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From google:

http://www.medgadget.com/2015/...

The base-pair sequence of DNA determines its biological function. As you say, this sequence determines what kinds of proteins get made, including their exact shape (and more broadly how they behave).

But TFA is talking about the conformation (shape) of the DNA strand itself, not the protein structures that the DNA strand is used to make.

In living organisms, the long DNA molecule always forms a double-helix, irrespective of the base-pair sequence within the DNA. DNA double helices do actually twist and wrap into larger-scale structures: specifically by wrapping around histones, and then twisting into larger helices that eventually form chromosomes. There are hints that the DNA sequence itself is actually important in controlling how this twisting/packing happens (with ongoing research about how (innapropriately-named) "junk DNA" plays a crucial role). However, despite this influence between sequence and super-structure, DNA strands essentially are just forming double-helices at the lowest level: i.e. two complementary DNA strands are pairing up to make a really-long double-helix.

What TFA is talking about is a field called "DNA nanotechnology", where researchers synthesize non-natural DNA sequences. If cleverly designed, these sequences will, when they do their usual base-pairing, form a structure more complex than the traditional "really-long double-helix". The structures that are designed do not occur naturally. People have created some really complex structures, made entirely using DNA. Again, these are structures made out of DNA (not structures that DNA generates). You can see some examples by searching for "DNA origami". E.g. one of the famous structures was to create a nano-sized smiley face; others have 3D geometric shapes, nano-boxes and bottles, gear-like constructs, and all kinds of other things.

The 'trick' is to violate the assumptions of DNA base-pairing that occur in nature. In living cells, DNA sequences are created as two long complementary strands, which pair up with each other. The idea in DNA nanotechnology is to create an assortment of strands. None of the strands are perfectly complementary to each other, but 'sub-regions' of some strands are complementary to 'sub-regions' on other strands. As they start pairing-up with each other, this creates cross-connections between all the various strands. The end result (if your design is done correctly) is that the strands spontaneously form a ver well-defined 3D structure, with nanoscale precision. The advantage of this "self-assembly" is that you get billions of copies of the intended structure forming spontaneously and rapidly. Very cool stuff.

This kind of thing has been ongoing since 2006 at least. TFA erroneously implies that this most recent publication invented the field. Actually, this most recent publication is some nice work about how the design process can be made more robust (and software-automated). So, it's a fine paper, but certainly not the first demonstration of artificial 3D DNA nano-objects.

As outlined here, it is the retinal pigmented epithelial (RPE) cells and/or photo-receptors that are being grown and transplanted here. The RPE cells are the supply source for the photo-receptors and comprise the far rear layer of the retina (the neurons of the retina are supplied by blood vessels at the front which you're looking through right now). The photo-receptors, while technically sensory neurons, don't project very far, so replacing them could conceivably restore sensitivity without disrupting the neural connections of the retina. Growing them with the proper alignment to the optics of the eye might be a challenge, though.

Replacing the whole retina is not yet feasible. The ganglion cells project through the optic nerve all the way to the middle of the brain - you can't just swap these out. The other neurons (amacrine, bipolar, horizontal, etc.) of the retina form very specific types of connections during development, and simply replacing these with new cells won't restore such connections. The RPE cells and photo-receptors are about the only thing that might be replaced to restore some lost sensitivity, and are also the easiest to reach surgically, being near the back.

It'll be interesting when people start getting this surgery as a performance enhancing drug.

Though, I worry about the "drive by" hackings.

My bad, it's 11T. See links below for info.

This is the existing 9T MRI with 80cm bore.

http://medgadget.com/2007/12/94_tesla_monster_mri.html

This is the whole-body 11T MRI being built

http://irfu.cea.fr/en/Phocea/Vie_des_labos/Ast/ast_visu.php?id_ast=3058

Some of the underlying technology:

http://www.microwavejournal.com/articles/print/2551
http://www.microwavejournal.com/articles/10402-software-platform-for-mri-phased-array-system-design-optimization
http://www.hfmmagazine.com/hfmmagazine_app/jsp/articledisplay.jsp?dcrpath=AHA/PubsNewsArticleGen/data/0403HFM_NEWS_Construction
http://www.aapm.org/meetings/05am/pdf/18-2826-94182-387.pdf

I think it's -possible- that garage molecular biology research is just around the corner. I wasn't around for the era of kids in their garages with a computer leading to million dollar startups, but it seems to me like it's going to happen with DNA.

Affordable PCR machines, or DIY PCR machines are starting to appear, fully sequenced genomes are of course available freely online. Anyone with half a brain can design primers and amplify DNA, anyone with a little patience can make any construct they want.

