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Pigs not only inspire scientists via delicious, brain-sustaining pork products. See the latest pig-influenced developments in medicine and tech, from diabetes treatments to pig-urine-flavored cigarettes

We’ve got pork on the brain here this week at PopSci. Earlier today we told you about how cells from a pig’s bladder helped a man regenerate part of his severed finger, and if you’re a PPX player, you know we just rolled out an IPO regarding PETA’s recent offering of a million dollar prize for anyone who can grow meat sans-animal in a lab, hoping to negate the necessity for livestock. However, it will probably be a while before anything created in the lab will rival the one food that we can’t ever manage to stop thinking about, even for dessert—bacon.

As it turns out, pigs have been the inspiration for several other recent medical and technological innovations in the last few months.

One such instance of pig science is a report from a group of Russian scientists who are implanting pancreatic cells from young pigs that produce insulin into diabetics. The sample size is still quite small (only 4 people have received the treatment), but the results are worth watching. It seems that some of the patients with the injected insulin-producing pig cells have been able to drastically reduce their insulin intake over long periods of time. This could be a significant step towards the cure for a syndrome that has become exceedingly common within the past few decades. One drawback, however, are the fears that this could lead to the cross-species transmission of pig-borne viruses.

If pig-based diseases aren’t disturbing enough, how about we turn our attention to pig urine? High-density industrial pig farms serve as home to a large percentage of the world’s nearly 1 billion pigs, and with high-concentrations of pigs comes high concentrations of their often toxic waste products, which can wreak havoc on the environment. However, one company has devised a novel way of disposing of the urine by rendering the urea into plastics for household items, such as pig urine cups, pig urine bowls and pig urine spoons. Once the process is perfected it could be cheaper and more environmentally advantageous than the regular fossil fuel-based plastics. Other manures can be used, as well, and the organic compounds that are extracted can be potentially used in a variety of ways, including as flavoring for cigarettes. A line of pig urine flavored cigarettes could be an alternative stop smoking product if the patches, pills or gum just aren’t doing it for you.

Finally, out on the extreme end of pig-based research is the glow-in-the-dark pig. A while back Taiwanese scientists were able to genetically modify a litter of pigs with jellyfish DNA so that they would fluoresce green. Though the visual results are striking enough to justify the experiment, the true reasoning behind the experiment is to show that stem cells can be tagged with the same fluorescent molecules allowing their growth and development to be easily observed and studied.

I personally like to think that these scientists wanted to secondarily cure a condition that has plagued man since his inception: the late-night munchies. And what better way to solve it than with glow-in-the-dark bacon?

See how scientists are learning from the most common form of life on Earth to fight cancer, produce ethanol and maybe even grow crops on the moon

Germophobes and OCDers may want to stop reading now, or at least seriously consider only continuing with a bottle of Purell on hand—for today, we’re talking about bacteria, those squirmy no-see-‘ems that densely cover just about every surface imaginable here on Earth, including your own skin. However much hypochondriacal hatred the mention of them can bring about, as with other quasi-oxymorons like “good cholesterol,� we’d be in a lot of trouble if it weren’t for bacteria. No higher order life would exist without them; they keep us alive and support our economy, and, frankly, most would be happy to go about their business having nothing to do with us. There are only a relative few that keep us washing our hands constantly for fear of illness. It is this great ubiquity and diversity that allow scientists to put both natural and modified bacteria to work in a wide range of beneficial modern technologies.

One way bacteria can be put to work is by genetically reconfiguring certain types that are normally harmful, making them benign and giving them a new task. The U.S. drug company Advaxis recently announced a study using neutralized Listeria monocytogenes bacteria, which can cause food-poisoning-like symptoms in humans and animals, to fight certain types of cancer. Listeria is perfect for the job, because it tends to infect special cells in the immune system called antigen-presenting cells (APCs). At the onset of an infection, APCs direct the rest of the immune system to attack pathogens by carrying certain chemical tags unique to the intruder on its surface—sort of like offering a bloodhound the scent of its catch.

Using modified Listeria bacteria that carry chemical tags found in certain cancers, the body then uses the new Frankenstein bacteria to direct the immune system to focus its attack on the cancer. The process is currently in clinical trials, but early results on subjects with advanced cervical cancer have shown promising results.

Another potential bacteria-related cancer treatment is the possibility of safer radiation therapy. Recent research has indicated that certain proteins found in the flagella (the tail-like propeller used for locomotion) of the benign Salmonella bacteria can prevent intestinal cells from going through the process of apoptosis, a sort of controlled cell suicide that naturally culls old cells. Radiation exposure sets apoptosis into motion prematurely, causing damage to the lining of the gut and bone marrow cells. In the study, when the flagella protein is given to rats that are then exposed to radiation, the molecule protected most healthy cells from harm while cancer cells were still successfully targeted. This could lead to safer and more effective chemotherapy with fewer damaging side effects, or even protections for workers in radiation-contaminated areas or potential victims of “dirty bomb� attacks.

Bacteria could also play a large role in the future of fuel production as the world continues its hunt for fossil fuel replacements. Recent research by has indicated that bacteria could aid in the production of ethanol, the plant-based biofuel currently getting the most attention as a viable gasoline replacement.

Producing ethanol is currently messy business—so messy that several studies have shown that when all is said and done, the benefits reaped from using ethanol instead of gasoline can be all but cancelled out when the emissions released during the production process are taken into account. Cellulosic ethanol, the most promising type that can be derived from the cellulose found in the cell walls of just about any plant, can be especially tricky—efficiently breaking down cellulose into usable sugars is something even the human body has trouble with (see: your poo).

