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Medicine Science

Suspended Animation In Mice Without Freezing 147

Predictions Market writes "Low doses of hydrogen sulfide, the toxic gas responsible for the unpleasant odor of rotten eggs, can safely and reversibly depress both metabolism and aspects of cardiovascular function in mice, producing a suspended-animation-like state that does not depend on a reduction in body temperature and include a substantial decrease in heart rate without a drop in blood pressure. The researchers measured factors such as heart rate, blood pressure, body temperature, respiration, and physical activity in normal mice exposed to low-dose (80 ppm) hydrogen sulfide for several hours. In all the mice, metabolic measurements such as consumption of oxygen and production of carbon dioxide dropped in as little as 10 minutes after they began inhaling hydrogen sulfide, remained low as long as the gas was administered, and returned to normal within 30 minutes of the resumption of a normal air supply. 'Producing a reversible hypometabolic state could allow organ function to be preserved when oxygen supply is limited, such as after a traumatic injury,' says the lead author of the study. 'We don't know yet if these results will be transferable to humans, so our next step will be to study the use of hydrogen sulfide in larger mammals.' The full report is available online."
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Suspended Animation In Mice Without Freezing

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  • Yeah but... (Score:5, Funny)

    by Xyde ( 415798 ) <slashdot@pur3.14rrr.net minus pi> on Wednesday March 26, 2008 @04:35AM (#22867294)
    after inhaling hydrogen sulfide for 30 minutes, trust me, you'll wish you were dead.
    • True but... (Score:5, Insightful)

      by Sterrance ( 1257342 ) on Wednesday March 26, 2008 @04:48AM (#22867326)
      many things that can save our lives (major surgery, chemotherapy) also leaves us wanting to die. Just because something is horribly painful doesn't mean we should avoid it.
      • by $RANDOMLUSER ( 804576 ) on Wednesday March 26, 2008 @05:29AM (#22867476)
        I'm suddenly beginning to realize why married men live longer...
        • Re: (Score:2, Funny)

          by MalHavoc ( 590724 )
          Suspended animation because of hydrogen sulfide? This is probably why I feel sleepy after letting a big one rip in my office.
      • Just because something is horribly painful doesn't mean we should avoid it.
        Words to live by, if ever there were!

        But seriously... H2S is a highly poisonous gas, so I would heartily recommend avoiding it whenever you have the option. Fortunately we can smell it at concentrations far below what it takes to do us harm in a brief exposure.
      • I could make the case against it.

        Imagine you're 80+ years old, and given the option of living 2 years on chemo, or one without.

        Would you be willing to live in pain, and as a major burden to society and your family in exchange for an extra year, especially at such an advanced age?

        I'm not one of those odd folk who refuse all sorts of medical treatment, although once a certain point is reached, you're only (barely) prolonging the inevitable.
        • by Eddi3 ( 1046882 )
          Um, technically, isn't using any sort of medical treatment prolonging the inevitable? We're all going to die eventually.

          A year might be worth it.
        • by iamacat ( 583406 )
          Why should I live in pain if there are effective drugs to manage the condition? I will do the chemo and then take enough morphine and ecstasy to be pain free and happy.
      • Imagine the weaponization or equivalent use of this gas to bring ground wars to a state of...

        suspension... and the characters probably WILL become... animated... But, I fear the doses required to suspend the animated warriors may be strong enough to ruin seals on masks, and possibly just burn up the lungs.

        Gives new meaning to "compulsory expulsion"...
    • Those poor mice.
    • I understand how this can induce hibernation is some mammals. all they have to do is eat much of starchy gas producing foods and then fart in their winter nests underground. this puts them to sleep
    • Re:Yeah but... (Score:5, Informative)

      by Cyberax ( 705495 ) on Wednesday March 26, 2008 @06:51AM (#22867788)
      Actually, no. Your nose will be almost completely anaesthetized after several breaths.

