Tapeworms inside the human brain

Most of us have heard of tapeworms, the parasitic creatures that find their way into the human digestive system, and can grow very long indeed. They can cause quite a bit of trouble, but I had no idea how extreme the trouble can sometimes be.

Theodore Nash sees only a few dozen patients a year in his clinic at the National Institutes of Health in Bethesda, Maryland. That’s pretty small as medical practices go, but what his patients lack in number they make up for in the intensity of their symptoms. Some fall into comas. Some are paralyzed down one side of their body. Others can’t walk a straight line. Still others come to Nash partially blind, or with so much fluid in their brain that they need shunts implanted to relieve the pressure. Some lose the ability to speak; many fall into violent seizures.

Underneath this panoply of symptoms is the same cause, captured in the MRI scans that Nash takes of his patients’ brains. Each brain contains one or more whitish blobs. You might guess that these are tumors. But Nash knows the blobs are not made of the patient’s own cells. They are tapeworms. Aliens.

This is scary—they can find their way into the bloodstream, and in the human brain, where they happily live and grow as cysts.

Well, let’s back up a bit. I didn’t know that the tape worm life cycle involves humans and pigs, and that the normal life cycle can only be completed via undercooked pig meat. There you go, I thought, that’s why you should avoid undercooked meat.

But—no. That’s not the half of it.

The more serious trouble (of the brain cyst kind) happens when the normal tapeworm cycle is disrupted. Instead of finding their way inside a pig, tapeworm eggs sometimes find their way straight back inside humans, and the confused eggs behave as they would in a pig—reach for the blood stream. And that’s the recipe for disaster. You could be having tapeworm cysts in your brain, without ever having had raw or undercooked meat.

I won’t give everything away; go read the whole article. It’s excellent, informative, and as I said, a little scary.


Some birds have their own HUDs

This is an amazing discovery. It’s been known, of course, that some birds (and other animals) are capable of detecting the earth’s magnetic field. This is what gives them a sense of direction, and they seem to know exactly where they are going. Until now, exactly how this detection happened was not completely known, although it was guessed that vision was involved.

Here’s the latest:

This ‘compass’ sense must be associated with the eyeball, because the birds cannot detect magnetic fields in darkness.

But now Oxford University and National University of Singapore scientists have shown that birds may really ‘see’ the invisible force of magnetism, giving them a compass on top of their normal vision: rather like aircraft ‘head up displays’ which overlay crucial navigation information on a transparent screen in front of the pilot.

The ‘technology’, so to speak, involves a special molecule in the eye. When a photon of light enters the eye and hits the molecule, it causes an electromagnetic effect in the eye—and since this effect also depends on the surrounding magnetic field, the effect translates into a ‘map’ of the earth’s magnetic field. All this, right in the eye of the bird!

The next question, I guess, ought to be: is the absence of light the only reason that the birds can’t navigate at night? Would they do fine if there was artificial ambient light at night? What happens if they are fitted out with a ‘headlamp’ of sorts, that reflects light back into their retinas? Is there a minimum amount of light that would be the threshold? This is all very exciting.

In related news, a protein in the human retina has previously been found to possess magnetic properties. This is possibly remnants of the same system—which poses the question: did humans ever have the capacity to detect magnetic fields? Is this a rudimentary evolutionary leftover, or did we shed our sensing capabilities as we gave up our migratory habits and settled down to a life of agriculture?

Really—the more we find out about nature, the more amazing it all is. (Well, granted—the Earth has had a few million years to test and improve new technology, but you’ve got to admit, this is pretty cool.)


➶ Of the brain-eating amoeba

Be careful what you do with your tap water:

The Louisiana Department of Health and Hospitals has issued a weird warning: if you have to irrigate your sinuses with water for some medical reason, don’t use tap water. The reason: your brains may get eaten by the Naegleria fowleri.

Water that you drink is quite all right—even if it contains the bacteria, it will be destroyed when it reaches the stomach and the body’s digestive juices.

But beware if you intend to put water up your nose! This channel is not intended for water (or other food), and does not have the same defense systems as our digestive system does.

