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New Nanoparticle Could Provide Simple Early Diagnosis Of Many Diseases

ScuttleMonkey posted more than 7 years ago | from the making-you-glow dept.

Biotech 62

Researchers have created a new nanoparticle that could someday act as a virtually all-purpose diagnostic tool to detect many inflammatory diseases in their earliest stages, including heart disease, Alzheimer's, and arthritis. The specially-designed nanoparticles seek out hydrogen peroxide (thought to be overproduced in trace amounts in the early stages of most diseases that involve some sort of chronic inflammation in the body), and emit light when they encounter it.

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Finally a foolproof test (3, Funny)

Anonymous Coward | more than 7 years ago | (#20294863)

We can tell the fake blonds from the true blonds without checking the carpet!

Re:Finally a foolproof test (4, Funny)

wolfgang_spangler (40539) | more than 7 years ago | (#20295069)

I'd rather just check the carpet and I'll let you know.

Re:Finally a foolproof test (1)

0100010001010011 (652467) | more than 7 years ago | (#20295643)

I much prefer linoleum.

Re:Finally a foolproof test (1)

Harmonious Botch (921977) | more than 7 years ago | (#20297259)

I use bedsheets

AIDS (-1, Offtopic)

Anonymous Coward | more than 7 years ago | (#20294869)

AIDS

so (5, Funny)

JeanBaptiste (537955) | more than 7 years ago | (#20294871)

if I see anyone glowing I'll avoid them. I've been doing that anyways....

Ever seen a girl with a real post-orgasmic glow (1)

crovira (10242) | more than 7 years ago | (#20298755)

enveloped by a soft sheen of post-prandial perspiration, just collapsing back on the pillows and sighing?

Oh... This is /.

Sorry... :-)

Re:Ever seen a girl with a real post-orgasmic glow (2, Informative)

fractoid (1076465) | more than 7 years ago | (#20299755)

Re:Ever seen a girl with a real post-orgasmic glow (1)

gatsby0121 (977892) | more than 7 years ago | (#20303559)

Depends on what he ate.

Re:Ever seen a girl with a real post-orgasmic glow (1)

fractoid (1076465) | more than 7 years ago | (#20304179)

Sir, you make an excellent point!

My.... (3, Funny)

Anonymous Coward | more than 7 years ago | (#20294885)

You have an unhealthy glow about you!

Dear, you look radiant. (3, Funny)

pragma_x (644215) | more than 7 years ago | (#20296435)

Get your coat. It's time to go to the hospital.

Cancer Test (4, Funny)

MyLongNickName (822545) | more than 7 years ago | (#20294889)

1. Inject billions of nanoparticles into lungs
2. Proclaim person has pre-cancer
3. Be right 100% of the time.
4. Profit!

Re:Cancer Test (0)

Anonymous Coward | more than 7 years ago | (#20304207)

I believe you are missing a simple, but crucial step:

    3. Be right 100% of the time
  (4) ...
    5. Profit!!!

This is why I hate Open Source (-1, Offtopic)

Anonymous Coward | more than 7 years ago | (#20294893)

All I want to do in read about Ubuntu Studio, see what software is included, so I can decide if it will replace my aging Mac with Adobe CS. I can't afford a direct replacement at the moment.

And I Google "Ubuntu Studio" to find the official site [ubuntustudio.org] and I'm greeted with some less-than-clever gibberish that means nothing to anyone who isn't already an Open Source geek. A tinyurl link, some dumb mumbling about Google cache.

You people can't even run a web site.

I have some early detection tests too! (4, Funny)

UbuntuDupe (970646) | more than 7 years ago | (#20294895)

Here are mine:

1) Heart disease: You can't fit your lardass into an airplane seat.

2) Alzheimer's: Grandma asks the name of the TV show three times within ten minutes.

3) Arthritis: You're better at DDR than Guitar Hero. :-/

Re:I have some early detection tests too! (1)

JazzyMusicMan (1012801) | more than 7 years ago | (#20295755)

I have pretty bad arthritis and I'm pretty good at Guitar Hero, DDR would be nearly impossible for me to play.

This is no good. (2, Funny)

morgan_greywolf (835522) | more than 7 years ago | (#20294907)

The specially-designed nanoparticles seek out hydrogen peroxide (thought to be overproduced in trace amounts in the early stages of most diseases that involve some sort of chronic inflammation in the body), and emit light when they encounter it.
No good. I just can't see how this going to work at all for Paris Hilton.

Re:This is no good. (1)

Muad'Dave (255648) | more than 7 years ago | (#20295155)

Her peroxide-blonde head will look like the friggin' Luxor in Vegas.