At the same time, DNA constructs are commercially available, and it's not too hard to see that the prices are inflated. The FUCCI cell cycle indicator is pretty cool, with a decent microscope, you can watch cell cycles. FUCCI is basically genes found in nature stitched together, but to buy the constructs, you'd need to shell out nearly a thousand dollars (maybe the price has come down, it's been a while since I looked into it.)

This seems like a pretty similar situation to music in the napster area: the path of least resistance to acquiring it is ignoring any copyright protections on this stuff. It's not too terribly complicated to make FUCCI yourself using PCR and some enzymes. I'm aware that copyright law and DNA hasn't been completely settled yet, but it's worth thinking about now in my opinion.

I think there's a real danger that companies who hold copyrights on DNA are going to try to enforce them by taking draconian measures. Something like DRM might be invented for DNA sequences I suppose, but I doubt that would even work as well as DRM on music. Instead what I think they'd do is try to kill off the home biology research field before it starts. And I think they'd point to stuff like this to justify it. "We can't have people building their own PCR machines: THEY'LL MAKE SUPERFLU! So please pass the protect life act, which stipulates that no company shall sell PCR primers for copyrighted DNA sequences."

It's possible I'm buying trouble, and am just overly cynical about corporations using laws to enrich themselves by limiting progress. Still, I'd hate to see biological research be stifled any further by copyright law.

270 dpi is "retina" now? Well, shoot, I didn't realize they lowered the standard for "retina".

Well first, Retina was a marketing term. The marketing was that the resolution was higher than the eye's ability to discern the pixels. A tablet will likely be held a little further away than the one foot distance that Apple claims an iPhone is held from the face. Holding the tablet 14" instead of 12" away would be the same effective resolution

http://medgadget.com/2010/06/apples_retina_display_what_does_it_mean.html

Not sure of the state of this technology for humans because I'm sure it's stifled by religious politics (I do know it is used for certain species of endangered shark), but why adopt or take the risk of a donor womb when an artificial uterus would solve the problem? 9 months of extra freedom, no risk to the mom's life, and no hormonal baby blues (unless she takes hormones to lactate) - it seems like the way to go.

My wife and I decided not to have kids, partially because we both have bad genetic issues, so I personally don't really have any issues with genetic engineering that is used to fix genetic problems. Playing God is the last thing I worry about - God (belief issues aside) failed to create a perfect human or else allowed others (e.g. Satan) to create flaws in us and therefore is fallible (why would he allow that?), and therefore I think we should be able to fix the flaws.

This is beyond the theoretical limit of optical microscopy." So either the scientists are lying, or the theory is wrong. Which is it? Pons? Fleischmann? Anyone?

The dumbed down version (the only one I understand): light has a "size" of about 200 nanometers, and you wouldn't expect to see detail smaller than that using light. Recently though, people have found a way around that.

This actually isn't the first microscope to break that barrier. There's OMX for one.

The classification as "medical devices" by the FDA is what attaches the requirement of a prescription.

A quick google brought this up: http://medgadget.com/archives/2005/08/contact_lenses_1.html

So ... since 2005 this has been the case for contacts.

P.R. Alert: This Slashdot story is a public relations release. The misleading Slashdot summary says, "Other sources have picked up the story...". In reality, they are inserting press releases everywhere they can, and the kind of work being done is not new.

It was proven long ago that dogs can smell chemicals associated with cancer. For example, see this 2006 article in National Geographic News, Dogs Smell Cancer in Patients' Breath, Study Shows. That's part of what started the present interest in making a machine to detect cancer.

This February 2007 article is more interesting: Compact lung-cancer breath test may be possible. Quote: "The test uses 36 chemical dots that react to telltale compounds in a person's breath. The dots change colour when exposed to compounds that signify the presence of lung cancer."

This February 2007 article gives more information about how it is done: US Scientists Prototype Breath Test For Lung Cancer

Even Oprah's magazine had article in June 2009 about dogs sniffing cancer and making machines to imitate dogs: Sniffing Out Cancer. Quote: "The researchers are collaborating with scientists at the University of Maine, who are trying to mimic the dogs' cancer-sniffing abilities with laboratory machines." Another quote: "So far, the Pine Street Foundation dogs have done 25,000 scent trials for ovarian cancer."

Slashdot: Not quite as current as Oprah? Old news for nerds who were playing video games and wouldn't know the difference?

Many researchers are doing similar work. For example, see the February 2008 article, The Cancer Breathalyzer. Quote: "Dr Yousef ... believes that the breath test will provide a more convenient and rapid method for diagnosing serious diseases than blood or urine analysis, and will require minimal medical intervention."