      That's actually a dangerous feature of hydrogen sulfide - it's quite poisonous and you can breath a fatal dose of it without even realizing that you're breathing a poison.
    • by hughk ( 248126 )
      Anhydrous H2S is nearly odourless (until it starts mixing with atmospheric moisture). It will kill in a lot less than thirty minutes and, I believe has done (chemical plant accidents).
      • Re:Yeah but... (Score:4, Informative)

        by Teun ( 17872 ) on Wednesday March 26, 2008 @09:25AM (#22868992)
        The safe level to work in for 8 hours per day (MAC value), 5 days per week has recently been dropped from 10 ppm to 2 ppm.
        80 ppm of H2S is going to be lethal after 8 -24 hrs of exposure, much earlier you will be suffering bleeding and other very unpleasant effects.
        At 500 ppm you're dead in 30 to 60 minutes and at 800 ppm you will not survive 2 minutes.
        The kicker is at 1000 ppm, you're immediately unconscious and will die within seconds.

        You'll start smelling it at about 0.1 ppm but at otherwise not lethal concentrations it will desensitise your nose and you will eventually not realise it's still around or getting stronger.

        As a side effect it has a much wider range of explosiveness than regular hydrocarbon gasses and because it's heavier than air it will concentrate at low places.
        • by hughk ( 248126 )

          Many, many years ago before I moved into the 'safer' world of banking, I was involved with plat supervisory and management systems at a Petrochemical company. We often had to visit plant control rooms, which meant being uncomfortably close to the plant itself. It was always a favourite thing of the plant engineers to relate to us IT people how dangerous the stuff sitting in the plant was.

          Given the fact that all plants leak over time, it was always one of the more interesting calls that a plant manager ha

      • by sjames ( 1099 )

        H2S is toxic in larger amounts and has no effect at all in smaller amounts, much like anything else. Any gases used in anaesthesia will be lethal if the concentration is too high for too long.

  • by n3tcat ( 664243 ) on Wednesday March 26, 2008 @04:39AM (#22867308)
    We can clone mice. We can cure mice cancer. We can put them into suspended animation, allowing them to live on into future generations (meaning they will probably be the first organic space pets). Something tells me that the rats of NIMH are already in the execution phase of some higher level plans with all the work we've managed to accomplish on their genetics.
  • by cheros ( 223479 ) on Wednesday March 26, 2008 @04:42AM (#22867316)
    Premature pressure loss can result in a whole room full of people in suspended animation.

    "All I can remember was this overpowering stink" .. :-)
  • by QuantumG ( 50515 ) * <qg@biodome.org> on Wednesday March 26, 2008 @04:45AM (#22867318) Homepage Journal

    'We don't know yet if these results will be transferable to humans, so our next step will be to study the use of hydrogen sulfide in larger mammals.'
    Uhh, no. The next step is to determine if this is the kind of suspended animation that is good for anything. If the mice enter a reduced metabolic state and then, after 3 days, die, well that's not terribly useful for anything. If, however, the mice managed to live 10 times the usual rodent lifetime then that's something... not terribly great.. but something. Try to make it so the mice are recoverable after 1000x the usual lifespan and you might have something useful.
    • by Moraelin ( 679338 ) on Wednesday March 26, 2008 @05:00AM (#22867358) Journal
      While that's insightful in its own right, from reading the summary, I get the impression that they're not aiming for the kind of suspended animation where you freeze someone for 1000 years and wake them up later. Doing that at room temperature would be kinda dangerous anyway, since if you slowed their immune system 10 times they'll rot alive sooner or later anyway.

      I'm getting the impression that this is more for rushing you to a hospital when they picked you up half-dead and bled half-dry off the side of the road.

      If you're in serious shock for example, if the other mechanisms still work, the body will try to keep the brain alive, even at the cost of cutting off oxygen supply to the other internal organs. Which decay very fast. (Muscles have their own oxygen reserves, so they tend to survive, your liver doesn't.) Cells run out of oxygen and essentially commit suicide in an orderly fashion, i.e., apoptosis [wikipedia.org].

      If it doesn't have enough even for the brain, which is often the case, the damage is irreversible and often fatal. Very fast.

      So if they can slow your metabolism a lot, that might just give them extra time to haul you into ER. It might just turn that 5 minute rush before your brain starts getting massive damage, into, say, 50 minutes. Which might just do the trick.