Combine 3 memes (1)

trolltalk.com (1108067) | more than 7 years ago | (#20294923)

"The specially-designed nanoparticles seek out hydrogen peroxide (thought to be overproduced in trace amounts in the early stages of most diseases that involve some sort of chronic inflammation in the body), and emit light when they encounter it"

  1. Invent beowulf cluster of nanoparticles that glows in presence of disease
  2. "...oh, shiney ..."
  3. PROFIT!

Re:Combine 3 memes (-1, Troll)

Anonymous Coward | more than 7 years ago | (#20295217)

LOLOLOL wait..that wasn't funny at all..

Great News for the Open Source Community!! (-1, Offtopic)

Anonymous Coward | more than 7 years ago | (#20294997)

"Why me?" thought Bob. "Why am I the one always getting sent to do 'ping' duty?" Bob was a small packet of data being sent through the phone lines to check to see if another computer was responding properly. 'Ping' duty was especially boring as it involved running to another system, ringing its doorbell and when the door was answered, running away again to report back to your home system. Bob was upset that he couldn't be doing something interesting such as sending data to an IRC channel or retrieving JPEGs from a porn site. Dan, the lucky packet, was probably right now off surfing through the World Wide Web for the User. Bob hated Dan. He got all the girls. Bob wondered: What was the user looking for today, on the WWW. Could it be news? Maybe he was posting on a messageboard for some obscure 10 year old game! Or perhaps he was talking on AIM to some of his friends! Or maybe he was racking up frags in Doom 3 or Half-Life II with people all over the world! Bob liked working with online games! There was always so much action! But every time he was assigned to game duty he ended up just 'pinging' the server so the program could check whether the user was still properly connected. Which brought him back to square one. As Bob ran through the various phone lines and such he began to see the system he was supposed to reach and 'ping.' He got there a lot faster than normal, seeing as how the User had got a 3 megabit/second DSL connection meaning that him and all the other packets were hooked up with little miniature jetpacks. It sure beat when the User only paid for 56 kilobits/second which meant that the packets just had crappy worn out running shoes which they purchased from some hobo packet who had been sent off to do something for the User and when he returned his system was gone, leaving him in the cybergutter of the cyberhighway. Most lost packets die when their time-to-live runs out, but not this one's. He had found an unprotected network which reset his TTL for free, and sent him back off, and as long as he visited it every few milliseconds, he would never die. Anyway, Bob reached his destination. The system was big and creepy looking and very dark. Bob nervously walked onto the cyberlawn and towards the cybersteps. He went up to the cyberdoor and rang the cyberdoorbell. No one answered at first. Bob got nervous and wanted to leave but he knew he couldn't until someone answered or it timed out, and he could run back to his system saying there was no response. Bob was a frail, skinny looking packet, I should mention. Suddenly the cyberdoor opened. Bob ran as fast as he could, back to his system. First of all those were his orders and second of all he didn't want to stay there anymore. Unfortunately someone grabbed him, before he could start moving. It was a giant window! Bob struggled but couldn't get away. He was dragged into the system. He passed out, an unusual occurrence among packets. Bob woke up. The system was extremely creepy. It was painted an annoying aquamarine color, and the floor was gray with a little start menu button. Bob recognized it as a Windows 95. "I wonder why this system is so old?" thought Bob. Despite its name there were no windows from which Bob could escape. Just then the giant window waddled into the room! It grabbed Bob and said "Now we're going to have some fun!" Bob couldn't take it anymore. The stupid window was torturing him! First he had demonstrated how horribly the operating system handled memory. Bob had started to twitch. Then it had demonstrated some shutdown issues the operating system had. Bob felt cybersweat trickle down his spine. But now, now Bob wasn't going to be able to handle it. He knew exactly what was next. And he knew he didn't have the stomach. The window was laughing maniacally. "AND NOW! HAHA! I WILL DEMONSTRATE ONE OF THE MOST TERRIBLE, DISGUSTING, THINGS ANY PACKET CAN WITNESS!" yelled the window. Bob felt sick. This was it. The window proceeded to attempt to access "c:\con\con." Bob felt bile rise in his throat. Then everything went blue. I will spare the details but it was not pretty. In the background echoing around him from everywhere was the window laughing, driving him insane. It had been a few hundred seconds since it had happened and Bob was barely getting over it. He couldn't believe he had been forced to witness the Blue Screen of Death. He had heard people back in his system talk about it in hushed voices but no one ever knew if it was true. It scared people to think that something could be as terrible as that. Bob was going to have to escape. Of course none of the options the BSOD gave the User worked. They were there to mock him, and the only way out was to restart your system and hope that you could boot up properly. Bob tried to get out. If the computer was restarted while he was inside, he would be lost forever! But the dark blue wall of pain was blocking his exit. Suddenly he had an idea, and he rushed out of port 80, the HTTP port. It wasn't closed properly because the stupid window forgot to close it, since it wanted to access web pages! Now he was on the World Wide Web. But he had to get back to his system fast for he didn't have a purpose and without a purpose his TTL would kick in. He visited http://www.network-tools.com/ [network-tools.com] and entered his System's IP address. He ran a trace route on it, and found his way back to his system. Trace routes are like packet's MapQuests. He was running very fast when suddenly his jetpack went out. "Crud!" he thought. "Verizon must once again be having server issues." Bob rolled his eyes. He was sick of how every major ISP was extremely lazy and unpredictable. He only had 200 milliseconds to get back to his system. But since he no longer even had his hobo-sneaks he was running at a sad 33.6 kilobits/second. He would never make it on time! That's when suddenly a huge penguin flew his way and picked him up. The penguin flew Bob home faster than the time it takes for a Windows system to crash. The penguin could fly because he was free. If you are free you can do whatever you want. Bob thanked the penguin, and told everyone his story, back at his system. Nobody cared.

