Creative Minds: Interrogating a Master of Disguise

Monica Mugnier

Monica Mugnier

When I volunteered several years ago as a physician in a small hospital in West Africa, one of the most frustrating and frightening diseases I saw was sleeping sickness. Now, an investigator supported by the NIH Common Fund aims to figure out how this disease pathogen manages to evade the human immune system.

Monica Mugnier’s fascination with parasites started in college when she picked up the book Parasite Rex, a riveting, firsthand account of how “sneaky” parasites can be. The next year, while studying abroad in England, Mugnier met a researcher who had studied one of the most devious of parasites—a protozoan, spread by blood-sucking tsetse flies, that causes sleeping sickness in humans and livestock across sub-Saharan Africa.

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How Sleep Resets the Brain

dendrites

Caption: Colorized 3D reconstruction of dendrites. Neurons receive input from other neurons through synapses, most of which are located along the dendrites on tiny projections called spines.
Credit: The Center for Sleep and Consciousness, University of Wisconsin-Madison School of Medicine

People spend about a third of their lives asleep. When we get too little shut-eye, it takes a toll on attention, learning and memory, not to mention our physical health. Virtually all animals with complex brains seem to have this same need for sleep. But exactly what is it about sleep that’s so essential?

Two NIH-funded studies in mice now offer a possible answer. The two research teams used entirely different approaches to reach the same conclusion: the brain’s neural connections grow stronger during waking hours, but scale back during snooze time. This sleep-related phenomenon apparently keeps neural circuits from overloading, ensuring that mice (and, quite likely humans) awaken with brains that are refreshed and ready to tackle new challenges.

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Cool Videos: Starring the Wiring Diagram of the Human Brain

MRI videoThe human brain contains distinct geographic regions that communicate throughout the day to process information, such as remembering a neighbor’s name or deciding which road to take to work. Key to such processing is a vast network of densely bundled nerve fibers called tracts. It’s estimated that there are thousands of these tracts, and, because the human brain is so tightly packed with cells, they often travel winding, contorted paths to form their critical connections. That situation has previously been difficult for researchers to image three-dimensional tracts in the brain of a living person.

That’s now changing with a new approach called tractography, which is shown with the 3D data visualization technique featured in this video. Here, researchers zoom in and visualize some of the neural connections detected with tractography that originate or terminate near the hippocampus, which is a region of the brain essential to learning and memory. If you’re wondering about what the various colors represent, they indicate a tract’s orientation within the brain: side to side is red, front to back is green, and top to bottom is blue.

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Snapshots of Life: Picturing the Developing Windpipe

Mouse trachea

Randee Young and Xin Sun, University of Wisconsin–Madison

The image above shows a small section of the trachea, or windpipe, of a developing mouse. Although it’s only about the diameter of a pinhead at this stage of development, the mouse trachea has a lot in common structurally with the much wider and longer human trachea. Both develop from a precisely engineered balance between the flexibility of smooth muscle and the supportive strength and durability of cartilage.

Here you can catch a glimpse of this balance. C-rings of cartilage (red) wrap around the back of the trachea, providing the support needed to keep its tube open during breathing. Attached to the ends of the rings are dark shadowy bands of smooth muscles, which are connected to a web of nerves (green). The tension supplied by the muscle cells is essential for proper development of those neatly organized cartilage rings.

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Are E-cigarettes Leading More Kids to Smoke?

Cigarettes vs. E-Cigarettes

Thinkstock\MilknCoffee

Today, thanks to decades of educational efforts about the serious health consequences of inhaled tobacco, fewer young people than ever smoke cigarettes in the United States. So, it’s interesting that a growing of number of middle and high school kids are using e-cigarettes—electronic devices that vaporize flavored liquid that generally contains nicotine.

E-cigarettes come with their own health risks, including lung inflammation, asthma, and respiratory infections. But their supporters argue that “vaping,” as it’s often called, might provide an option that would help young people steer clear of traditional cigarettes and the attendant future risks of lung cancer, emphysema, heart disease, and other serious health conditions. Now, a new NIH-funded study finds that this is—pardon the pun—mostly a pipe dream.

Analyzing the self-reported smoking behaviors of thousands of schoolkids nationwide, researchers found no evidence that the availability of e-cigarettes has served to accelerate the decline in youth smoking. In fact, the researchers concluded the opposite: the popularity of e-cigarettes has led more kids—not fewer—to get hooked on nicotine, which meets all criteria for being an addictive substance.

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