One potential way out of this Catch-22 is teaching the biofuel source plants to break down their own cellulose naturally. Scientists at Michigan State University are working on a specific strain of corn, called Spartan III, that is capable of doing just that. Spartan III is modified by inserting the genes of several bacteria species, including those whose job it is to break down cellulose in the stomach of cows, into the corn’s own genome. This results in the corn breaking down the cellulose found in its leaves and stalks, generating simple sugars that can be directly fermented into fuels without intensive environmental and financial costs. This method also helps preserves corn’s viability as a food crop, as it enables ethanol production from parts of the plant other than the edible kernels.

It has also been suggested, believe it or not, that bacteria could help create rocket fuel on the moon. Tests suggest that cyanobacteria, or blue-green algae, would thrive in the soils of the moon once NASA starts planned construction of a base there in 2020. Provided enough water and sunlight, the bacteria could survive off the lunar soil and leech out the heavy titanium and iron deposits that would prevent other crops from growing. This could be the first step in making the soil arable for some sort of sustainable plant growth. The cyanobacteria could then be broken down by other bacteria to form a fertilizer, and the methane released during this process could be harnessed to create rocket fuel (see a paper on this research - PDF link). It is even thought that the leeched out heavy metals could be collected and smelted into building materials. Now stay with me on this tangent: arable lands lead to crops lead to (hopefully) moon cows lead to milk leads to real moon cheese. I can’t wait.

As you can clearly see, not all bacteria are bad. And when we experiment with them they can sometimes lead to amazing discoveries. My own personal countdown for 100% lunar-farmed dairy products begins now.

The amazing lizard uses its hairy toes to defy gravity and its dynamic tail to always land on its feet if it falls. See how scientists are using the gecko’s tricks to design better robots, spacesuits and—just maybe—Spiderman gloves

Most people’s knowledge of geckos doesn’t extend much beyond the Cockney-tongued lizard hawking car insurance on TV. I won’t go into the implausibility of these ads, the least of which being that a gecko wouldn’t have a chance to survive Britain’s cold climate long enough to pick up an accent. They do, however, thrive abundantly in warm, tropical climates, and in total compose nearly 15% of all reptile species on Earth. If you’re fortunate enough to live in gecko country, you’ve probably seen them climbing and crawling over just about every surface imaginable, including the ceiling.

Naturally, this impressive ability to “defy gravity” by quickly attaching and detaching themselves from surfaces without losing their balance led scientists to question how and why, and studies seeking to answer these fascinating questions have resulted in a variety of useful technologies for we humans to use in robots, spacecraft and Spiderman-like climbing gloves.

Originally, it was thought that a gecko’s ability to cling to walls was due to a secretion of some sort of adhesive on the pads of their feet. But when scrutinized with modern high-power microscopes, the surface of a gecko’s foot revealed hundreds of thousands of tiny hair-like projections, called setae, which can be as small as one tenth the diameter of a strand of human hair and are themselves covered in even smaller projections, called spatulae, which are sometimes so tiny as to be smaller than the wavelength of visible light. Each time one of these setae comes into contact with a surface, the tiny hairs form a temporary atomic bond called a van der Waals force. This molecular bonding is relatively weak, but when multiplied over thousands upon thousands of setae, it becomes quite potent—strong enough that if every single setae was bonded to a surface, a typical adult gecko could support nearly 300 pounds of weight.

Another interesting facet of this setae foot design is that the adhesion is directional. As the gecko attaches its foot to a wall, since the setae are not all the same length, only some will make a connection. The gecko’s weight and direction of travel will bend some of the setae down allowing more connections with shorter stalks, increasing the bond. However, when the gecko moves its foot in the opposite direction the connections break and the foot detaches from the wall. This allows the gecko to walk along the surface, attaching and detaching without getting stuck, secreting any adhesive, or expending any unnecessary energy.

The unique nature of this directional sticking has vast potential for use by humans. Unlike most strong adhesives currently used, a gecko-inspired system using van der Waals forces doesn’t rely on tacky substances to stick, is reusable, self-cleaning and doesn’t leave any residues. And since gecko-based adhesives would be directional and based on the physical bond between surfaces, these adhesives could be used (and reused) in space or even underwater.

Possibly applications include gecko-foot materials that NASA could use on the boots of spacesuits or in multi-purpose adhesive tapes. These tapes could also be tailored to medical procedures to bind tissue together and might replace the need for sutures altogether, as recent research at MIT indicates. Since they can work in a fluid environment, the medical tape could be used inside the body, made biodegradable, or possibly deliver drugs. Then, of course, there’s the more far-out potential for the development of gloves that could give the wearer Spiderman-like climbing powers.

Aside from their amazing feet, more recent studies have shown scientists taking design cues from the function of the gecko’s tail. It seems that the gecko uses its tail as a sort of fifth limb that acts much like a bike’s kickstand to push itself back up against a wall if it begins to slip. This happens even if the gecko falls back up to an angle of 60 degrees from the wall.

Like cats, geckos always seem able to land on four feet if they fall. If its tail kickstand isn’t enough to regain its footing, the gecko also instinctively uses its tail as a sort of pendulum to rotate it back into a feet-down position in the blink of an eye. This discovery could serve as design inspiration for more efficient gliders or spacecraft with more precise control surfaces.

Data from these studies of the gecko’s amazing climbing abilities is currently being applied in several projects hoping to develop autonomous climbing robots. DARPA (no surprise there) has been funding many of these robots including the RiSE project or the Waalbot. Their hope is to to create search-and-rescue or reconnaissance ‘bots that can use gecko-inspired tech to climb treacherous surfaces and regain their balance if they fall.

The majority of this research is based on just the Tokay gecko, a larger variety found in southeast Asia. But further research into the 1,100 additional species of gecko could lead to a diversification and refinement of the potential uses of gecko-based technologies. And if it leads to gloves that allow us to climb walls, geckos may be selling us insurance for more than just our cars.