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Medicine Science

Spinal-Fluid Test Confirmed To Predict Alzheimer's 138

Posted by Soulskill
from the denny-crane dept.
omnibit writes "The New York Times reports that researchers have found a spinal-fluid test can be 100 percent accurate in identifying patients with significant memory loss who are on their way to developing Alzheimer's disease. The new study included more than 300 patients in their seventies, 114 with normal memories, 200 with memory problems, and 102 with Alzheimer's disease. Their spinal fluid was analyzed for amyloid beta, which forms plaques in the brain, and for tau, another protein that accumulates in dead and dying nerve cells in the brain. Nearly every person with Alzheimer's had the characteristic spinal fluid protein levels."
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Spinal-Fluid Test Confirmed To Predict Alzheimer's

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  • I hope that an easy text will be developed from this in the next few years. I couldn't imagine walking into a haze of Alzheimer's without knowing about it. This is one of those tests that I will ABSOLUTELY not be missing once I book it in.
    • Re: (Score:2, Insightful)

      by solevita (967690)
      And on the plus side, if you do have Alzheimer's you will at least be able to forget about the late life spinal tap.
    • Re:Thank goodness: (Score:4, Insightful)

      by Rei (128717) on Monday August 09, 2010 @07:52PM (#33198214) Homepage

      Yeah... too bad it's a spinal fluid test. Those are nasty. My spouse had one and the hole in the dura refused to close, which is apparently a fairly common side effect. Net result: unbearable, nonstop, over-10-on-a-1-to-10-scale headaches that can't be controlled with headache medicine. Caffeine on an IV drip works, but only temporarily. The headaches lasted for weeks until the doctors finally managed to close the hole with a blood clot. The clot doesn't actually fix the problem, but the dura managed to repair itself while the clot held. I've heard of people, however, who *never* healed from it. What a miserable experience.

      • Re:Thank goodness: (Score:5, Informative)

        by ColdWetDog (752185) on Monday August 09, 2010 @08:00PM (#33198304) Homepage
        That happens, but it is rare. But because of the potential numbers of people who would want the test, the difficulty of doing a lumbar puncture (spinal tap) on persons who have arthritis in the back (very common among us ancient folk), are of the supersized persuasion, or have other reasons to dissuade themselves, I don't think this is going to be the ultimate test.

        Instead it will serve as a proxy to allow simpler tests to be developed. TFA also notes that PET scans are fairly accurate. These are available at many larger medical centers but are also pretty pricey and technically complex.

        This is also not the first time that lumbar punctures for beta amyloid [elements4health.com] have been used to diagnose Alzheimer's. And finally, the abstract [ama-assn.org] of the original article for your viewing pleasure.
        • Re: (Score:3, Informative)

          by Rei (128717)

          The debilitating headache is not rare; it occurs in a third of all cases and normally lasts 24-48 hours. What's rare is when it lasts a year or more. Somewhere in-between is my spouse's case, which lasted a couple weeks and took medical remediation.

          • by epp_b (944299)
            Actually, if the procedure is performed properly and you actually lie flat in a bed for two hours like you're supposed to, the risk of headache is very low.
            • by Rei (128717)

              Link [mayoclinic.com]: "Spinal headaches occur in up to 30 percent of those who undergo a spinal tap (lumbar puncture) or spinal anesthesia."

              And almost nobody gets up during those two hours because the doctors typically make you lie flat. The dura just doesn't deal well with being punctured. Some people heal quickly. But a large minority don't. And some never heal.

        • ...are of the supersized persuasion...

          You mean, like a huge cock?

          Sucks for those guys.

        • by tkjtkj (577219)
          Your comment "But because of the potential numbers of people who would want the test, the difficulty of doing a lumbar puncture (spinal tap) on persons who have arthritis in the back (very common among us ancient folk), are of the supersized persuasion, or have other reasons to dissuade themselves, I don't think this is going to be the ultimate test." is misleading. As a retired anesthesiologist with well over 20 years medical experience i can state that i have never experienced any patient whom i could n
          • ... but in the hands of a professional your concern is misguided.

            My point being that a technically difficult test, one that requires a significant amount of specialty training, isn't ideal for something that may end up being a screening test (where you are testing a large number of people, most of which won't have the problem). That also is an issue with PET scans since they're technically demanding and complex.