those clever scientists.... (4, Funny)

tbischel (862773) | more than 7 years ago | (#20295105)

"Researchers have created a new nanoparticle that could someday act as a virtually all-purpose diagnostic tool to detect many inflammatory diseases..."
We can do anything now that science has invented magic

Sounds like nonsense (0)

uglyduckling (103926) | more than 7 years ago | (#20295115)

Most cancers, Alzheimer's and heart disease have nothing to do with inflammation, chronic or otherwise. Arthritis does, although I have never heart of hydrogen peroxide in relationship with it.

Re:Sounds like nonsense (2, Informative)

Anonymous Coward | more than 7 years ago | (#20295233)

Heart disease and heart attacks certainly DO have a lot to do with inflammation. see the anti-inflammatory properties of lipitor, and see also the use of high-dose statins in the setting of acute MI. also, educate yourself on the pathophysiology of atherosclerosis and the role of macrophages.

Re:Sounds like nonsense (5, Informative)

kebes (861706) | more than 7 years ago | (#20295397)

In the actual paper [nature.com] , they mention:

The overproduction of hydrogen peroxide is implicated in the development of numerous diseases 1-4 and there is currently great interest in developing contrast agents that can image hydrogen peroxide in vivo.
and:

The overproduction of hydrogen peroxide is implicated in the development of numerous inflammatory diseases, such as atherosclerosis, chronic obstructive pulmonary disease and liver hepatitis 23-27.
The implicated references, if you care, are:

1. Lim, S. D. et al. Increased Nox1 and hydrogen peroxide in prostate cancer. Prostate 62, 200-207 (2005).
2. Chang, M. C. Y., Pralle, A., Isacoff, E. Y. & Chang, C. J. A selective, cell-permeable optical probe for hydrogen peroxide in living cells. J. Am. Chem. Soc. 126, 15392-15393 (2004).
3. Miller, E.W., Albers, A. E., Pralle, A., Isacoff, E. Y. & Chang, C. J. Boronate-based fluorescent probes for imaging cellular hydrogen peroxide. J. Am. Chem. Soc. 127, 16652-16659 (2005).
4. Albers, A. E., Okreglak, V. S. & Chang, C. J. A FRET-based approach to ratiometric fluorescence detection of hydrogen peroxide. J. Am. Chem. Soc. 128, 9640-9641 (2006).
23. Polytarchou, C., Hatziapostolou, M. & Papadimitriou, E. Hydrogen peroxide stimulates proliferation and migration of human prostate cancer cells through activation of activator protein-1 and up-regulation of the heparin affin regulatory peptide gene. J. Biol. Chem. 280, 40428-40435 (2005).
24. Laurent, A. et al. Controlling tumor growth by modulating endogenous production of reactive oxygen species. Cancer Res. 65, 948-956 (2005).
25. Stone, J. R. & Collins, T. The role of hydrogen peroxide in endothelial proliferative responses. Endothelium-New York 9, 231-238 (2002).
26. Mohler, D. L. & Shell, T. A. The hydrogen peroxide induced enhancement of DNA cleavage in the ambient light photolysis of CpFe(CO)(2)Ph: A potential strategy for targeting cancer cells. Bioorg. Med. Chem. Lett. 15, 4585-4588 (2005).
27. Hirpara, J. L., Clement, M. V. & Pervaiz, S. Intracellular acidification triggered by mitochondrial-derived hydrogen peroxide is an effector mechanism for drug-induced apoptosis in tumor cells. J. Biol. Chem. 276, 514-521 (2001).
I'm not an expert in these matters, but looking over the paper, it seems that there is considerable interest in this diagnostic technique for a variety of conditions. (The fact that it was published in a high-profile journal like Nature Materials is already a good indication.)