      I.e., briefly: it's not for colonizing Alpha Centauri, mate, it's just while they haul you to ER.
      • While that's insightful in its own right, from reading the summary, I get the impression that they're not aiming for the kind of suspended animation where you freeze someone for 1000 years and wake them up later.

        Not many people can afford that much Somec.
      • it's not for colonizing Alpha Centauri, mate, it's just while they haul you to ER.


        Is there any reason this can't be combined with other methods to make some form of hibernation a reality?
        • Well, I suppose they could stuff you full of this gas _and_ freeze you. I guess it just makes sense to solve it one step at a time anyway. It's probably enough work to find out what it does to a human and get it through FDA even at room temperature. They'll have time to worry about the freezing part after they get that sorted out.
          • Re: (Score:3, Informative)

            by hitmark ( 640295 )
            the problem is that the freezing creates ice, sharp ice...

            still, sugar helps here i think...
            • Hmm... anyone else suddenly crave a margarita?
            • by Abreu ( 173023 )
              In the Vorkosigan saga (I know, not hard sci-fi) soldiers can be frozen after grave injuries and revived later in a hospital.

              However, in order to do this, they must be completely exsanguinated and the blood replaced by a glycol compound (sorta like antifreeze). This way, the organs are mostly protected from damage by ice crystals...

              However, the process is not 100% guaranteed, as people can not always be saved this way and even when the subject is correctly prepared, there is the risk of brain damage.
              • Re: (Score:3, Interesting)

                by AJWM ( 19027 )
                In the Vorkosigan saga (I know, not hard sci-fi)

                I'd say that the Vorkosigan stories are harder sci-fi than most. Sure, you've got to allow Bujold faster-than-light travel/communications, but everything else is pretty consistent. It's a far cry from space opera, even if it doesn't have rivets. A lot of her stories revolve (indirectly) around biology, and there she's on pretty solid (if speculative) ground.

                If you want to restrict "hard" sci-fi to stuff that doesn't break any laws of physics (or any other
                • by Abreu ( 173023 )
                  I agree wholeheartedly, which is why I don't really read much "Mundane SF".

                  Just a small correction on Bujold: In the Vorkosigan books, there is no faster than light communications, only travel (via wormholes)

                  Several communication satelites move in and out of wormholes to transmit data between worlds, which results on long lag times and sometimes in total denial of service, in case of wars
                  • by AJWM ( 19027 )
                    You're right, my bad. It's been a while since I read a Vorkosigan, Bujold isn't writing enough of them ;-)
            • Very much so, indeed. Which is why I called it a problem to be solved, maybe in a future step.
            • the problem is that the freezing creates ice, sharp ice...

              Very good point. This is why cryonic suspension efforts typically involve displacing as much water as possible with a cryoprotective (usually glycerol-based) solution before reaching the freezing point. This minimizes ice crystal formation, which is very much a Good Thing.

              The current state-of-the-art in cryonic suspension involves using a vitrifying solution that never actually freezes at all, but instead becomes glass-like. There are still technical
        • It made a man sleep for 500 years and emerge in the same state in which he went in, and that was gas only.

          At least that's how it happened in the original Buck Rogers story. He was in a mine and exposed to gas that put him to sleep and he awoke 500 years later.
      • by nten ( 709128 ) on Wednesday March 26, 2008 @06:43AM (#22867752)
        I read recently (on /. I think) that it was discovered the tissue damage was done when RISING o2 levels triggered apoptosis. Meaning there is actually a period as long as 2hrs where little or no tissue damage has occurred. If the o2 levels can be brought up in a way that keeps the trigger from thinking a massive o2 spike is about to mutate all the DNA we might realize the dream of Herbert West. I also read about this a while back and they didn't think it would scale to humans, but if it did, it might stack nicely to allow delaying reanimation even longer.
        • Iron and Apoptosis (Score:2, Informative)

          by francisstp ( 1137345 )
          Yes, and iron is a big factor in this process apparently. When oxygen-filled blood finally reaches the damaged tissues, the liberated iron acts as a super free-radical and wreaks havoc.


          I think the article you're referring to is http://www.newsweek.com/id/35045 [newsweek.com]
        • by sjames ( 1099 )

          I read recently (on /. I think) that it was discovered the tissue damage was done when RISING o2 levels triggered apoptosis.

