Human Body Marvels You Probably Don’t Know About

Here’s news of interest to everyone who inhabits a human body. Space aliens, eat your heart out.

Human skin suppresses inflammation after exposure to ultraviolet radiation (Medical Xpress). Your skin automatically knows that too much light might cause inflammation, so it suppresses the inflammation response, and remembers the exposure for days afterward. Not even scientists knew this. A researcher at NIHR Manchester Biomedical Research Centre took volunteers and exposed a portion of skin on their arms to UV radiation (UVR), then examined the skin cells. What he found challenged current thinking.

“Essentially, the cells responsible for helping the skin get back to normal after it is exposed to UVR remain there for around two weeks; they could be there to prevent abnormal skin growth, or potentially to act as ‘gatekeepers’ against further inflammation.

“While we have known why skin becomes inflamed after being exposed to UVR for some time—particularly through sun exposure and sunburn—what the skin does to resolve this and how it adapts in the longer-term has been unknown until now.“

Research reveals the lipid gradient that keeps your eyes wet (Medical Xpress). This discovery comes from Hokkaido University in Japan. Tears keep the corneas of our eyes moist without our conscious thought. Did you know that there are two layers of lipids (fat molecules) between the cornea and the moist liquid of tears? The researchers found out what happens when one of the genes for those lipids (a gene for lipid OAHFA) is turned off in rats: they got dry-eye disease and their corneas suffered damage. It was a crying shame.

The mice were found to have damaged corneas and unstable tear films, both indicative of dry eyes. Further analyses showed that these mice were lacking OAHFAs and their derivatives in their tear films. Interestingly, the scientists also discovered that the OAHFA derivatives have polarities intermediate between OAHFAs and other lipids in the tear film. This strongly suggests that those lipids together form a polarity gradient that plays an important role in connecting the tear film’s inner liquid layer and outer lipid layer, helping the film spread uniformly over the surface of the eye.

Brown fat can burn energy in an unexpected way (Medical Xpress). White fat bad; brown fat good. That’s the rule of thumb. Brown fat burns energy, but white fat stores it. How can we up the brown, and down the white?

When we are exposed to sufficient cold or exercise, small clusters of brown fat cells in our bodies begin to burn up energy. Since 2009, when researchers at Joslin Diabetes Center and other institutions discovered that this helpful form of fat can be active in adults, scientists have sought to turn up the heat from these cells to treat obesity, diabetes and other metabolic conditions….

Mitochondrion structure

The researchers focused on a protein in the mitochondria, UCP1, that activates brown fat burning. When we are exposed to sufficient cold or exercise, small clusters of brown fat cells in our bodies begin to burn up energy. Since 2009, when researchers at Joslin Diabetes Center and other institutions discovered that this helpful form of fat can be active in adults, scientists have sought to turn up the heat from these cells to treat obesity, diabetes and other metabolic conditions.

Lead researcher Yu-Hua Tseng had to comb through 5,000 proteins to find out which ones turn up UCP1. She found two fibroblast growth factors, proteins called FGF6 and FGF9, but was surprised how they acted. It turns out that FGF6 responds to exercise, and FGF9 responds to cold. Can scientists use this discovery to make a pill that will help burn the bad fat and reduce obesity? Time will tell.

The human body as an electrical conductor, a new method of wireless power transfer (Medical Xpress). Our bodies conduct electricity! That should not be a shock to anyone who has touched a Van de Graaf Generator and seen his or her hair rise. German researchers are using that property to power implants without batteries to help activate paralyzed muscles. They only need to produce a milliwatt of power at 5 Hz, safe enough to not cause harm to the body. Little implants 1 cm by 1 mm would work, with the help of the body’s own conductivity.

Coordination amongst quadriceps muscles suggests neural regulation of internal joint stresses, not simplification of task performance (PNAS). This paper sheds new light on the big quad muscles of the thighs. Basically, those muscles are a lot more complex than thought, and rely more on nerves than thought.

Our study overturns a common hypothesis about how the nervous system produces movement. According to this hypothesis, muscles with complementary contributions to overt task performance (e.g., similar joint torques and endpoint forces) are controlled as a single functional unit, often referred to as a “muscle synergy,” and so the activation of muscles with similar task-related actions should strongly covary. Our results do not support this hypothesis and, instead, suggest that covariation patterns amongst muscles better reflect the control of low-level aspects of limb mechanics, such as the stresses and strains within joints. In addition to arguing against this standard interpretation of muscle covariation patterns, our experiments also highlight the critical role of the nervous system in regulating internal joint mechanics.

Woman’s transplanted ‘man hands’ became lighter and more feminine over time (Live Science). Strange but true: a woman in India lost her forearms in an accident in 2016. The only human hands available for transplant were from a 21-year-old man who had just died in a bicycle crash. “I am the first female in the world to have male hands,” Shreya Siddanagowder exclaimed. She was self-conscious of the odd-looking mismatch for a teenage woman, but to her surprise, they started becoming leaner and looking more feminine over time. Even the skin color lightened to match her own.

First glimpse of body’s steering wheel joint sparks hope (University of Portsmouth). Trivia question: what is your body’s “steering wheel joint”? Answer: the subtalar joint in the foot.

The bones of the foot are unique in that they need to be both be extremely flexible allowing the foot to point, twist and flex, but in other positions they need to be absolutely rigid, such as pushing off or jumping so the person doesn’t sprain their ankle.

The key to this ability is the subtalar joint, below the ankle, which until now, doctors couldn’t see rotating while standing.

Using a combination of 3D imaging (computed tomography) and digital volume correlation, the researchers were able to produce images of this joint while load bearing in three different standing positions. They hope the images will allow surgeons to fine-tune prosthetics for people with foot joint problems, like they can do for knee and hip joints. But it will be a challenge, because the foot is very complex.

“No one has ever been able to replace this complex joint. This new research helps us to better understand the complex biomechanics of the foot and could pave the way for new treatments that just aren’t currently available.”

Thank God for your feet – they didn’t just happen! (graphic by DFC)