The amoeba attacks your nervous system, and can pretty soon leave you dead! Fortunately, the way around is pretty simple: just boil the water to kill the bug!

(My gripe with the article: no source information! No links, whatsoever. Terrible.)

∞

➶ The rat that’s ‘immune’ to acid

This is a very interesting article about why the naked mole rat can’t feel pain from acid burns. Apparently it was already known that they don’t feel the pain; their hypothesis about why it happened—that the acid sensing ion channels that tell neurons to transmit pain would be missing—was not true.

Because it turns out that mole rats — despite being the only known vertebrates that are insensitive to the painful stimulus of acid — have the same two fully-functional, acid-sensing channels regulating their pain receptors as the rest of us, and even produce the channels in similar quantities. And this is where things get interesting.

Now they know the actual reason. There’s another way neuron-firing can be controlled, and it is this (sodium) channel that is highly inhibited in the naked rat mole. Similar phenomenons are observed in humans too:

Furthermore — and this doesn’t happen often — humans lacking the Nav1.7 channel have been known to feel no pain whatsoever.

Very interesting, yes, but my question is this: the naked rat mole is insensitive to pain due to acids; but does that mean that it is in fact unaffected by acids? It does not seem so—the phenomenon is purely neurological, and there seems to be nothing physiological that would protect the rat against acids.

Does this not make this a counterproductive adaptation? Why would this adaptation survive? Is it because the natural environments of these rats are entirely devoid of harmful acids, thus making that pain sensation redundant? (Is this also why they’re “naked”, rather than furry?)

Intriguing.

∞

Trying to be too clean

Being conscious of our hygiene is a good thing, of course. But is it possible to overdo our hygiene routines for our own good? Have you noticed how more and more people use sanitizing hand wipes, or antibacterial hand soaps? Their function, of course, is to ‘wipe out’ all the bacteria around you—but is that always a good thing?

I’ve always had my theories, but now there’s actual evidence—it’s probably not a very good thing on the long run.

For one, not all micro-organisms that we’re exposed to (or that live on or inside us) are harmful for our health. Some are actually our friends! It’d suck to have them die out, right? Well, guess what the antimicrobial lotions that you use do.

For another, our bodies have their own incredible immune system, which is trusted with protecting the body against disease, and killing germs and tumors that affect us. Well, part of how the human immune system works is that it’s adaptive, which means, our body actually learns from experience whether a certain organism is harmful or not, and whether something in our body needs to be attacked or not. This is an incredible mechanism, but this, by definition, is dependent upon the body being exposed to some amount of microbes, so that it can keep itself healthy and at a cutting edge.

In fact, this is exactly the function of vaccines: expose the body to a small amount of impotent germs, so that the body can trigger its immune system and form a ‘memory’ of that particular disease. Next time an actual disease tries to attack—BAM!—the immune system is there to take care of it at the outset.

(As an aside, yes—all those people going on an on about getting rid of vaccines? They don’t know what they’re talking about. Some people are not in a position to make an informed choice on their own, and those that are, sometimes make their decisions based on something other than logic, science and information. For example, this (a video on the page starts autoplaying; please mute your speakers if that’s a problem).)

Given this mechanism, what do you think happens when you wipe out every kind of microbe on or around us, with those antimicrobial wipes of yours? The body loses all ability to adapt and keep its immune system updated and at peak working condition. This is fine as long as you allow nothing infectious to approach us—but the moment something does sneak through, the body has no mechanism to counter it. The effect—being sick at the first sign of disease. This, of course, is not such a great thing.

Most people are familiar with this effect—this is why we’re wary about drinking tap water when we visit a new place. Even though residents there are perfectly healthy—which means the water is nominally clean—we might get an upset stomach upon drinking the local water: our bodies were not ready for the local microbial action!

This effect is multiplied many times when we’re chronically using wipes to “sanitize” ourselves. Sanitize ourselves we do, but we also take the edge out of our immune systems.

Being hygienic is good, yes. But it’s also good to play in the mud sometimes, and to expose ourselves to our fellow invisible Earthlings. And it’s mostly fine—and in fact healthier—to wash ourselves with just good old soap!