VIOlight is a portable toothbrush sanitizer, for travel and home use:

VIOLight sanitizes your toothbrush and prevents contamination build-up. Even after a thorough rinsing, thousands of germs can remain on your toothbrush, creating the potential for harmful bacteria to grow. In just minutes, VIOLight sanitizes your toothbrush with UV light. After each use, place your toothbrush in the battery-operated case; the UV bulb automatically shuts off after the sanitation cycle is done. Case has a removable tray that stores the brush until your next use. Bulb lasts 1,000 hours.

Product page...

(hat tip: OhGizmo!)

Gizmodo reports:

Ever wanted to take a bath while wearing your electrocardiograph? Or did you ever just want to see how your body reacts to taking the plunge into a tub of cold pudding? Or do you really not care and are reading this instead of doing end-of-year reports? Well, you're in luck! Fukuda Denshi Co. in Japan has started selling a portable, waterproof electrocardiograph that can be worn while the user takes a bath and records your physical condition on the fly.

The device seems to be a home monitor, simple and likely "not for diagnostic purposes." Interesting nonetheless.

Researchers from the Howard Hughes Medical Institute have discovered a molecular link between a high-fat diet and type 2 diabetes. The group of scientists from University of California, San Diego, together with their colleagues at Kirin Brewery Co. Ltd., and the University of Fukui (Japan), have showed that a high-fat diet disrupts genetic mechanisms behind insulin production:

In an article published in the December 29, 2005, issue of the journal Cell, the researchers report that knocking out a single gene encoding the enzyme GnT-4a glycosyltransferase (GnT-4a ) disrupts insulin production. Importantly, the scientists showed that a high-fat diet suppresses the activity of GnT-4a and leads to type 2 diabetes due to failure of the pancreatic beta cells.

The detailed explanation of the process is in the press release...

Please note that we now feature del.icio.us feed of bookmarks by our editors (located under the News Feeds). We figured that if it is of interest to us, it might be of interest to you. If you hate it, speak up!

When it comes to mirrors and reflections, humans don't fully understand them, as discovered by researchers from the University of Liverpool:

Dr Marco Bertamini, from the University's School of Psychology, conducted a number of experiments by covering a mirror on a wall and inviting participants to walk along a line parallel to the mirror.

He asked them to guess the point at which they would be able to see their reflection. Results showed that people believe they can see themselves even before they are level with the near edge of the mirror.

Dr Bertamini said: "People tend not to understand that the location of the viewer matters in terms of what is visible in a mirror. A good example of this is what we call the Venus Effect which relates to the many famous paintings of the goddess Venus, looking in a small mirror.

"If you were to look at these paintings, you would assume that Venus is admiring her own face, because you see her face in the mirror. Your viewpoint, however, is rather different from hers; if you can see her in the mirror then she would see you in the mirror."

Participants were also asked to estimate the image size of their head as it appears on the surface of the mirror. They estimated that it would be a similar size to their physical head. However, participants based their answer on the image they saw inside the mirror rather than on the image on the surface of it. They failed to recognise that the image on the surface of the mirror is half the size of the observer, because a mirror is always halfway between the observer and the image that appears inside the mirror.

Link...

The Venus effect images...

This one is from the American Chemical Society: "Natural compound from 'pond scum' shows potential activity against Alzheimer's"

An important study published in the British Medical Journal has found no existing conventional or complementary intervention that is effective for preventing or treating an alcoholic hangover. Too bad.

With the help of a modified atomic force microscope, researchers at the University of California at Berkeley and Stanford University have discovered how the scaffolding matrix of actin within our cells helps them to deal with physical obstacles, allowing cells to propagate, metastasize, and perform such functions as phagocytosis.

From the National Science Foundation website:

To track the growth rate and force generated by actin, the bioengineers modified an atomic force microscope (AFM).

In most research, the business end of an AFM is a miniscule, extremely sharp tip that is attached to a thin silicon-nitride cantilever. Because the tip is so slight, even features as tiny as individual atoms can cause the cantilever to deflect as it passes along, or slightly above, a surface. A laser bounces off the cantilever and into a detector, registering the tiny deflections and providing signals a computer translates into an image.