Other researchers are studying the possibility of using blood tests to detect cancer. See the December 2007 article, Study points to possibility of blood test to detect lung cancer.

Here is a November 2005 research paper that surveys some of the issues of early detection of cancer: The Progress and Promise of Molecular Imaging Probes in Oncologic Drug Development.

He's actually starting to have trouble communicating, as the movements he used for it back then (blinking I think?) are starting to become harder.

Perhaps the next step would be to monitor his brain waves. I don't know what the progress is in passive external electrodes, but fMRI has achieved some amazing things, like like Voice recognition software reads your brain waves . This article is about decoding what people are listening to or looking at - maybe because it's easier to correlate experimentally - rather than what they want to communicate, but perhaps looking at other regions of the brain might achieve the latter. I think I've read something about being able to detect whether a person is telling the truth (kind of eerie). There's also the problem of the huge size of the machines, although there's some work on handheld fMRI (from 2005, not sure of the current state of the art).

I was able to sit in on an open heart surgery at one point in my life. After the surgeon cracked the chest open, he inserted a surgical glove full of (I think) normal saline, tied off at the wrist. Called it a 'helping hand'. The heart continued to beat merrily away on top of it, and they used a device called an octopus to hold the pertinent section of the heart still.

To date, remains one of the coolest things I have ever seen.

"The organisms that survive this defense generally do it by preventing the host's cells from exposing them to the radicals, and not by having a resistance to the radicals themselves. (I'm not aware of any that withstand radicals, but I'm willing to be informed)."

Deinococcus radiodurans can withstand hydroxyl and superoxide radicals inside itself. These things can withstand extremely high doses of ionising radiation, UV light, hydrogen peroxide, and desiccation by freeze-drying:

http://medgadget.com/archives/2007/03/the_secrets_of.html

I wonder what would happen if the magnetic pulses were applied to more important sections of the brain, such as the area that controls autonomous bodily functions, like the heart. I suppose, if it is capable of knocking out the area of the brain that controls speech, it should be capable of knocking out the section of the brain that controls other, critical bodily functions. Is it only me, or do you see a potential weapons application for this in the future?

One thing to know about TMS is that 90-95% of the labs doing research with it use coils which are only capable of stimulating ~1-2cm deep, which is really only useful for hitting cortical areas (or cerebellum). Autonomic functions are controlled by subcortical brain regions, farther away from the scalp. There are a few labs however working with developing things like Deep TMS which should hypothetically be able to hit deeper regions, but I've never worked with those systems, so I don't know what sorts of safety measures they take.

like this?

There seem to have been a rash of health-related stories lately...

I'm a doc, but from the article I have no good idea what this thing does. Sound waves to reconstruct pictures... well, this is called an ultrasound, as somebody already pointed out. Air is a really terrible conductor of ultrasound waves, so usually you'd get a black picture if you just used a u/s probe (that's why they use that goop to do ultrasounds on pregnant women.) True, with a pneumonia, you'd get a denser view, but a regular stethoscope will also tell you that.

Ok, maybe it takes the sounds it hears, and displays a histogram of intensity versus time. Well, this is called a phonocardiogram (phonogram), done for years, and HP and others even has a stethoscope that can do that. http://medgadget.com/archives/2005/05/androscope_i ste.html.

Ok, so maybe it does something more advanced, like using an array of sensors with high temporal (time) resolution with varying assumptions about sound velocity to try to interpolate a sound map of the lungs in space. Thus, low frequency sounds that come from a localized are of the lung could be assigned a color, high frequencies a different color, with the intensity of the color relating to the intensity of the sound... possible.

The things is, this sounds like somebody written by a businessman (not surprising, given the journal) and not somebody with medical knowledge.

From TFA: "Doctors often disagree about what they hear..."

Yes, but what you really care about is disagreeing about the diagnosis. It's rare, given all the tools currently available (CT scan, chest xray, good ol' fashioned stethoscope, what the patient tells you). I'm just not sure how this tool would help.

From TFA: "Kushnir has long criticized overuse of radiation among doctors."

Ooohh, hold on there... A chest x-ray is about equivalent radiation to 3 days on the beach, or a couple-hour flight (due to cosmic rays.) You don't see airline stewardesses with a lot of cancer. A CAT scan is considerably more radiation, though.

I'd like to sit down to a presentation / demonstration of the technology, but I doubt that this guy would get time in our hospital, as they seem more focused on taking the company public and making big bucks. I like to read about new technology in reputable medical journals, not Businessweek.

P.S. Last time I wrote to defend HP, people called me a corporate shill. This will show them! :p Man, some slahsdot posts can be pretty poor.