            The utility of having a fairly specific test for Alzheimer's, on that doesn't require brain b

      • Re:Thank goodness: (Score:4, Interesting)

        by Have Brain Will Rent (1031664) on Monday August 09, 2010 @08:21PM (#33198456)
        Yup my Dad had that done and he said it was the most painful thing he'd ever had happen... and this was a guy who grew up on a farm (a great source of pain), served years in combat during WWII and so on and so, on without ever raising a complaint.

        The next time he had to go in was because of a disc problem and they essentially injected his spine with meat tenderizer to dissolve the ruptured disk away. He said compared to the spinal tap that didn't hurt at all (except for the nurse yanking his boxers off without first checking for protrusions - yikes!).
        • Re: (Score:3, Interesting)

          by CrashandDie (1114135)

          I've never had meat tenderiser shot up my back, but I've had two lumbar punctures. The first one wasn't too bad, the second one was almighty awful.

          The only thing I underwent that hurt more was after a fight (I was doing street photography and was attacked by a bunch of youth), I had a corneal abrasion on my left eye. My understanding of it is that there was a small hole, gap, or something, on the outer layer of my eye, against which my eyelid rests. I had this small gap dead centre in front of my iris (or w

      • Yeah... too bad it's a spinal fluid test. Those are nasty.

        I'm with you -- though I suppose it would only applied as a 'final confirmation' sort of test to rule out much rarer neurological conditions, after all the other, less-invasive tests had been exhausted.

        Truth be told, the result described in the paper isn't particularly exciting; it just looks at a larger population of patients than has been used in the past, and teases out some correlations that were already expected. It may also explain some minor contradictions between previous studies that (could hav

    • Re: (Score:2, Troll)

      by c0lo (1497653)

      I hope that an easy text will be developed from this in the next few years. I couldn't imagine walking into a haze of Alzheimer's without knowing about it. This is one of those tests that I will ABSOLUTELY not be missing once I book it in.

      :) Suggestion: make sure you make a note - actually, many of them - and post them all over in your home: this is to avoid the risk of forgetting about the test by the time it gets approved :)

      • by c0lo (1497653)

        Apologies, I thought the smiley-s would clearly indicate the post as meant to be on the funny side (and by no means offensive, flame-ing, much less trolling).

        On the serious side, if the original poster thinks her/himself at risk, I wouldn't recommend the original poster to skip any Alzheimer's test just because of this piece of news: given the time required for FDA's approval [wikipedia.org] it may be too late (granted, since it is a test only, the time to approval may be shorter than for a drug, but anyway...)

    • by Kepesk (1093871)
      What was this test for? I can't remember... And how did I get up in this tree?
    • Actually, I don't think this test is all that useful. According to the article, the test was validated for people with significant memory loss. Alzheimer's can really be diagnosed clinically in that group, so the test won't add all that much, and if it is from spinal fluid then it involves a painful and invasive lumbar puncture (spinal tap). I would say that this test is of academic interest, a step in the right direction towards finding a test that can be used early on. There is more interesting researc
    • by HiThere (15173)

      Why?

      If there's a treatment, then it might be useful to know early if you're going to get it. If there's no treatment, it only means that your health insurance is going to start looking for excuses to cancel your policy.

  • I know that amyloid beta in the Cerebrospinal fluid is a secondary symptom of plaques on neurons, but I wonder of filtering or replacing the CSF would help the situation at all?

    • I'd guess it wouldn't be worth the expense since, as you noted this is secondary. It's not even a secondary -symptom-. It's not going to do anything besides cause massive headaches. Literal headaches, that is. It would be a bit like trying to fight a fire by clearing the smoke out of a burning building.

      • massive headaches

        Yeah I know. My nephew has fungal meningitis, which is weird, nobody knows where it came from. He is otherwise very healthy. His condition was diagnosed when the infection pushed up the pressure of his CSF and caused exactly those symptoms.

  • by Alphanos (596595) on Monday August 09, 2010 @07:54PM (#33198230)

    So, just to clarify, this test "can be 100% accurate", while at the same time "Nearly every person with Alzheimer's had the characteristic spinal fluid protein levels."

    That's a pretty neat trick.

    • 60% of the time, it works every time.