          While I'm not a doctor, I see potential in that. IIRC, the apoptosis is triggered by the mitochondria which are damped down by the H2S. It might be just the thing to allow re-perfusion and have the mitochondria resume metabolism in an orderly fashion without the massive cell death.

      • Re: (Score:2, Interesting)

        by sckeener ( 137243 )
        it's not for colonizing Alpha Centauri, mate, it's just while they haul you to ER.

        Baby steps...lets sleep to mars and then look to Alpha Centauri.

        Keep the bodies cold (not freezing) and let them sleep the entire way to Mars.

        Hook them up to a vitamin packed IV, so they don't starve. Even at their slowed rate, two years is a long time.

        Admittedly we might just do periodic wake ups so they can eat, stretch their muscles, and send status reports. The rate would just depend on the safety margin of the hibernati
        • Well, considering "stretch some muscles", they'll have to take some newly codified law books with them, redefining sexual misdemeanors.

          "The more I miss it, de meaner i get" is what some might say. I guess it might separate the men from the mice, the asTROnaughts from assholenauts and the a*holenaughts...

          Now, if necrosis or other tissue damage happens to the reproductive organs (why would they be different? Well, has anyone studied the effects of N2S on sperm count? Ovarian production?), colonization of dist
      • it's not for colonizing Alpha Centauri, mate, it's just while they haul you to ER

        Although considering the current perception in the medical community of EMTs and Paramedics, it's very unlikely this will ever come to pass. Most Ambulances are BLS (basic life support) trucks with, at best, and EMT-Intermediate (or state equivalent) who in most jurisdictions can't hang a normal saline drip without begging medical direction. Perhaps they'd eventually allow paramedics on ALS rigs (often dispatched after a BLS rig has been on scene for a few minutes) to do something like this since it's v

      • by sjames ( 1099 )

        As far as sci-fi style suspended animation, this isn't quite it. It will significantly reduce but not by any means stop metabolism. It could potentially be useful for months in space to reduce resources required, but certainly nothing like the frozen for 1000 years scenerio.

        Medical uses are more likely. In addition to the emergency use you point out, it could also be useful for surgical procedures that aren't considered survivable today or perhaps to avoid some of the potential nasty effects of ECMO in a

      • by Z34107 ( 925136 )

        According to the Wikipedia entry on Hydrogen Sulfide, scientists did a study on mice in 2005 that came to the same conclusions as the summary. I hope this article isn't that old.

        But, even more interestingly, good ol' Wikipedia links to a study [pccmjournal.com] done in 2008 on larger mammals (pigs). They could not reproduce the "suspended animation" effect - in fact, it seemed to do the opposite.

        So - I guess no H2S administered in ambulances any time soon.

      • lications...

        i was going to ask "Are there any "StraTactical" uses/applications of this?"

        But, then i think i probably have to answer my own question with:

        1. deep-sea sleds-delivered divers or swimmers might get gas and the bends on delivery
        2. what would be the weight tradeoff in sleds vs rebreathing units?
        3. what kind of missions might need divers to be suspended?
        4. would this enable submarine crews trapped at say 3,000 feet to hibernate until rescued?
        5. could this be weaponized and used to attack ships even
    • by Smordnys s'regrepsA ( 1160895 ) on Wednesday March 26, 2008 @05:05AM (#22867376) Journal
      There are always places where harmful chemicals can be useful. Even if this causes damage/death after a few days/weeks/months, there are situations where it will prevent death that would occur in minutes.

      Just off the top of my head, mines. Mandatory pressurized bottle w/ masks at every junction in a mine, in case of collapse (I'm thinking it *has* to be less explosive than storing bottles of pure oxygen). If it slows oxygen consumption to 25% (pulled out of my ass, because examples need numbers!) of normal, that gives rescue workers 4 times a long to dig out live bodies.