For this study, the researchers created a specialized AFM that uses two cantilevers and two lasers. Instead of scanning a surface, the cantilevers served as tiny springboards, one to bend as actin grew beneath it and the other to stay as a reference point close to the floor of the sample chamber. Using the two-cantilever system, the researchers pushed longer on the filaments than in any earlier study, and with more force -- in some cases to the point where the filaments stalled and could grow no further.

In multiple experiments, the cantilevers applied an initial force to a slurry of growing actin filaments, then applied a larger force for as long as 30 minutes. They then returned to the original load, at every stage tracking how fast the network grew.

Each time, when the cantilever returned to its original load, the growth velocity of the actin was faster. When the fibers endured multiple load cycles, they grew at a rate that was dependent upon all of the cycles.

"We've found that the growth of actin is dependent on its loading history -- not just on the load it feels at one moment, as we previously thought," says Fletcher. "This means the structure of a cell has some 'memory' of its physical interactions."

The researchers suspect the effect may relate to filament density, and the growth rate may be a function of the network architecture, itself dependent upon the entire load history.

"For a given load, proteins assume a certain network architecture," says Fletcher. "This architecture then remodels under a new load. So, if you go back to the original load, the architecture is still tuned for a higher load, resulting in explosive growth."

More...

The MIT Technology Review publishes its list of biotechnology trends of the passing year: Best in Biotech for 2005.

Researchers from MIT have dispelled a commonly held belief that adult brain cells don't grow, when they discovered remodeling of dendritic arbors in the visual cortex in living mice. The discovery might have future clinical implications.

From the MIT News Office:

The study's co-authors -- Nedivi; Peter T. So, an MIT professor of mechanical and biological engineering; Wei-Chung Allen Lee, an MIT brain and cognitive sciences graduate student; and Hayden Huang, a mechanical engineering research affiliate -- used a method called two-photon imaging to track specific neurons over several weeks in the surface layers of the visual cortex in living mice. While many studies have focused on the pyramidal neurons that promote firing, this work looked at all types of neurons, including interneurons, which inhibit the activity of cortical neurons.

With the help of technology similar to magnetic resonance imaging (MRI), but at a much finer, cellular resolution, the researchers were able to stitch together two-dimensional slices to create the first 3-D reconstruction of entire neurons in the adult cortex. Dendritic branch tips were measured over weeks to evaluate physical changes.

What the researchers saw amazed them.

In 3-D time-lapse images, the brain cells look like plants sprouting together. Some push out tentative tendrils that grow around, or retract from contact with, neighboring cells. Dendrite tips that look like the thinnest twigs grow longer. Of several dozen branch tips, sometimes only a handful changed; in all, 14 percent showed structural modifications. Sometimes no change for weeks was followed by a growth spurt. There were incremental changes, some as small as 7 microns, the largest a dramatic 90 microns.

"The scale of change is much smaller than what goes on during the critical period of development, but the fact that it goes on at all is earth-shattering," Nedivi said. She believes the results will force a change in the way researchers think about how the adult brain is hard-wired.

Nedivi had previously identified 360 genes regulated by activity in the adult brain that she termed candidate plasticity genes or CPGs. Her group found that a surprisingly large number of CPGs encode proteins in charge of structural change. Why are so many of these genes "turned on" in the adult well after the early developmental period of dramatic structural change?

The neuroscience community has long thought that whatever limited plasticity existed in the adult brain did not involve any structural remodeling, mostly because no such remodeling was ever detected in excitatory cells. Yet evidence points to the fact that adult brains can be functionally plastic.

The press release...

The article: Lee WCA, Huang H, Feng G, Sanes JR, Brown EN, et al. (2006) Dynamic Remodeling of Dendritic Arbors in GABAergic Interneurons of Adult Visual Cortex. PLoS Biol 4(2): e29

UK's Engineering and Physical Sciences Research Council is reporting that a novel portable brain scanner, developed at University College London, could aid the treatment of premature and newborn babies in NICUs. The device is an optical tomography system:

Currently, there are two main ways of performing brain scans on small babies. Magnetic resonance imaging (MRI) can provide data on brain function, but MRI scanners are large and static, and the baby may need to be sedated and wheeled to the scanner for the procedure to be carried out. The other alternative, ultrasound, can be performed at the cot side and is effective at revealing brain anatomy, but cannot show how the brain is actually functioning, e.g. in terms of oxygen supply and blood flow.

