Save lives for under a buck

A previous student of mine showed me this video, which actually ties in with something I had just found out about a few weeks previously. By combining a cheap, paper microscope that cost about $0.50 to make, and a child’s spinning toy, it is possible to diagnose malaria, which kills millions each year. The microscope is called the Foldscope. It’s printed on a heavy piece of die-cut paper, and then gets cut out and folded into a surprisingly powerful microscope, able to see blood cells. You can preorder these yourself (I have!). The other piece, the spinning toy, replaces expensive centrifuges to separate the blood into components. Coupled together (along with a doctor) you can do the lab work for diagnosing malaria for under $1.

Antibacterial dragonflys

There are a number of things that are naturally antibacterial. Silver, for one. For a long time, people have been using silver in things to help stop diseases. There’s also dragonfly wings. Now, scientists are making surfaces similar to the dragonfly wings to destroy bacteria. These are called nano-textured surfaces (NTS) and might lead to new materials that help prevent diseases.

Why you get carsick when reading

Do you get carsick when you try to read in the car? It’s very annoying for someone who really likes to bury their nose in a book. There’s this time in the car going somewhere—maybe a couple of hours. Why waste that time just staring out the window, when you could be reading? But once you start reading, your stomach tells you, in no uncertain terms, that you’re going to be sick soon.

Why?

Well, it has to do with how your body interprets mixed messages. Your vestibular system in the ears is constantly telling your brain that you’re moving. At the same time, your eyes are looking at a book that isn’t moving. These mixed messages tell your brain that something’s wrong. And the only thing that leads to this kind of mixed messages—at least the only thing for many millions of years of evolution—is that you’ve been poisoned. The body’s reaction to thinking that it has swallowed something really nasty is to un-swallow it. You know, throwing up.

This doesn’t affect everyone to the same degree, which is just individual variation. Maybe you have genes that don’t get as upset about this. That’s good if you like reading in the car. But it doesn’t bode well if you inadvertently swallow some poison.

We can now make stems cells from adult cells

Stem cells are the special cells that can turn into any kind of cell in the body. Embryos have them, and use them during development. This has lead to controversy as collecting stem cells needed destroying an embryo. Now we can take cells from an adult, and turn them into pluripotent stem cells by reprogramming them.

This can be done by turning on genes that are active in stem cells, and turning off genes that are active in whatever type of cell they are. Scientists also introduce proteins that are important during embryonic development.

Hopefully this will allow stem cell research in the United States to catch up with the rest of the world.

New spinal cells for rats

Researchers announced this week that they have regrown part of the spinal column of rats. They implanted neural stem cells in the corticospinal tract of rats, and managed to get them to grow as spinal cord cells. The rats gained an increase in motor function (they could move better after the new cells grew). Previous research had tried to do something similar, but this was the first time they got regeneration of spinal cells. This work shows promise for creating new therapies for humans.

“We humans use corticospinal axons for voluntary movement,” said Tuszynski. “In the absence of regeneration of this system in previous studies, I was doubtful that most therapies taken to humans would improve function. Now that we can regenerate the most important motor system for humans, I think that the potential for translation is more promising.”

Preying Mantises can see depth

The preying mantis is an excellent hunter. Does it have depth perception to help it snag insects? It turns out that it does. Scientists put tiny 3D glasses on them and showed them 2D and 3D videos of insects, and they only went for the 3D ones.

The mantis (and we) use eyes that are separated to get binocular vision to get two slightly different perspectives on things. Various cues from the two images and how the eyes line up give us information on how far away things are.

New pre-human transitional fossils found in South Africa

Two years ago, in September 2013, cavers went deep into the Rising Star cave in South Africa. They found fossils of a previously undiscovered ancestor of humans. The new species, Homo naledi, fits into a fossil gap between the Australopithecine, and Homo erectus. The followup expedition found more bone fossils than at any other pre-human site in Africa. They found bones from at least 15 individuals.

Many of the features fell between what you would expect for Australopithecus and Homo: teeth, pelvis, hands, etc. The skulls looked like Homo, but the brain case was a little of half the size of H. erectus’s.

It is difficult to determine how old the fossils are. They weren’t found embedded in rock, which would allow radiometric dating, and are too old for carbon dating. If H. naledi is very old, it could predate Lucy; if young, it would be contemporary with H. erectus. But most likely is that it would fit in just as the Australopithecines and Homo branched, around 2,000,000 years ago.

You can read more at National Geographic, The Atlantic, and the Washington Post.

‘Smart’ mice may one day help people with cognitive problems

By changing a single gene, scientists have made mice that are smarter, and recall fear less. This gene affects how active the enzyme PDE4B is. This enzyme occurs in many vertebrates, including humans.

The “brainy mice” showed a better ability than ordinary mice to recognise another mouse that they had been introduced to the day before. They were also quicker at learning the location of a hidden escape platform in a test called the Morris water maze.

While the enhanced mice were smarter, they also showed less anxiety. This wouldn’t help mice in the wild, as they would be found by predators more easily. These mice spent more time in the open, and aren’t as scared of cat urine.

Researchers hope that medicines that affect PDE4B may someday be used for helping people with Alzheimer’s.