      Once they are out, the hospitals/trained medical professionals can go about treating them for Crush Syndrome and for the poison that kept them alive by killing them slowly.
      • Assuming you can hit the right amount of hydrogen sulfide. If, on the other hand, everyone thinks they're going to die, and breathes deep in a panic, the rescue workers can bore their way into the still oxygenated chamber, and find that everyone died of hydrogen sulfide poisoning.
        • by sjames ( 1099 )

          If the concentration of H2S in the bottles is appropriate then breathing fast or deep will speed up the equilibrium between the blood level and the breathing gas, but won't cause an OD.

      • treating them for Crush Syndrome and for the poison that kept them alive by killing them slowly.
        I'm stealing that line and writing a love song...
    • by ErikZ ( 55491 ) *
      It would be great for in-system space travel.

      Reducing the need to eat and drink would greatly reduce the mass of the ship. Or greatly increase the amount of supplies you had when you arrive at your destination.
    • [...]our next step will be to study the use of hydrogen sulfide in larger mammals.'

      That's where the fun starts. Pull out the chimps! When we were kids we had to put little kittens in plastic bags and threw to to a brick wall. Now we get a lot of money for it. How beautiful science can be.
  • by apodyopsis ( 1048476 ) on Wednesday March 26, 2008 @05:06AM (#22867382)
    Thats great, now all we need is a heuristic computer with a suitable monitoring alogrithm to look after them whilst they are sleeping/hibernating. Still, good luck looking for volunteers for those trials.
  • Old News (Score:5, Informative)

    by Smordnys s'regrepsA ( 1160895 ) on Wednesday March 26, 2008 @05:15AM (#22867404) Journal
    Can we get an update? There have already been tests involving pigs (lifted straight from the wikipedia [wikipedia.org] entry)

    Induced hibernation

    In 2005 it was shown that mice can be put into a state of suspended animation-like hypothermia by applying a low dosage of hydrogen sulfide (80 ppm H2S) in the air. The breathing rate of the animals sank from 120 to 10 breaths per minute and their temperature fell from 37 C to just 2 C above ambient temperature (in effect, they had become cold-blooded). The mice survived this procedure for 6 hours and afterwards showed no negative health consequences.[6] In 2006 it was shown that the blood pressure of mice treated in this fashion with hydrogen sulfide did not significantly decrease.[7]

    Such a hibernation occurs naturally in many mammals and also in toads, but not in mice. (Mice can fall into a state called clinical torpor when food shortage occurs). If the H2S-induced hibernation can be made to work in humans, it could be useful in the emergency management of severely injured patients, and in the conservation of donated organs.

    As mentioned above, hydrogen sulfide binds to cytochrome oxidase and thereby prevents oxygen from binding, which leads to the dramatic slowdown of metabolism. Animals and humans naturally produce some hydrogen sulfide in their body; researchers have proposed that the gas is used to regulate metabolic activity and body temperature, which would explain the above findings.[8]

    However, a 2008 study failed to reproduce the effect in pigs, concluding that the effects seen in mice were not present in larger mammals. [9] [pccmjournal.com]
  • If you have a suspended mouse, just check the ball hasn't got fluff on it.
    For wireless mice, check the battery level and ensure its paired correctly with its base station.
  • by VincenzoRomano ( 881055 ) on Wednesday March 26, 2008 @05:24AM (#22867446) Homepage Journal
    You can also enable long term space travels with such a finding!
  • Linux (Score:5, Funny)

    by MortenMW ( 968289 ) on Wednesday March 26, 2008 @05:26AM (#22867462)
    They can suspend a mice, but making Ubuntu suspend on my laptop and work afterwards; that they can't do. It's a strange world
    • They can put a mouse on Alpha Centauri, but they can't [...]
    • They can suspend a mice, but making Ubuntu suspend on my laptop and work afterwards; that they can't do. It's a strange world

      Bah! I had a Dell desktop hooked up to a Microsoft ergonomic keyboard with all of those extra buttons once.

      I once inadvertently hit the "Sleep" button. The machine went into a hibernate state that I couldn't get it out of. I asked our IT guy, and he said he's never found a way out of that state. The only solution (we could find) was to fully power off and cold boot.

      I'm not convinc

      • Indeed.