Combining the advantages of MRI and ultrasound but avoiding their disadvantages, MONSTIR, the first scanner of its kind in the world, uses an innovative technique called optical tomography to generate images showing how the brain is working. In optical tomography, light passes through body tissue and is then analysed by computer to provide information about the tissue.

A helmet incorporating 32 light detectors and 32 sources of completely safe, low-intensity laser light is placed on the baby's head. The sources produce short flashes and the detectors measure the amount of light that reaches them through the brain and the time the light takes to travel. A software package also developed with EPSRC funding uses this information to build up a 3D image. This can show which parts of the brain are receiving oxygen, where blood is situated, evidence of brain damage etc.

MONSTIR is the size of a fridge-freezer and takes around 8 minutes to generate an image. The aim is to produce a version that is half this size, 5 times faster, even more accurate and geared for clinical use. The potential use of the technology in breast imaging to aid cancer prevention and treatment is also being trialled.

Dr Adam Gibson is a key member of the multi-disciplinary MONSTIR team at UCL that includes medics, physiologists and mathematicians. He says: "The technology we're developing has the potential to produce high-quality images at the cot side and is also cheaper than MRI. It could make an important contribution to the care and treatment of critically ill babies. Scanners could be available commercially within a few years."

The press release...

More at University College London Dept of Medical Physics & Bioengineering...

Flashback: Optical Tomography Device to Examine Tissue-Engineered Vessels, Grafts and Valves

Professor Calum McNeil and colleagues at the School of Clinical and Laboratory Sciences at Newcastle University are developing miniaturized gyroscopes that could help to diagnose cancer and aid in its treatment. Gyroscopes--"no bigger than a speck of dust"--will become part of a future generation of biosensors and will function through the identification of cancer specific markers (proteins, DNA sequences or other molecules):

The researchers have manufactured discs less than one-tenth of a millimetre in diameter and coated them with special patterns of DNA or proteins which cause the cancer-specific markers to bind to the surface.

The discs are created in a silicon wafer and made to vibrate electronically in two modes. When a cancer-specific marker binds to the surface of a disc, in the pattern of the coating, the uneven weight causes one of the modes of vibration to change in frequency.

The difference between the frequencies of the two modes of vibration is measured, enabling the detection of tiny amounts of cancer specific marker. In theory, even the weight of a single molecule binding to the surface of a disc could be detected.

The press release...

As the year comes to an end, we would like to present to you what we have accomplished and where we are going next. We would like to showcase the best stories, most interesting devices and the most fascinating discoveries, as selected by us: internet journalists and clinicians, the editors of Medgadget.com.

2005 was an extraordinary year for our website. In the course of the last 12 months, Medgadget was born, and became the most heavily trafficked and linked to medical weblog out there. Thank you, our dear readers!

It is our pleasure to cover the cutting edge of medicine, medical technology and the latest science, and to bring it to you with our clinical perspective. All our news stories are personally selected, cross referenced to their original sources, and many of them have appeared on our pages the day the discovery or the device is announced (not always easy, given our day jobs and night calls).

We are also proud of being a news source for the latest in the world of arts as it relates to medicine.

And so, on this note, here is our list of noteworthy stories from Medgadget, in no particular order:

1. Medgadget goes to Frost and Sullivan Medical Device Awards, and covers all the devices and technologies that were recognized by the "Oscars" of the biomed world. Rumor has it, that Medgadget is to go next year for the same ceremony. Details soon.

2. We learn that the overpaid leadership of the American Medical Association, bent on "branding" the organization to increase its membership, quietly decides to make American Medical News (AMNews)--"The Newspaper for America's Physicians"--a pay per view internet site. Medgadget starts a campaign to pressure the AMA to drop its plans. The grass root action reverberates through the entire medical blogosphere. Benjamin Mindell, editor of the American Medical News responds. And the result? The important public policy journal is still hidden from the public itself (unfortunately still number one search result on Google for "medical news"!). Additionally, the AMNews does not generate any "buzz" within the blogosphere, something that it should have been, as there are plenty of blogs out there interested in public policy issues. The AMA membership likely has not increased. And pundits responsible for the debacle are still at the helm of the AMA.

3. Medgadget nicely illustrates a previously undescribed surgical technique: the Chopstick Surgical Closure Technique. Although most of our surgical coverage this year was given over to robots.

