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First Images of a Heart Injected With Liquid Metal
KentuckyFC writes "The early symptoms of many diseases show up first in the smallest blood vessels, but imaging the fine structure of these vessels is a tricky problem for medics. The most common way is to inject them with a contrast agent and use x-ray tomography to create a 3D image of their structure. This shows problems in the large vessels but not smaller ones. The problem is the lack of contrast. Conventional contrast agents are based on iodine, which has a high electron density and so better absorbs x-rays than other atoms. But a better solution would be to use a higher density fluid, such as a liquid metal. The obvious fears associated with toxicity and so forth mean this has never been tried. Until now. A team of Chinese biomedical engineers have created the world's first images of a pig's heart injected with gallium. This has a melting point of 29 degrees C, so it's a liquid at body temperature. And the results show the detailed structure of the tiniest blood vessels, revealing capillaries just 0.07 mm in diameter. That's significantly more detailed than is possible with iodine-based contrast agents. An important question is whether this technique will ever be possible in humans. The Chinese team seems optimistic. They say gallium is chemically inert, non-toxic to humans and can be injected and sucked out without leaving a residue. 'It suggests the possibility for localized in vivo vascular-enhanced radiological imaging in the near future.'"
"what could possibly go wrong" post
or the "not invented here" post.
I am intrigued. I mean is this the start of the T-1000???
have you seen my sig? there are many others like it but none that are the same
But what if it does leave a residue? And what if that residue - chemically inert, apparently - remains in the body indefinitely? And what if you then go outside in a cold day, and that residue drops below 29 C in your extremities?
At least according to http://theodoregray.com/periodictable/Elements/031/index.s7.html gallium and at least some of its alloys are really sticky, leaving residue on most anything. "Unfortunately, it stains your hands and is hard to get off, so I don't recommend it. In fact, it stains or sticks to just about anything, which is very irritating because it would otherwise make a very nice substitute for mercury where a liquid metal is called for."
I've used one of those gallium-containing fake-mercury thermometers myself, and after a few uses the liquid metal got stuck to the glass tube, and it never worked again. They could have made some better alloy of it or something, but that's not mentioned in the abstract, at least.
(Also, someone is actually using Medium? Impressive, I was compelled to use it for a course, and it was the most dead "social network" I've ever seen.)
any comment on this? i mean, CHICOMs abusing pork?
My eyes! They may need to perform this trick on them to find all the capillaries that just burst...
For large sets, this will be our guide even unto death, for the LORD will work for each type of data it is applied to...
go find sarah con-nor.
and go be Cal-i-fornia gov-nor.
Not surprisingly the improvements here are not just restricted to the visual field. If Gallium provides a lower level detail, it would also reveal lower level heart wall abnormalities that usually requires the patient to be subject to a MUGA scan or resting Thallium study to reveal smaller perfusion defects. These tests can occur post-angiography (heart cath) exposing the patient to more dye increases the rate of kidney failure and kidney malfunction following radionuclide dye procedures. Additionally, this procedure, with blood peptide screening, could lead to even earlier international cardiology - which does things like keeping people out of a cath lab in the first place. Typically the first indication that a cath is in need, is that a heart attack has already happened.
So what happens to the nervous system when exposed to liquid metal? The brain and muscles that work off electrical impulses. Wouldn't liquid metal interfere with this?
Life is not for the lazy.
I want to see more about the pig on whom the experiment was done.
How do they suck the metal back out after it's in every tiny blood vessel of a heart? Maybe most of it stays cohesive enough to suck out in one draw, but surely as blood vessels collapse under the suction, bits and pieces of the liquid metal will break off and remain within the blood vessels. How do they get that metal out?
Does it flow through capillaries?
Having worked with gallium, it is not the easiest metal to work with. It forms oxides easily on its surface, and when these oxides combine with the metal, the metal can stick to metals and glass quite easily. Gallium has been used to back mirrors for that reason.
For those wondering, just because it melts easily, does not mean it has any vapors. Unlike mercury, it has a very high boiling points and has essentially zero vapor pressure at temperatures that can be tolerated by people. As for non-toxic, as far as I know it is not poisonous in reasonable quantities, but neither is it generally recognized as safe (GRAS). Six-nines gallium is probably what to use (99.9999%), as Five-nines gallium (99.999%) usually has signifcant mercury levels in the remaining portion.
It supercools very nicely in plastic containers, and once melted will stay liquid at room temperature for quite a while. It expands upon freezing, like water, and often develops a distinctive cracking pattern when solidifying.
It will eat aluminum instantly. Certain stainless steels are fine for a while, but iron (not plain steel), berylium, tungsten and the like are other metals you can use with it and not have problems with dissolving part of it.
It is a blast, and you can buy small quantities of it from Amazon.
The name is clearly unacceptable. Change it from "gallium" to "freedomium" .
(Yes, you language pedants, that is the origin of the name)
https://app.box.com/WitthoftResume Code: https://github.com/cellocgw
So my mother was an X-Ray technition for 25 years, and was trained in the 70s. In fact, metals, if not this kind of "liquid metal" have not only been tried, but used. In fact, when she was working back in the 90s, she used to say that soft tissue x-rays back in the 50s were much sharper because of the better contrast they had.
Better....because it contained thorium. While it made amazing x-rays, it turned out to not be so good for the patients. Turns out those "harmless" alpha decays are a lot less harmless when they happen inside your body.
I never really looked up the specific contrast before, apparently mom got her decades wrong, but it was history for her too so that isn't too surprizing: http://en.wikipedia.org/wiki/Thorotrast
"I opened my eyes, and everything went dark again"
Is the gallium heart Ig Nobel material or just an element like a golden heart?