    • by GNUALMAFUERTE (697061) <almafuerte.gmail@com> on Monday August 09, 2010 @08:03PM (#33198332)

      Yeah, not only that, but also it says that many people without Alzheimer's turned out positive too ... so they assumed those are going to develop Alzheimer's.

      It produces false negatives, and it might be producing false-positives, but we won't know until 10 or 20 years later. But it still is 100% accurate. Nice math there. This trend of early publishing non peer reviewed material while making extraordinary claims, only to never hear from it again is starting to get really old.

      • by BitZtream (692029)

        Peer reviewed ... heh, a simple random 'read it myself before I hit submit' should fix most of this kind of crap it seems to me.

      • by timeOday (582209) on Monday August 09, 2010 @09:44PM (#33198964)
        Read it again, because there is nothing in the article that contradicts the claim that "researchers have found a spinal-fluid test can be 100 percent accurate in identifying patients with significant memory loss who are on their way to developing Alzheimer's disease.":

        "Nearly every person with Alzheimer's had the characteristic spinal fluid protein levels. Nearly three quarters of people with mild cognitive impairment, a memory impediment that can precede Alzheimer's, had Alzheimer's-like spinal fluid proteins. And every one of those patients with the proteins developed Alzheimer's within five years. And about a third of people with normal memories had spinal fluid indicating Alzheimer's. Researchers suspect that those people will develop memory problems. "

        However, the test can only be 100% accurate if the spinal fluid proteins that presage Alzheimer's decrease after full onset.

        The fact that not everybody who tested positive developed Alzheimer's during the study is no counter-indicator at all, especially if they kept testing new subjects throughout the trial (i.e. some were only tested recently).

        Of course, the usual caveats apply - you can't predict with 100% accuracy who will develop Alzheimer's years from now because some will die first of other causes. And in biology (and medicine), even if your test is correct on the first 10 patients, and the first 100, and 1000, you just know some smart-alec is going to buck the trend eventually :) Biology is just too messy to follow any simple rules all the time. But that doesn't necessarily have a whole lot of relevance to clinical applications.

        • NEARLY. NEARLY. They said NEARLY every person with Alzheimer's tested positive. If NEARLY every person develops the characteristics you are testing for, NEARLY ALL ALL. NEARLY 100%. That means they are getting FALSE NEGATIVES.

          On the other hand, out of the people tested, many were POSITIVE, but we don't yet know if they are going to have Alzheimer's or not. So, we MIGHT HAVE FALSE POSITIVES.

          That is exactly what my post said.

          Don't get me wrong, a technique to easily prove for a hard to detect and identify d

          • by timeOday (582209)

            NEARLY. NEARLY. They said NEARLY every person with Alzheimer's tested positive. If NEARLY every person develops the characteristics you are testing for, NEARLY ALL ALL. NEARLY 100%. That means they are getting FALSE NEGATIVES.

            That's not the point - the claim was that "researchers have found a spinal-fluid test can be 100 percent accurate in identifying patients with significant memory loss who are on their way to developing Alzheimer's disease." You are inferring that people who already have Alzheimer'

          • by priegog (1291820)

            Don't get me wrong, a technique to easily prove for a hard to detect and identify disease, that has a low rate of false positives/negatives is still AWESOME.

            Too bad in reality what you're describing is VERY VERY rare (and much more so if you also wish it to be cheap). That's why statisticians have created measurements that help when taking clinical decisions. For instance, for a screening test (which seems like this is what it's planed to be) it's perfectly acceptable to have a high sensibility even if it has a low specificity. This way you'll "catch" almost all of the sick people for further study (with more specific, and most likely more expensive/time consum

          • by ebuck (585470)
            You have to be very careful because you don't know who wrote the NEARLY. It could have been a researcher or a journalist. Hold your judgement until you get your grubby hands on the actual research paper.
      • by sjames (1099)

        I wonder if the statistician tested positive?

      • by elrous0 (869638) *
        Too many "researchers" are way more interested in getting more grant money through PR and exaggeration than they are in real science.
    • by jethr0211 (996156)

      Probably meant they predict near zero rate of false positives.
      Ahh, statistics; in the hands of amateurs, any conclusion is possible.