Comany website:

    http://www.deepbreeze.com/

Multimedia:

    http://medgadget.com/archives/2007/07/video_of_vri xp_system_from_deep_breeze.html
    http://www.medgadget.com/archives/2007/07/new_pulm onary_imaging_modality_approved_by_the_fda.html
    http://www.thieme.de/viamedici/aktuelles/wissensch aft_archiv1/0000001_digitales_stethoskop.html

Comany website:

    http://www.deepbreeze.com/

Multimedia:

    http://medgadget.com/archives/2007/07/video_of_vri xp_system_from_deep_breeze.html
    http://www.medgadget.com/archives/2007/07/new_pulm onary_imaging_modality_approved_by_the_fda.html
    http://www.thieme.de/viamedici/aktuelles/wissensch aft_archiv1/0000001_digitales_stethoskop.html

Here, too: http://medgadget.com/archives/2007/07/video_of_vri xp_system_from_deep_breeze.html

More information and better reporting here:

http://medgadget.com/archives/2007/01/second_sight _me.html
and
http://www.theregister.co.uk/2007/02/16/retinal_bl indness_implant/
and
http://www.technologyreview.com/Biotech/18193/page 1/

"Researchers have also uncovered an Ancient Egyptian mandible, dated to approximately 2750 BC, having two perforations just below the root of the first molar, indicating the draining of an abscessed tooth. Recent excavations of the construction workers of the Egyptian pyramids also led to the discovery of evidence of brain surgery on a labourer, who continued living for two years afterwards."
"The Edwin Smith papyrus is the oldest known surgical text, dating back to the 1600s BC, although it contains information dating back to 3000 BC. It is an ancient Egyptian textbook on surgery, and describes in exquisite detail the examination, diagnosis, treatment, and prognosis of numerous ailments."

http://www.medgadget.com/wiki/wiki/Surgery

It is a medical Wiki page, so believe at your own risk...

actually, i have been trying to find a doctor willing to implant a bone anchored hearing aid (baha) for quite some time. the biggest problem is that i don't have a hearing problem. about the best advice i've gotten from just about anyone i've asked (from transhumanists to singulatarians), is to try and go overseas. i'd prefer tokeep it in the u.s., but if it comes down to it i'll end up doing just that...

i'm surprised that they are so leery about performing an operation i'm completely comfortable paying for, even if i sign any waivers that might be needed to protect themselves with.

in the end, all i want is a 3mm titanuim screw implanted into the mastoid bone behind my jaw. does anyone know of where i might be abel to get one of these? i've seen bone spikes, coral implants, glass beads and all sorts of things, but i've had very little luck finding anything thats not just cosmetic.

medgadget was even nice enough to give me a small writeup last year.

if any of you can help, it would be greatly appreciated.

Become a ... doctor, whatever

Umm, no.

http://www.msnbc.msn.com/id/4946229/
http://www.news24.com/News24/Technology/News/0,,2- 13-1443_1824893,00.html
http://www.medgadget.com/archives/2006/04/very_rem ote_rob.html
http://www.highbeam.com/doc/1G1:143341452/Long-dis tance+doctor~R~(usage+of+robotics).html?refid=SEO
etc.

The prime reason why HCI (aka "GUIs") is in such a poor shape is that each application still controls its own GUI.

New OSes have little opportunity for HCI improvements because too many of the details are left down for the application programmers to decide upon. At best, the OS vendor provides a shared GUI library (buttons + widgets), and a guidebook teaching app authors the "right" way to do it.

But, depending on each individual author to carry out the instructions is fundamentally limited and slow. Not every programmer will be aware of the guidelines, choose to obey them, or be capable of following it exactly even if he tries.

And even if all coders were magically obedient to the published standard, it's still non-optimal. New ideas to improve the HCI guidelines cannot be uniformly implemented without waiting years for all programs to be updated. Computers are supposed to REDUCE redundant labor- instead of each app's GUI being written separately, all trying to implement the same guidelines, one piece of code should handle all that functionality in one place. Code reuse is a fundamental rule of software design that has taken far too long to penetrate the HCI world.

What we need are applications written to a high level GUI description service, so that the OS can implement a UI consistent with other programs and exactly tailored to the limitations of this user (Colorblind? Blind? No keyboard? No mouse? No muscular control besides blinking?)

And this one seems more advanced and ready for use:
http://www.medgadget.com/archives/2005/05/capsule_ endosco.html

Peizo printer head technology was picked up by the automotive industry and modified to create the newest generation of fuel injectors.

This device is basically a mini fuel injector -- just replace the fuel with medicine.

The problem with this is that there are already purley mechanical devices that do the same thing:
http://www.medgadget.com/archives/2005/03/vitajett m_3.html