Melamine laced pet food and baby formula... Awesome... can't wait to try it!
Brawndo: It's what plants crave!
duh duh duh duh-duh...duh duh duh duh-duh....
That can pass though bio sensor with living tissue
They can't be serious about anything except getting press attention. Gallium is sticky, not all that unreactive, and immiscible with water-based fluids. So, when you inject it, it displaces blood (thus cutting off oxygen to the tissues it perfuses), it gets lodged wherever it goes, and it almost certainly leaches into the surrounding fluids fairly swiftly as chloride ions and oxidizing species attack it. And ionic gallium isn't that non-toxic, as I recall.
Look up "Gallium Scan". It is typically used to help determine if a cancer has metastasized.
You get injected with a gallium solution, and then wait two days while the radioactive ions collect in bones and tissues. When it's time for the scan, you lay on a table that effectively holds a body-sized film. The "scan" involves you laying still for 30 minutes while the film is exposed to your body.
Each time I had this done, I was told to stay away from small children for a week after the procedure.
1) Absorption of the xray beam is not just based on a material's electron density. The contrast media we use today have a k-shell energy in the mid 30 kev which causes a sharp increase in the amount of absorption due to the photoelectric effect proportional to compton scatter. This means they have a higher absorption at these energies than their atomic number would indicate. Gallium's atomic number is lower than iodine's and its k edge is at 10 kev rather than in the 30s. I find it hard to believe that it provides better contrast resolution AT SIMILAR DOSES than iodine based contrast media. The actual paper (http://arxiv.org/ftp/arxiv/papers/1311/1311.6717.pdf) does not discuss the dose of gallium administered but based on the images I would assume they completely filled the coronary vasculature with gallium. This would not be compatible with life.
2) We have administered gallium 67 salts intravenously for medical imaging for decades, although it is out favor these days due to relative inferiority to newer imaging agents such as FDG-F18. Since the isotope is emitting photons out of the patient rather than us shooting photons into the patient and depending on gallium to absorb them, the doses are much lower for the type of imaging currently used than they would have to be for the proposed use as a contrast agent. As described above, completely replacing the blood with gallium to perform conventional or CT angiography would not be compatible with life.
Source: Radiology Society of North America physics modules http://www.rsna.org/RSNA/AAPM_Online_Physics_Modules_.aspx (massive paywall)
They say gallium is chemically inert, non-toxic to humans and can be injected and sucked out without leaving a residue.
Doing even the most cursory of searches on gallium and reading through the Wikipedia entry (http://en.wikipedia.org/wiki/Gallium) would suggest that gallium is not chemically intert, may not be non-toxic to humans, and given that extremities can easily get cold enough to drop below the freezing point of gallium, I'd have to say that it might rather well leave a residue, forget about the stickiness others have reported.
Yea, that'd be great: inject liquid metal, have it thicken and solidify in your feet and fingertips because you step outside on a brisk day, giving you the equivalent of massive frostbite. No thank you.
There are growing numbers of Chinese researchers in my field (neuroscience) and their results always need to be taken with an extra-large grain of salt. It looks like the same is true here.
Put my fist through my alarm clock with its ding-dong death inside my ear. - The Blackjacks.
Oh wait... this is Slashdot. Nobody here is capable of feeling the suffering of others.You're all so 'grown up'!
So... can ANY of you psychopaths imagine what it's like to be tortured to death like this?
That's an unusual choice.I would have used Mercury, or hot molten lead.
When we can trust the Chinese to not use lead in children's toys I think we should take a look at this gallium thing.
quiquid id est, timeo puellas et oscula dantes.
It's not for X-rays, but rather they inject something containing Tc-99m (metastable isomer of Tc-99) then run a scanner to detect the gamma rays given off -- so you get irradiated from the inside rather than the outside. It's got a half-life (to Tc-99) of about 6 hours, and you pee out the compound. Usually combined with a stress test for before/after images.
I've had it a couple of times, but alas I'm still not showing any super-powers from the gamma exposure.
How long before these turn up in the food supply? Just sayin'...
Just think of all the Falun Gong- er, I mean, "drug addicts" who will benefit from the experiments! Reminds me of the good ole' days of WWII Japan's Unit 731 vivisections! Yee haw! Cut 'em up, cowboys!
Always get the regeneration/healing power before you get the claws.
Wonder what other elements they tried that failed.
I'm relatively new to the cath lab, but Iodine-containing agents typically get the job done as far as diagnosing coronary blockages. In my lab, we do nuclear scan for evaluating perfusion even before we decide to do an angiogram (albeit we sometimes do it anyway, but that becomes an insurance battle). A worthwhile advantage would be lower risk of renal failure (not mentioned in the article). While few patients with healthy or even mediocre kidneys end up having problems, it's always a concern with those of less renal function and will sometimes mean not doing an elective cath.
Chewbacon
The Bible is like Wikipedia: written by a bunch of people and verifiable by questionable sources.
The entry for "Alpha Particles" was updated from "Harmless." to "Mostly Harmless." quite some time ago. Because it is... AS LONG AS the emitter is *OUTSIDE* the body.
An alpha particle is going to steal electrons from the first molecule it comes in contact with, and become a helium atom. If you're exposed to alpha radiation from the outside, it's going to hit and react with the layer of already dead skin cells called the epidermis.
So yes, as long as you don't swallow, inhale, inject, or otherwise insert the alpha-emitting radioisotope, you're probably going to be just fine.