    • by rickyb (898092)
      Exactly. Especially in medicine, no diagnostic test can ever be considered 100% accurate unless it could be tested on every single person who ever had the disease in question and who ever will have the disease. Try getting funding for that! Any article (or summary of an article) discussing the statistics of a diagnostic test should also include mention of the specificity and sensitivity of the test. Biostats 101, guys (and gals).
    • This is simple to clarify. The tests to detect these proteins are not 100% perfect but they get more sensitive every year. So just because they are not detectable in certain patients does not mean they are not there. So, this paper just came out recently, that means it was probably submitted for review 3 months (or more) and the actual experiments may have taken place at least a year ago. So in that time, the tests for these proteins have improved yet all the samples that were collected a year or more ago h
    • Re: (Score:1, Troll)

      by dissy (172727)

      Yes, because news reporters don't know how to be accurate or consistent, lets just ignore and discredit the real scientists work :/

    • by priegog (1291820)

      That's why when doing actual hard medicine (and taking important decisions regarding implementing certain test and whatnot) these claims do not bode. "100% accuracy" (or any percentage, really) means squat to a statistics-trained professional. There are precise measurements of the effectiveness and potency of a particular test, these mainly been sensibility and specificity. So a particular test may be very sensible yet not very specific (like the mammography, for detecting breast cancer), which means it can

  • by Garrett Fox (970174) on Monday August 09, 2010 @08:00PM (#33198300) Homepage
    I'd heard years ago that there was dispute between researchers who thought the disease was caused by "beta amyloid plaques" versus by this "tau" protein. Does the test for both show that there's still no consensus on the cause, or has one been established as the cause and the other an effect?
    • Re: (Score:3, Funny)

      by Mishotaki (957104)
      Tau? i'd bet it's the Orks, not the Tau that's the problem!
    • Re: (Score:3, Interesting)

      by interkin3tic (1469267)

      Does the test for both show that there's still no consensus on the cause, or has one been established as the cause and the other an effect?

      I think the fact that both are used merely shows that there's consensus that both are strong markers of the disease. Actually proving cause and effect is going to require better animal models, better culture systems to replicate the disease in a dish, or people willing to sacrifice themselves. I heard a seminar about 3 years ago by a "tauist," who was arguing that if you artificially expressed tau in mouse brains, their neurons started acting like early stages of alzheimers, but the mice never developed p

      • Hmm, that's true. If (say) Tau is the root cause but it works by causing the BAP plaques, then we only really need to disrupt either of them and it doesn't matter which. It looks like clinical trials [cogknow.eu] are planned for a "vaccine" that attacks the BAP, so hopefully we'll get some useful results from that even if we don't fully understand why it works.
  • by Eccles (932) on Monday August 09, 2010 @08:00PM (#33198306) Journal

    Not only does this give an actual test for Alzheimers, it also means that there's a definitive symptom for it. Wipe out the cause of that symptom and maybe you can stop or reverse the progression of this horrible affliction.

    My father is already at the moderate dementia stage of this illness, and it's devastating. Not so much for him as it is for my mother.

    • Let's first see exactly what the test is. If they test for amyloid beta peptides, the test may give false positives (a lot of people with amyloid beta plaques have not had any cognitive decline (note that prior to this test, the plaques could be only detected posthumously)). And if this "new" test is like the one I have read about previously, then it does only look for Abeta peptides. And nowadays most of the Alzheimer's durg research is moving in the direction of the Abeta plaque removal or prevention of t

    • That said, I feel very much with you, regarding your father's dementia. In this phase (before apathy sets in), AD is a frightening experience for the patient, too, especially if he/she was/is an intellectual worker, such as a researcher or such. Forgetting words that you used commonly, is scary. Forgetting the names of your colleagues is scary. Forgetting the names of your friends is scary. It's not easy. Then, at the more severe stage, the patient becomes apathetic and then, I guess, it's easier for him/he

      • by Eccles (932)

        Thank you for your kind thoughts, but I really do think it's too late for him. For my wife's sake, I hope for one for me. For my mother's sake, I hate to think this way, but... well, I won't say it, just think it.

        As a general rule, my father doesn't seem scared, just confused, although he's had a strange paranoia about money. This despite a generous retirement pension/savings/etc.

        • I have no idea of the stage in which your father is in, and certainly I have no right to tell you anything. But I think it's always better if you do't give up hope on him, yet. Because if you fight for him as hard as you possibly can, you will know that you'll do it for yourself, too, if and when the time comes.

