Today’s collection of lunchtime news chum stories all have to do with the littlest things having big effects:
- High-O Silver! Recently, my wife picked up a new antibiotic gel at the pharmacy — an over-the-counter colloidal silver creme. I thought nothing of it (other than to try it and see it worked well) — after all, there are people who use colloidal silver to fight infections, although it has the side effect of turning your skin blue. Additionally, according to numerous studies, consumers may benefit from the silver specks’ ability to inhibit the growth of bacteria, fungus and other microorganisms, including disease-causing Escherichia coli and Staphylococcus aureus. So, I was intrigued by this Discover article about the new silver antibiotic gel — it seems that it contains silver nanoparticals that may harm humans and wildlife. The problem is that silver nanoparticles’ tiny size allows them to enter parts of living things bodies that other molecules can’t reach. This can damage the inner workings of cells and inhibit protein production. And of course, being stupid humans, we’re just tossing this stuff into the environment, along with plastic nanoparticles, gold nanoparticles, and copper nanoparticles.
- Battling the Bulge. Everyone has heard, by now, of the various bariatric surgical approaches for weight loss. Two of the best approaches are the Roux-en-Y gastric bypass operation and the vertical sleeve gastrectomy. One might think that these approaches work by reducing the size of the stomach, and thus reducing the amount of food one can eat and/or absorb. But if you think that, you would be wrong. There’s some new research on how obesity surgery really works, and it is astounding. It appears that these surgeries actually work by setting in motion a cascade of signaling changes in the gut and elsewhere. Those changes, in turn, reshape the mix of gut bacteria in ways that appear to turn up metabolic function, lipid metabolism and signals that tell the brain it’s time to stop eating. Researchers have already observed that certain bile acids circulate more copiously in the guts and blood of patients in the wake of bariatric surgery, but could only guess at why. They also have observed that the community of bacteria colonizing the guts of obese patients changes in the wake of bariatric surgery. Researchers just found that that one link between these two changes is a genetic “switch,” or transcription factor, called FXR. Increased bile acid unlocks FXR, which improves metabolic function directly. But improved FXR signaling also promotes the growth of gut bacteria that help regulate fat metabolism, and suppresses gut bacteria that is linked to weight gain and metabolic disturbance. The next step is to figure out how to create the FXR signalling through medicine, not surgery.
- Concrete Isn’t Forever. Most of us see something made of concrete, and we think “permanence” (well, I also wonder about the water trapped in the structure). But all of our concrete isn’t permanent, and that’s creating a problem. Here’s the scary headline related to this that caught my eye: Concrete-Dissolving Bacteria Are Destroying Our Sewers. The problem is that, within the sewer system, one set of microbes emits hydrogen sulfide, the gas that is also responsible for raw sewage’s unpleasant smell. This gas fills the empty space between the top of the pipe and the water flow. Another set of microbes living in this headspace turns hydrogen sulfide to sulfuric acid, which eats away at concrete, leaving behind gypsum, the powdery stuff you find in drywall. This turns the sewer pipes into wet drywall. Yuk. That’s worse than Orangeberg piping. The current solution is to put plastic liners into the concrete pipes, a process that is almost as expensive as digging them up entirely. A better approach might be to embed anti-bacteria in the concrete (but that can build resistance). Microbiologists are instead thinking about how to tinker with the water systems and DNA sequencing to create probacteria — bacteria in the water pipes that are harmless to humans (so they say) but can manage the sewer bacteria.
- [ETA] Bugs from Birth. Here’s a P.S. item from Andrew Ducker on how the birth process was designed to colonize us with beneficial microbes that help keep the bad ones out. The implication of this is that, as more and more women opt go to the Caesarian route for convenience, we are entering life less prepared with the good stuff we need to get us started. As the article notes, “the founding populations of microbes found on C-section infants are not those selected by hundreds of thousands of years of human evolution or even longer.” In other words — we are too safe for our own good.
Scientists like to say that this is a bacteria’s world, and we just live with it. After all, humans carry more bacteria cells than human ones, and without bacteria, we couldn’t live in the world. In fact, small microbes now are believed to be responsible for one of the greatest mass extinctions on earth! We need to think more about our indiscriminate use of antibiotics, and the impacts of our growing use of nanotechnology that we don’t fully understand.