Sounds like hope (0)

Anonymous Coward | more than 7 years ago | (#20296341)

This would have come in handy detecting many autoimmune diseases such as the one I have, Reiter's Syndrome. It was most likely triggered after my first sexual encounter in college. After a trip at the invitation of a friend to Mardi Gras I discovered that my date had left me with a nasty gift. It was first diagnosed as ghonnorhea, then clamidia, then ??? The uroligist could not get my white cell count in my prostate to return to lower normal even after massive doses of about every antibiotic and anti-fungal. This has lasted as prostititis for the last 20 years. Just recently (2005) I began having severe tendonitis in my hands and arms. Still do difinitive diagnosis. After another two years severe joint pain and tendonitis has rendered me unable to work due to the intense pain.

I have seen advances such as genetic therapy and now this come around in just that last few months. This could have saved myself and others with rare disorders the frustration of many year of complaining about unusual symptoms by backing us up with a means of measuring the progress of these disorders in an objective way. Doctors are trained to "when they see hoofprints to assume horses rather than zebras." These type tools and advancements in readily available diagnostics assistance can potentially help or cure millions.

Live your life as you would have the world be.

Re:Sounds like nonsense (0)

Anonymous Coward | more than 7 years ago | (#20295499)

The fact that the parent used the word "heart" when he meant to write "heard" leads me to believe that he is not a medical professional.

Re:Sounds like nonsense (0)

Anonymous Coward | more than 7 years ago | (#20295619)

He may not be a medical professional, but he could be a professional drinker.

Re:Sounds like nonsense (0)

Anonymous Coward | more than 7 years ago | (#20295821)

sadly, it seems he is in fact an MD, albeit one that is not up-to-date with the research. i've found this typical with these "something else, decided to go to med school" types.

Re:Sounds like nonsense (3, Informative)

philip_bailey (50353) | more than 7 years ago | (#20296677)

Most cancers, Alzheimer's and heart disease have nothing to do with inflammation, chronic or otherwise.

Actually, atheroma [wikipedia.org] , the cause (in nearly all cases) of coronary artery disease, and the single commonest cause of death in the Western world, is well established to be an inflammatory process. The process of developing atheroma is influenced by a number of risk factors (e.g. diabetes, hypertension, hyperlipidaemia, smoking, obesity, family history); interestingly, rheumatoid arthritis is also a significant risk factor. It has even been hypothesised that various bacterial infections (which cause inflammation) may be a cause or risk factor for atherosclerosis, though studies looking at antibiotic treatment of these purported infections have not borne this out so far.

Re:Sounds like nonsense (1)

m2943 (1140797) | more than 7 years ago | (#20300675)

In fact, all of those diseases, including cancer, involve some degree of inflammation. And hydrogen peroxide is a key compound in inflammation, basically used as a general purpose "local disinfectant" by the body.

New Light Source (1)

Nom du Keyboard (633989) | more than 7 years ago | (#20295127)

Could this bring about the creation of a hydrogen peroxide fueled flashlight, or area light?

Re:New Light Source (2, Informative)

kebes (861706) | more than 7 years ago | (#20295623)

The short answer is: no.

The paper uses well-established chemistry to generate light-emission. They basically have an ester (peroxalate) polymer with a fluorescent dye (a pentacene derivative). A chemical reaction with hydrogen peroxide (H2O2) changes the peroxalate groups into dioxetanedione groups. This irreversible chemical reaction leads to excitation of the fluorescent dye, and hence light emission.

The hydrogen peroxide is not really the energy source for the luminescence: it is more like a catalyst that enables the peroxalate groups to convert and thereby generate light. For use in a light-emitting device, you would need a large amount of peroxalate in addition to the hydrogen peroxide. Since the peroxalate is used up, you'd have to keep replenishing it.

Basically, there are easier (cheaper) ways to generate light!

However as a diagnostic tool this is great. The paper describes the use for medical imaging, but I see no reason why this couldn't be used for detecting peroxide in other situations, such as for forensics or detecting industrial leaks or contamination. (Then again, in non-medical contexts there are probably existing detection techniques that I'm not aware of.)