          By the way, have you tried giving him curcumin (curcuma extract)? There appear to be more and more articles in journals (such as Journal of Neurochemistry) that describe almost immediate benefits to

    • by priegog (1291820)

      Unfortunately, it's been known for a number of years now that the histological characteristics of alzheimers were the accumulation of beta-amyloid and the presence of tau protein, so this test is only that, a test, not any significant discovery on the disease itself...

  • From TFA:

    One drawback, though, is that spinal fluid is obtained with a spinal tap, and that procedure makes most doctors and many patients nervous. The procedure involves putting a needle in the spinal space and withdrawing a small amount of fluid.

    I know that more education is needed in this area. Any thing involving the back is inherently risky. The wikipedia article indicates [wikipedia.org]. that well the risk is low it is a major procedure and not many people will be comfortable in having one for just a test.

  • Amyloid-beta plaques are not a necessary condition for Alzheimer's. I don't know, of course, the details of this latest cerebrospinal fluid test, but the previously published one was only looking for traces of Abeta peptides. If the claim of 100% accuracy is actually true (we have to see the article), then it perhaps also takes into consideration tau protein traces. I am really just speculating here, but tau protein tangles seem to be clearer indicators of Alzheimer's disease.

    Many people have been found to

    • Re: (Score:3, Informative)

      Amyloid beta was there and it was targetable by the methodology available to drugs companies. Now, they've discovered it doesn't work, and there's a few years of lag time between findings synchronising. I don't think there are any more gamma-sec or beta-sec programs in drug discovery. Let's just hope there's another target around.

      • Virtually all current Phase III evaluations center on Abeta. Sadly.

        • I'm a chemist and I've worked on a gamma-sec modulator, so I see it from the bottom up. Drugs might be in human trials but I don't think there's any new discovery programs.

          • I'm extremely happy to meet someone "on the inside". Can you please tell me, in your personal but informed (much more informed than mine, anyhow) opinion, what is the most likely candidate for a decisive cure for AD, currently being researched?

            • I only made the molecules and I saw a tiny corner of the industry as it was in 2008. I have general common sense in the field but I really can't say without it being my opinion.

              The current thrust has always been about targeting a specific symptom (the plaques) but my feeling is that even if we get a working aB42 inhibitor, it won't stop senility. I read a few years ago about a preventative treatment that halted cognitive decay, based on a substituted ibuprofen, but I can't recall of any of the details.

  • by RabbitWho (1805112) on Monday August 09, 2010 @08:17PM (#33198422) Homepage Journal
    There's no treatment for it and nothing they can do. I'd rather not know for as long as possible, you start going crazy as you watch yourself deteriorating every day. If I forget and put door keys in the microwave I think "oh I'm such an idiot." and laugh. I don't feel the terror that someone with Alzheimers feels, thinking every mistake is a sign.
    • Re: (Score:3, Insightful)

      by olsmeister (1488789)
      While I tend to agree with your position, there are many who would want to know, particularly if there is a family history of this disease. It might affect your planning for the future, and even the way you live your life today.
    • by phantomfive (622387) on Monday August 09, 2010 @09:43PM (#33198958) Journal
      Watching my grandpa suffer through Alzheimer's, this is a real issue. At first he took it with a sense of humor, when I called he'd say, "hey, I almost forgot about you! Call more often!" But soon I could see it was really getting to him, and he was starting to withdraw into that stupor that people get into at convalescent homes.

      So I forced him to be active; when he tries to tell me something, and can't think of the word, I just wait for him to spit it out, or tell him to explain it a different way. Get him active, help him see that life can be good even though he doesn't remember quite as well. I treat him like a human and make him connect to me like a human. No withdrawing into that shell just because you can't remember well. I took him to see giant trees and waves and stuff. Giant trees and waves always make you feel alive.

      So now he is happier, got over his anger streak, and he doesn't worry if he can't remember everything (it doesn't matter if you can find a way to work around it).
      • I guess there are a lot of things that can make it easier to deal with, but there is nothing that can slow it down or stop it.

