Scientists sometimes just prove the obvious, like that men and women are different. If we can talk body without talking bawdy, there are some new discoveries about body works that should put a spring in your step today about how your body works.
Muscle milk: Whether you’re brawny or scrawny, you care about muscle. The most assiduous bodybuilder, though, should thank a tiny little signaling molecule that makes that burn lead to a good flex. Next to a photo of big delts and biceps, Stephanie Pappas on Live Science explains:
The secret lies with a chemical factor produced by muscle cells during work (such as during weight lifting) that signals muscle stem cells to multiply and take on the load. The substance, serum response factor (Srf), apparently triggers muscle stem cells — dormant cells capable of differentiating into muscle cells — to proliferate and become muscle fibers. More muscle fibers means bigger overall muscles and more strength.
A researcher in France called this “unexpected and quite interesting.” Gym rats can hope that what works in mice will also work in men (women, too).
Eye stash: Speaking of stem cells, there’s a good source of adult stem cells right in your eye, reported PhysOrg.
In the future, patients in need of perfectly matched neural stem cells may not need to look any further than their own eyes. Researchers reporting in the January issue of Cell Stem Cell, a Cell Press publication, have identified adult stem cells of the central nervous system in a single layer of cells at the back of the eye.
Amazingly, these cells are produced in the embryo and remain dormant throughout life; therefore, “You can get these cells from a 99-year-old,” a researcher at the Neural Stem Cell Institute in New York. The cells can be isolated and grown into other body cell types. “It’s kind of mind boggling.”
Talk the dog: Your dog understands you better than you think. You can do a kind of mind-meld with your dog; Fido is already judging your intent before you tell him to fetch. How Hungarian scientists found this out is explained on PhysOrg. Apparently they track your eyes and read your intentions. Live Science described dog aptitude at about the level of pre-verbal infants, but added this strange Darwinian twist without elaboration: “The study suggests that dogs have evolved to be especially attuned to human communicative signals, and early humans may have selected them for domestication particularly for this reason, the researchers said.” Didn’t dogs evolve long before humans in the evolutionary timeline? Did the humans who selected them use intelligent design or natural selection?
Walk the jog: Why do we find it more comfortable at a certain walking speed to switch to a running gait? Researchers at North Carolina State, publishing in PNAS, (73/pnas.1107972109 PNAS January 4, 2012), found that the calf becomes more efficient when switching to a run at about 4.5 miles per hour. The summary on PhysOrg explains:
The high-speed images revealed that the medial gastrocnemius muscle, a major calf muscle that attaches to the Achilles tendon, can be likened to a “clutch” that engages early in the stride, holding one end of the tendon while the body’s energy is transferred to stretch it. Later, the Achilles – the long, elastic tendon that runs down the back of the lower leg – springs into action by releasing the stored energy in a rapid recoil to help move you.
The study showed that the muscle “speeds up,” or changes its length more and more rapidly as people walk faster and faster, but in doing so provides less and less power. Working harder and providing less power means less overall muscle efficiency.
When people break into a run at about 2 meters per second, however, the study showed that the muscle “slows down,” or changes its length more slowly, providing more power while working less rigorously, thereby increasing its efficiency.
Blood back-talk: How does your body know to produce more blood cells? The blood cells tell the bone marrow, and the marrow talks back. Medical Xpress reported that scientists at UCLA heard the conversation:
In a new study, they show that two-way signaling from two different sets of cells is necessary for bloody-supply balance, both to ensure that enough blood cells are produced to respond to injury and infection and that blood progenitor cells remain available for future needs.
According to the subheading, “this balancing act requires a complex ‘conversation’ involving more parties than originally thought.” Presumably what they found in fruit flies has a counterpart in us humans.
Hang on to your appendix when you can: Bill Parker thinks your appendix could save your life. Interviewed in a guest blog by Rob Dunn on Scientific American, Parker, a professor of surgery, explained that the appendix is not a vestigial organ, but a vital part of the immune system: it “serves as a nature reserve for beneficial bacteria in our guts.” Dunn cited recent evidence that people who have had appendectomies tend to get re-infected more easily.
Amazing recovery: A student at the University of Arizona, in a coma since an October 19 car crash, had been diagnosed with a brain aneurysm and other life-threatening injuries. According to Medical Xpress, his surgeon overruled staff recommendations to take him off life support when surgery was ineffective, and recommended keeping him alive another week. In the St. Nick of time, Sam Schmid woke up, and is now speaking and walking again. “It will be a special Christmas for the family of a 21-year-old University of Arizona student who was nearly taken off life support but is now recovering after waking up from a coma,” the Dec. 23 article said.
If thou thinkest this is wondrous strange,
And therefore as a stranger give it welcome.
There are more things inside thyself, Darwinio,
Than are dreamt of in your philosophy. But come;
Here, as before, never, so help you mercy,
How strange or odd soe’er thou bearest thyself,
As thou perchance hereafter shall think meet
To put an antic explanation on,
That you, at such times observing, never shall,
With arms encumber’d thus, or this headshake,
Or by pronouncing of some doubtful phrase,
As ‘Well, we know it evolved,’ or ‘It emerged or arose,’
Or ‘Natural selection,’ or ‘It might have, perchance,’
Or such ambiguous giving out, to note
That you know naught of anything: this not to do,
So grace and mercy at your most need help you, Swear.