The actual reference... (5, Informative)

kebes (861706) | more than 7 years ago | (#20295129)

The press release [gatech.edu] from Georgia Tech has a bit more information. The paper of this work will appear in the October issue of Nature Materials, but is already available online (for subscribers only, unfortunately):
In vivo imaging of hydrogen peroxide with chemiluminescent nanoparticles [nature.com] Dongwon Lee, Sirajud Khaja, Juan C. Velasquez-Castano, Madhuri Dasari, Carrie Sun, John Petros, W. Robert Taylor & Niren Murthy. Published online: 19 August 2007; doi:10.1038/nmat1983 [doi.org]

The paper describes the advantages of their nanoparticles:

The peroxalate nanoparticles have several attractive properties for in vivo imaging, such as tunable wavelength emission (460-630 nm), nanomolar sensitivity for hydrogen peroxide and excellent specificity for hydrogen peroxide over other reactive oxygen species.
In the paper, they demonstrate the use of this photo-marker in live mice, and are able to image the location of hydrogen peroxide anywhere in the mouse body. An obvious question regarding the technique is the toxicity of the nanoparticles. They do not discuss this in the paper (it will probably be the subject of an upcoming study), but the particles are ester polymers, with embedded dye (a pentacene derivative). So they are not using heavy-metal nanoparticles: these are peroxalate polymers. I'm not an expert in biocompatibility, but from the chemical structure, I wouldn't expect it to be highly toxic (it probably even degrades in the body).

Obviously a detailed toxicity study would be required before use in humans. However it's possible that it could be rapidly adapted to ex-situ diagnostics (e.g. on tissue explants) and then be adapted to live in-situ imaging if/when it is determined to be safe.

chemiluminescence / in vivo imaging (1)

bodrell (665409) | more than 7 years ago | (#20298863)

In the paper, they demonstrate the use of this photo-marker in live mice, and are able to image the location of hydrogen peroxide anywhere in the mouse body.
I see you've posted several times for this discussion, and that you've actually read the paper. As you pointed out earlier, pentacene is a fluorescent dye. However, that fact is misleading since its fluorescent properties are not utilized for this application. But what can you expect from a science blurb? They also spelled ester [wikipedia.org] as esther [wikipedia.org] , so I can't expect them to have their chemistry straight.

Anyway, I just wanted to point out that in-vivo imaging is already done on mice using actual fluorescence rather than chemiluminescence (long-wavelength dyes, which emit between about 650-800 nm, are best). Enhanced Raman spectroscopy using metal nanoparticles (SERS) has also been used for in vivo imaging of mice, and I believe it has better tissue penetration. However, the size of the animal is crucial for all these in vivo techniques--being able to see through a mouse is cake compared to a human being (or horse, cow, elephant, whatever).

What I can't wait for is (3, Interesting)

Travoltus (110240) | more than 7 years ago | (#20295139)

a Nanobot that blacklists certain virii and bacteria and kills them on sight.

It should be a simple enough function and if it terminates after a few hours everything should be okay.

That would utterly rock - no more ineffective drugs with side effects.

Re:What I can't wait for is (2, Interesting)

Thyamine (531612) | more than 7 years ago | (#20295371)

Sounds cool, except that I don't think they can perfect the no 'side-effects' part. Walk by the old leaky microwave in grandma's kitchen and suddenly all the nanobots begin to think that you are on their blacklist.

'Oops, my arm just fell off. Better check on what the heck those nanobots are up to today.'

For you and Faylone and BlueZhift (1)

Travoltus (110240) | more than 7 years ago | (#20300095)

First of all, WHY WAS BLUEZHIFT MODDED DOWN??? Jeez. Corporations buy up patents and lock up competing technology all the time. Hello, electric cars?

Thyamine:
That's why I feel nanobot therapy should be restricted to the hospital in a safe environment where bots can't be screwed up by outside energy.

Faylone:
Why would this therapy damage your white blood cells?

Re:What I can't wait for is (1)

Faylone (880739) | more than 7 years ago | (#20295391)

Yeah, please don't go trying to patent that. I rather like my white blood cells.

Re:What I can't wait for is (0, Flamebait)

blueZhift (652272) | more than 7 years ago | (#20295495)

That would utterly rock - no more ineffective drugs with side effects.

This of course raises the question of whether the drug companies that benefit from the current crop of drugs will stand for this. I imagine the smart ones are already working on nanoparticle based drug solutions. But truly effective drugs might not be so good for the bottom line! Nahhhh, no one would be that evil, riiiiiight?

Re:What I can't wait for is (1)

oncehour (744756) | more than 7 years ago | (#20299313)

Well, they could always move it to a subscription model. Pay $X per month that the nano particles are in you. Wouldn't surprise me to be honest and would be perfectly profitable.