        It's great to read your experience with your grandfather, you must be a great comfort to him.
        • Yeah, I know that's true, but I'm going to make sure his memory he does lose is from alzheimer's, and not from some old-age malaise!
    • To an individual, maybe not, but for drug trials, yes. Knowing definitively that your test subjects had the disease or did not would be better than judging by symptoms. I'd also wager that there are probably a few other non alzheimers problems that show similar symptoms early on, it would be valuable to know if it was AZ or not AZ and instead might be a brain tumor, for example.

    • and power is um... pancakes

    • Re: (Score:3, Insightful)

      by dr_dank (472072)

      There's no treatment for it and nothing they can do. I'd rather not know for as long as possible, you start going crazy as you watch yourself deteriorating every day.

      And to think we used to cluck our tongues at the people who ate badly, smoked, drank, etc who died of a coronary at 60-70. Now you can live to 90 and be a vegetable. Hooray.

      Until the mind can be prolonged the same way medicine has prolonged the body, it's all for nothing.

      • Of course it's not "all for nothing". Not everyone gets Alzheimers, strokes and brain tumours.
        Ordinary dementia can be fought tooth and nail by reading/listening to the radio/watching television/having friends and family around you.

        My grandfather lived to be 87 and was sharp as a tack right up until the day he died.
    • Re: (Score:3, Insightful)

      Yes, let's leave you not knowing and continuing to drive, or forget what checks you've signed, or whether your spouse is allergic to peanuts when you make her a sandwich, and leave you without a chance organize your finances, any insurance, and a living will for a years long debilitating illness.

      Then you can get promoted to middle management, where you can cut costs by discarding that "unnecessary testing".

    • Re: (Score:3, Interesting)

      Currently the correct treatment is suicide. Early knowledge is very important, because later when the suffering really begins for you and your family, you will be helpless. You might argue that one could exit too soon, but a good death can't really be too early.
  • There is a bunch of research [google.com] out there pointing out that proper exercise can reduce your risk for Alzheimer's and other forms of dementia by something like 70-75%. So its great there is a test and all, but you can still effect the outcome SIGNIFICANTLY with your lifestyle choices. There is also a link to fruits / vegetable intake as well.
  • This is an expensive test with a fairly high side effect profile. On top of which, a positive result leaves the doctor and patient with no change in treatment options. Since Alzheimer's is an uncureable disease, early diagnosis doesn't accomplish anything. Neuro-Psychological tests (DRS-2) have very high accuracy in diagnosing the disease in late-early and moderate staged disease. The real question is... we have a positive (or negative) result, so how does this change our proposed treatment. The answer

  • Good job guys

  • I'm looking forward to committing the pillage and plundering knowing I won't have to remember the consequences afterward...
  • It may be a useful test but watching This Is Spinal Tap is a painful experience and should be avoided if at all possible.

  • by pgmrdlm (1642279) on Monday August 09, 2010 @10:18PM (#33199148) Journal
    I don't know if this is good or not. Please let me explain.

    If you have ever had the misfortune of having a relative with Alzheimer disease, you know they are nothing like the person you loved and cherished. Everything from forgetfulness, to wanderings where you search the streets for them, to the extreme mood swings where they get violent. Its a terrible experience for both you and the people that have this disease.

    If you are diagnosed with this disease in advance, and there are no cures? How do you tell your family and friends? What are you going to think about the pain you know that you may be putting them in?

    Knowing how my mother became with this disease, if I find out that I have it and there are no cures. I don't want to put my friends and family through the same experience. I would rather drive my car into a wall at 120 miles an hour.

    Just my perception, sorry.

  • So great - you'll know if you're doomed. That sounds like fun.

    I'd rather see more data on a cure before I'm supposed to invest myself psychologically in the diagnostics. I've heard things being developed, and ways to help prevent, but living a life with a lit fuse running into your skull doesn't sound like a miracle of medicine - it sounds like a death-clock at the least, and a suicide watch at the most.

    Count me out.
  • I have found a non-intrusive test that is 100% accurate in identifying patients with significant memory loss. http://www.toysrus.com/product/index.jsp?productId=2264802&CAWELAID=107512504 [toysrus.com]
  • Is there any sense in doing a rather nasty test for a disease we can't cure yet anyway? It's not like you can fix it if you find out early.
  • by RichiH (749257) on Tuesday August 10, 2010 @07:15AM (#33202140) Homepage

    How I love Slashdot summaries.

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