couple crazy weeks of education in synthetic biology were the talk of the town at this year’s International Genetically Engineered Machine Jambori. Why? Because of their briefcase full of human feces.
It wasn’t real human feces, of course—they’re artists, not miracle workers. But it represented a coming revolution in pooping. The wax poop models, you see, were all the colors of the rainbow (over a predictably colored base). The team of undergraduates they collaborated with have been working on genetically engineering strains of the E. choli bacteria that will change color in the presence of certain compounds. Currently, the new strain (now called, har har, E. chromi) will turn orange, red, brown, purple or yellow in the presence of arsenic, the exact color depending on the amount of arsenic. (“Brown”?)
Aside from brightening up the gloomy bowel movements of people suffering from arsenic poisoning, the team of scientists and artists has proposed that the technology could be used in the future for diagnosing diseases. Just swallow a little capsule, say, and the bacteria inside could tell you if you have cancer. It would be like reading tea leaves, kind of, but in a bigger cup, and without the leaves. (Imagining finding out from your Technicolor poops that you have cancer.)
Sadly, this application is a long way off. Aside from color-coding the bacteria to different diseases, it would have to be engineered so that our immune systems couldn’t destroy it before it changes color. One wonders, too if creating a strain of E. choli that is invisible to our immune systems might have a new set of issues to overcome.
I hope that they realize the recreational potential of any drugs to come out of the project.
Courtesy Hardyplants Almost three years ago, I wrote about how farm animals were being modified genetically to produce milk and eggs containing pharmaceuticals.
A Dutch biotech firm, appropriately named Pharming, has been milking rabbits experimentally for years. They recently developed a drug called Rhucin, which they extract from rabbit milk. The rabbits have been outfitted with a human gene that produces a protein called C1 inhibitor in their milk. Rhucin can be used to treat people with hereditary angioedema.
"Human C1 inhibitor can be obtained from donor blood, but our … product can be produced in unlimited quantities from a scalable and stable production system, and there are no safety issues in terms of [blood] viruses National Geographic."
If the drug is approved, Pharming will start milking a herd of about a thousand rabbits. The method is similar to milking cows except that the milk sucking attachments are smaller.
Mice are being milked in Russia for lactoferrin which normally is found in the breast milk of humans. Lactoferrin protects babies from viruses and bacteria while the infants' immune systems are still developing. Milking mice is very difficult, and is only a step toward larger animals such as rabbits, goats, or cows being bioengineered.
The ultimate aim of the Russian team, and of similar research projects in other countries, is to extract lactoferrin from the milk and use the protein to create healthier baby formula. National Geographic
Officials in Cardiff confirmed today the world's first cases of human-to-human transmission of Tamiflu-resistant H1N1 influenza. It's not unexpected, but it is worrisome. Even though flu cases are down here in Minnesota and across the US, keep washing your hands!
Here's a nice round up of opinions and press coverage of the controversy revolving around changing the beginning age for mammogram testing in women from 40 to 50. In the past several years having personally known several women under the age of 50 dealing with breast cancer, I have to admit I was dumbfounded by this new recommendation.