Re:What I can't wait for is (4, Insightful)

Rakishi (759894) | more than 7 years ago | (#20295769)

Bacteria and viruses evolve, very very quickly in some cases. There is a reason the immune system can't stop all infections despite it's rather interesting complexity. The worst effect is of course false positives, losing all your neurons to a confused nanobot is not a fun thing.

Re:What I can't wait for is (1)

wtansill (576643) | more than 7 years ago | (#20297475)

Bacteria and viruses evolve, very very quickly in some cases. There is a reason the immune system can't stop all infections despite it's rather interesting complexity. The worst effect is of course false positives, losing all your neurons to a confused nanobot is not a fun thing.
Isn't reading /. pretty much equivalent? Neuron-wise, I mean?

Sounds like MS (myelin attack) (1)

crovira (10242) | more than 7 years ago | (#20298693)

The only difference I can see between your nanobot and my immune system is that its already happening to me.

Can It Diagnose: (-1, Offtopic)

Anonymous Coward | more than 7 years ago | (#20295269)


Organized Crime [whitehouse.org] ?

Not a tricorder.... (3, Interesting)

NIckGorton (974753) | more than 7 years ago | (#20295741)

Um, we can already detect inflammation. Try a technetium-111 or indium-99 labeled WBC scan.

I doubt that this would be specific enough (and of uncertain sensitivity) to be useful. How many false positives and false negatives would you get? It might end up being helpful in situations where you are looking to diagnose a suspected disease, but something this non-specific does not seem like it would be a good screening tool.

A few years back they were hawking full body (or if you were cheap partial body) CT scans as a screen. The brochures would show you the 38 year old mother of two whose renal cell carcinoma was detected and removed when it was 1cm in size, thus saving her life. They did not show you the guy who had a nodule detected on CT that looked suspicious, required a biopsy that caused a pneumothorax requiring a chest tube, that caused him to have a pneumonia with empyema, which caused respiratory failure, which caused him to be intubated for two weeks, needing a tracheostomy, etc.... to diagnose the totally benign lesion he had since he was born.

I wouldn't bet on this as the medical tricorder they are making it out to be.

Re:Not a tricorder.... (1)

kebes (861706) | more than 7 years ago | (#20296025)

I doubt that this would be specific enough (and of uncertain sensitivity) to be useful.
The paper [nature.com] goes into details of sensitivity and specificity. With regard to sensitivity they state:

The peroxalate nanoparticles were also capable of detecting hydrogen peroxide at concentrations as low as 250nM (Fig. 2b), and thus can detect hydrogen peroxide at physiologically relevant concentrations.
With regard to selectivity, they emphasize:

Another appealing feature of peroxalate nanoparticles for imaging hydrogen peroxide is their specificity for hydrogen peroxide over other reactive oxygen species.
Among the quantifications of this selectivity, they explain:

The specificity of peroxalate nanoparticles containing rubrene to hydrogen peroxide was therefore investigated. Figure 2d shows that peroxalate nanoparticles have considerable selectivity for hydrogen peroxide over other reactive oxygen species. For example, at 10 micromolar hydrogen peroxide, peroxalate nanoparticles gave a chemiluminescent intensity of 1.3×106 RLUs^-1, which is 50 times higher than with either tert-butyl peroxide or the hydroxide radical.
I'm not an expert in medical imaging, but a 50-fold selectivity and nano-molar detection limit seem medical usable. No doubt other techniques for detecting inflammation already exist, but this technique may be a useful addition to the diagnostic toolbox.

Re:Not a tricorder.... (1)

NIckGorton (974753) | more than 7 years ago | (#20300105)

I'm not an expert in medical imaging, but a 50-fold selectivity and nano-molar detection limit seem medical usable. No doubt other techniques for detecting inflammation already exist, but this technique may be a useful addition to the diagnostic toolbox.
You are talking about something entirely different. When you talk about the sensitivity and specificity of a medical test that refers only to ratios of true/false positives/negatives. The sensitivity is 'of people who have the disease, how many will have a positive test?' The specificity is 'of positive tests, how many people have the disease.'

This would be (like many tests for general things like a WBC scan) would likely have a very low specificity (too many false positives). That in and of itself is not necessarily a deadly failure in a screening test. Pap smears are a good example of a test that is not very specific, but is a good screening test because it is quite sensitive. So if you have positives on the pap, you go for a test with better specificity like colposcopy.

