Extracting brain cells through the nose could cure diabetes

Rats with both type 1 and type 2 diabetes have been completely cured of the disease, using neuronal stem cells that have been modified to produce insulin. This approach should work in humans, too, and all it involves is shoving a needle up your nose into your brain. Yay!
Stem cells are near-universally acknowledged to be the Next Big Thing in medicine, and the only reason that we haven't used them to cure every single disease already is that we can't all agree on a reasonable, ethical place to go get them from. But we've got stem cells all over the place in our own bodies, we just have to go and harvest them, which is easier said than done, but definitely not impossible.
Our brains, for example, are home to neural stem cells, which (with a little prodding) can transform themselves to perform all kinds of helpful tasks. One of these tasks is producing insulin, which researchers at the Institute of Advanced Industrial Science and Technology in Tsukuba Science City, Japan have shown can totally cure type 1 and type 2 diabetes, at least in rats.
To get the stem cells, the researchers stuck a needle up the noses of diabetic rats and poked around in their brains a little bit, extracting tissue from the olfactory bulb and the hippocampus, which are the parts of the brain that allow you to smell things and store memories, so poking them with a big needle is totally not a big deal.
The rat's brain tissue was chock-full of neural stem cells, which were extracted and taught to produce insulin using a human protein called Wnt3a. Then the cells were stuck onto thin sheets of collagen, which were implanted on top of the rat's pancreas, and within a week, the rat no longer had diabetes, as the stem cells were effectively able to produce insulin to regulate blood glucose levels. After 19 weeks, the stem cell sheets were removed, and the rats went straight back to being diabetic, with no other harmful effects.
Apparently, extracting neural stem cells from humans in this manner (i.e. with the needle up the nose) has already been tried and is completely safe, so all that remains is to verify that the neural stem cell insulin education technique works on human stems cell lines as well as in rats, and we could be looking at a permanent, drug-free cure for diabetes.