Immune system cells called neutrophils sometimes do much the same: When confronted with bacteria, they unravel and shoot out their chromatin—the tightly wound mix of DNA and proteins that keeps genes packaged in cells. The resulting molecular mesh, known as a neutrophil extracellular trap, or NET, traps and kills bacteria, providing an additional line of defense against bloodstream infections.
Most of us are familiar with “good” and “bad” cholesterol. Low-density lipoprotein (LDL) is “bad” because it keeps cholesterol in the body, while the “goodness” of high-density lipoprotein (HDL) stems from its ability to scoop up old, used cholesterol and escort it to the liver for disposal. Because high levels of HDL in the blood are associated with lower risk of cardiovascular disease (a link that has recently come under question), it has received much attention from researchers.
And anyone who travels a great deal has probably heard about deep vein thrombosis or DVT, often cited as a good reason to get up and stretch your legs on a long flight. Restriction of normal blood flow—whether from being bedridden, paralyzed or sitting for hours on airplanes—is a major cause of blood clots in the legs. Though these clots can be painful in and of themselves, if they break free and travel to the lungs they can cause a potentially fatal pulmonary embolism. In fact, DVTs afflict nearly a million Americans each year and claim a quarter of a million lives.