A good screening test has a high sensitivity for a specific disease that is amenable to treatment (like pre-cervical cancer, or hypertension, or diabetes), and that is cheap enough to do in a society-wide level (like checking a BP or a blood sugar or pap - all of which are dirt cheap). I am guessing this will be slightly less than a gazillion dollars, so it sounds like it would be a quite craptastic screening tool from TFA's description.

Re:Not a tricorder.... (1)

Hafnia (590482) | more than 7 years ago | (#20296509)

You got the numbers wrong , it's Tc-99m and In-111. And the problem with CT has never been about wrong diagnoses , or bad treatment , the problem is the radiation induced cancers. CT (and any other X-ray procedure) uses ionizing radiation and WILL statistically induce cancers in a number of patients. A problem that is also present with the mentioned Nuclear Medicine isotopes. Though on a much smaller scale since the energies are smaller and more specific. This nano-thing is very interesting because you can avoid ionizing radiation , but if it turns out to be toxic ....... well , nothing is free ;-)

Re:Not a tricorder.... (1)

NIckGorton (974753) | more than 7 years ago | (#20300293)

It is not CT scans that I am saying are the problem. It is indiscriminate use of diagnostic tests as screening tests. The risk of doing the wrong test is far greater than people think. And the functional characteristics of tests (the positive and negative predictive values) change with use in different populations.

Take for example an HIV test that is 99.9% specific and 100% sensitive. That is, of 1000 positives, 999 are true positives. Sounds like a good test, right?

Well it depends....

Use the test in an urban population of men who have sex with men and IV drug users (with a high prevalence of HIV) and its a great test. Use it in a nursing home population in Kansas, and it sucks ass. (And please before you label me homophobic... I'm a gay physician that practices in northern California. Lets not go there, kay? And no the numbers below are not accurate... but they are round and therefore will be used because as you figured out, I suck ass with numbers. I have to wear a calculator watch to work.)

So, we test 1000 inner city MSMs and IVDAs, of whom 5% have the disease. We get 50 true positives, and in a population of 1000, we get 1 false positive (since its 99.9% specific.) Not bad, one guy has to sweat it out till the confirmatory test, but that's a pretty good test (better than most tests we have, BTW.) So then we go to Kansas and test 1000 nursing home patients who have a prevalence of 0.1%. So we get one true positive, and out of 1000 one false positive. Pretty crappy predictive value since half the positive test results you get are false positives.

If you get a positive in the first population, there is a 98% chance its a true positive. If you get a positive in the second population with a lower prevalence of the disease, then the chance you actually have the disease is much lower (50:50.)

It works the same with all tests... if you have a low prevalence of disease, you will get more false positives. If you have a population of young 'worried well' folks (i.e. many of the people who opted for full body CTs) the test has worse performance because more of the positive results will be false positives.

And yes, radiation is bad too. But I would rather have several CTs than take the risk of getting an invasive work-up like an open lung or liver or kidney biopsy. However, when necessary, radiography is important. If you have a 10% chance of having appendicitis - getting a CT may be better bet than either sitting on it (and risking perforation) or going to the OR for the stomach flu. If your odds of appendicitis are greater... say 90%, I would opt with the operative exploration. If you odds are 1%, go home and come back if you get worse. It all depends on the clinical scenario - which is why tests like the full body CT (or other diagnostic tests used for inappropriate screening) are a menace.

Re:Not a tricorder.... (1)

Hafnia (590482) | more than 7 years ago | (#20308709)

I don't disagree with you about the concept of screening healthy people, in most cases, it's a bad idea.
But don't tell me somebody have been using CT for screening - was that in the US ?
I live in Denmark where there was a minor debate a couple of years ago regarding screening mid-aged women for brest cancer. Your exact argument was the primary reason a lot of doctors opposed the idea. But even if they use X-ray for screening it's nowhere near as risky as doing full body CT. And the primary proponent of the screening was suggesting Ultrasound as the screening technique - which makes sense since modern ultrasound is almost as accurate , and in some cases more accurate, than X-ray mammography.
BTW i'm not at all against X-ray for diagnostics , and i'm not really concerned about the radiation hazard if the doctors believe it's nescessary - the risk is small. But full body CT for screening is crazy !!

Re:Not a tricorder.... (1)

NIckGorton (974753) | more than 7 years ago | (#20310555)

"I don't disagree with you about the concept of screening healthy people, in most cases, it's a bad idea."
Its not that screening is a bad idea. Its that BAD screening is a bad idea. Medical screening (like for hypertension, diabetes, obesity, depression, alcoholism, certain types of cancer like cervical, breast, colon, domestic violence, etc) is a GREAT idea and has saved the lives of millions. However, for a test to be a valid and good screening test, it much meet some very specific criteria. The ultimate question is: does it save more active, quality years of life than it costs for a decent price?