        I had an ancient laptop many years ago whose hibernate mode could be interrupted only by pressing a key on the built-in keyboard, not the external keyboard. The internal keyboard had broken down long ago (the laptop was retired as a desktop), so the hibernation mode became a sleep of death.
  • by thrill12 ( 711899 ) on Wednesday March 26, 2008 @05:31AM (#22867486) Journal
    ...I am doing something good to people when I fart [wikipedia.org] in a room ?

    prrrrtttttttttttttttt......
    "Ok, who left the fart ?"
    "It was me ! I wanted to prolong your lives !"
    "That's a kind of frank boldness I haven't seen before...."
    • Re: (Score:2, Funny)

      Hey, you are right of course.
      I don't know about you, but whenever anyone farts nearby my metabolism slows right down and I practically stop breathing.
      (of course running for the door/window is another alternative)
    • Re: (Score:3, Insightful)

      by rubycodez ( 864176 )
      only if there is high sulfide content.

      mere loud and long exhibitionist expulsions won't cut it, they need to *stink*. silent but deadly wins over foghorn-like showboating.
  • If I put my "Tom And Gerry" DVD on pause, I too can create "suspended animation" of a mouse without freezing a mouse.
  • A tragic youth, wasted, attempting to put Mc Donalds restaurants into suspended animation..
  • by Pedrito ( 94783 )
    Wow, this is really new [slashdot.org] and interesting stuff. I can't quite put my finger on it, but reading it gives me the strangest sense of deja vu [slashdot.org].
  • I can see it now. An elevator in a high rise office building reaches the main floor. When the door opens, a car full of unconscious people is revealed. Subsequent investigation proves that the exhaust fan failed two floors below a stop on Floor 99, where the offices of the Beerf, Art & Ghasper Pickled Egg & Sausage Supply, Ltd. are located.

    I think the old saying was, "It's an ill wind that blows nobody good".

  • Just wondering... (Score:5, Insightful)

    by o'reor ( 581921 ) on Wednesday March 26, 2008 @07:36AM (#22868056) Journal
    ... some towns around the planet have quite a reputation for having a high sulphur rate in their atmosphere (Rotorua [wikipedia.org] in NZ is nicknamed "Sulphur City" because of that -- you can actually smell it when you're getting close to the town, and it takes a little while to get used to breathing that air !). Why don't they conduct a survey on the metabolism of the people naturally exposed to those gases ?
  • 2005.

    See Wikipedia "Hydrogen Sulfide".
  • Enough! (Score:4, Funny)

    by Fear the Clam ( 230933 ) on Wednesday March 26, 2008 @08:14AM (#22868334)
    Enough of this fake "science" funded by corporations like Taco Bell.
  • by HikingStick ( 878216 ) <z01riemerNO@SPAMhotmail.com> on Wednesday March 26, 2008 @08:29AM (#22868468)
    At the Lutheran church I attended as a child, the well water came up through a sulferous layer of rock. Every time the water ran, the place reeked of rotten eggs. Maybe it wasn't the sermons that put us to sleep all those years...
    • At the Lutheran church I attended as a child, the well water came up through a sulferous layer of rock. Every time the water ran, the place reeked of rotten eggs. Maybe it wasn't the sermons that put us to sleep all those years...
      On the bright side, maybe those hours spent there are hours of your life that you got back.
    • When your church reeks of brimstone, maybe it's time to look for a new church. Was there a pentagram in the basement too?
  • by dkleinsc ( 563838 ) on Wednesday March 26, 2008 @08:39AM (#22868578) Homepage
    This whole suspended animation thing would be wholly unnecessary if they had just supplied the cruise liner with the full complement of lemon-soaked paper napkins from the beginning.
  • Just curious how this keeps brain tissues alive? Without a constant supply of fresh oxygen the brain tissues begin to die in 5 minutes (give or take). If the hydrogen sulfide slows the heart rate that much, wouldn't those tissues suffocate, causing sever brain damage?
  • It's bad enough passing the oil refinery on the 101 north of Ventura, that has it's eternal 30 foot flame of burning Hydrogen sulfide. The stench is nauseating along one of the most visually beautiful stretches of highway on earth as is hugs along side the pacific.

    Now your telling me that we are going to have to smell this nasty stuff all the way to mars and beyond?
    Talk about ruining the trip of a lifetime.
    I'd rather take my chances with being frozen.

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