"But don't tell me somebody have been using CT for screening - was that in the US ?"
Yep, though not exclusively. Fortunately it has fallen out of favor in the US, but is used in other countries - often for medical tourists. http://www.fda.gov/cdrh/ct/ [fda.gov]

"I live in Denmark where there was a minor debate a couple of years ago regarding screening mid-aged women for brest cancer. Your exact argument was the primary reason a lot of doctors opposed the idea. But even if they use X-ray for screening it's nowhere near as risky as doing full body CT. And the primary proponent of the screening was suggesting Ultrasound as the screening technique - which makes sense since modern ultrasound is almost as accurate , and in some cases more accurate, than X-ray mammography."
That debate was probably around screening for women aged 40-50. There is solid evidence that the benefits of mammography outweigh the risks in women over age 50, while the evidence for women 40-50 is less certain. The big issue is whether the (small but real) net benefit is worth the financial cost. For example, in women of average risk if you did mammography only every 2-3 years over 50 rather than yearly and put the money saved into prevention and treatment of alcohol, drug, and tobacco abuse, you would save far more lives with the same amount of money.

However, often it is the case that money is allocated based on who has better lobbying power and who is seen as 'more deserving.' For example, worldwide research money favors type 1 diabetes (about 5-10% of diabetics) rather than type 2. This is because the parents of kids with Type 1 are hella better at lobbying for funds, and overall people feel more sympathy for a kid who got type 1 diabetes at six than a morbidly obese type 2 diabetic who people perceive as having caused his own disease by gluttony. So in the case of mammography vs drug treatment funding - women who had/have breast cancer are better at lobbying and garner more sympathy than people with drug, alcohol or tobacco addiction who are (again) seen as having caused their own problems. So guess where the money gets spent?

And this is not simply a US phenomenon - for a good example of how these politics get played out, look at the coverage for Herceptin in the UK's NHS: http://www.bmj.com/cgi/content/full/333/7578/1118 [bmj.com] For every one woman with early stage breast cancer saved it will cost over a million US dollars (which might save dozens of people if spent on other less expensive cancer therapies.)

With regard to ultrasound's performance, its not a good screen. It is a good diagnostic test in women who have clinically apparent lumps (especially those who are younger.) But as a screen it is neither as effective nor as consistent (its effectiveness varies considerably between different US techs.) A better (and minimally safer) method is MRI - but again it would cost a gazillion dollars, so its crappy as a screen.

h2o2 is beneficial (1)

nido (102070) | more than 7 years ago | (#20295811)

hydrogen peroxide (thought to be overproduced in trace amounts in the early stages of most diseases that involve some sort of chronic inflammation in the body)
I wouldn't say that it's "overproduced". Seems that the body creates hydrogen peroxide as a way to deal with certain problems. See The Many Benefits of Hydrogen Peroxide [educate-yourself.org] , or Intravenous Hydrogen Peroxide Therapy [med-library.net] .

Scarry Sources (0)

Anonymous Coward | more than 7 years ago | (#20297335)

At least give us legitimate sources, not someone hawking supplements.

Next step (1)

El_Smack (267329) | more than 7 years ago | (#20295953)

Sounds good. Can't wait till we invent a salt shaker that can detect the hydrogen peroxide for quick, mobile diagnosis!

Proctologists will discover... (1)

rholland356 (466635) | more than 7 years ago | (#20297633)

Proctologists using the new nanoparticle will discover the sun really does shine out your ass.

Nanoparticles? (0)

Anonymous Coward | more than 7 years ago | (#20297859)

Can anyone tell me why we keep talking about "nano..." things rather than "molecules" or "compounds"?

I can't think of many situations off the top of my head where "nanoparticle" etc. adds something that would be lost by saying either molecule or compound, whichever is appropriate for a given situation.

Duh ... (0)

Anonymous Coward | more than 7 years ago | (#20300303)

It's been known since the 1950's (and quite possibly earlier) that a variety of molecules exhibit a chemiluminescence in the presence of even very low concentrations of peroxides. For instance, a heme molecule -- think hemoglobin or myoglobin. Hell, I even used this sort of reaction for quantitating hydrogen peroxide in my research back in the 1970's.

If there's ANYTHING new here, it's in the incorporation of a detector molecule into a nanoparticle. But, that's hardly a new idea, now is it?

Don't worry baby (1)

tsotha (720379) | more than 7 years ago | (#20301363)

It always glows like this. At least, after my trip to Amsterdam.
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