4. 64-slice CT scanners go main stream as diagnostic modalities. Even Oprah finds them fascinating and useful, and in the process sends us more than 4,000 visits on the day of the show, all looking for 64-slice scanners (the hardest part was to investigate where the traffic was coming from). The coronary artery disease can now be visualized "in a heart beat." Medgadget covers Brilliance 64-slice CT Scanner by Philips, Aquilion 64 by Toshiba; Biograph 64 PET/CT by Siemens; GE's LightSpeed VCT, all of them well before the mainstream media.

5. The future of medical monitoring and treatment is wireless! Our faves: the WEALTHY wearable health system, and NASA's CPOD, and an untangled EKG (no "ICU spaghetti" system).

6. Medgadget's The Good Old Days archive grows to more than sixty stories. There is always something to learn from history, especially if you share our preoccupation with drugs, alcohol, celebrities, and sexually transmitted diseases.

7. We are the first news outlet to report on the new AMA logo to the public (and put it in historical context).

8. The intersection of medicine and sports brought some new devices in 2005, and we were excited to learn about performance-enhancing contact lenses, heatstroke-monitoring sunglasses, and other nifty developments.

9. It was a great year for Art and Medicine. Edwin Smith Papyrus was displayed at the Met; medical kitsch was shown in the Philadelphia Museum of Art; Alexander Tsiaras was shown at The National Museum of Health and Medicine in Washington, D.C. And, yes, we are obsessed with Alexander Tsiaras' art: this year's winners of the Medical Weblog Awards will get a copy of his book: The Architecture and Design of Man and Woman : The Marvel of the Human Body, Revealed.

10. Sex and dirty toys were used to generate cheap traffic, of course. Selling sex, unfortunately, did not work for us. But here's the list of attempts, nonetheless: the unforgettable Rape Trap and STD urinal, the Viagra Condom, and HarmonySystem for Sex Without (Physical) Pain, for paralyzed perverts, of course.

Did we forget something else? Of course, we did. So if you are new here, look through our archives.

What about the future? In the immediate future the task is a serious one: the voting for 2005 Medical Weblog Awards is in mere five days. We better buy some additional bandwidth!

Otherwise, we're looking forward to another healthy, prosperous year bringing you news of medical devices and breakthroughs. Be in touch, send us your email: we love to hear from you.

Thanks for everything!

All of us here at Medgadget.com wish you Merry Christmas, Happy Hanukkah or whatever it is that you celebrate that makes you happy! Please enjoy this wonderful but slightly schizophrenic time with your family and friends.

On Tuesday we will resume posting with our first ever year-end round up of the most interesting medgadgets, discoveries and stories of 2005.

Happy Holidays, everyone!

The MIT Technology Review has a report on a new use for functional MRI: Imaging the Unconscious. One hundred years later, some of Freud's notions are finally testable:

One of Freud's theories held that after a traumatic event, people might unconsciously associate a normally benign stimulus, say, a friendly golden retriever, with a previously fearful event, such as getting bitten by a Rottweiler. This theory seems to be true in the case of post-traumatic stress disorder (PTSD). Harmless sights and sounds, for instance, such as a bus traveling on down a street, can trigger a panic attack in someone with PTSD who was once involved in a bus crash. Furthermore, the sufferer may not be immediately able to pinpoint the cause of his or her anxiety attack.

Now scientists are using brain imaging techniques to explore how the unconscious fear signal may be turned up in people with PTSD and other anxiety disorders. To study the brain processes underlying anxiety, researchers use functional magnetic resonance imaging (fMRI) to measure a person's brain activity while he or she looks at threatening signals, such as a picture of a fearful face. These frightening pictures will spark activity in the part of the brain known as the amygdala, which is part of the evolutionarily ancient brain involved in processing emotion and fear. To study the unconscious aspects of fear and anxiety, the researchers flash the ominous picture so quickly that subjects don't consciously notice it -- the brain reacts to the image, even though the person cannot determine whether or not they actually saw it.

More from Prof Armony at McGill...

Yale scientists write, in the latest journal Chemistry and Biology, that emerging research on bacterial riboswitches offers new targets for the development of effective therapies against bacterial infection. Riboswitches are recently discovered RNA elements that control gene expression. Curious? See this press release. More about riboswitches.

The abstract...

Ever wonder why ice cream does not taste sweet when it is frozen, but only when it melts in the mouth? In addition, melted ice cream becomes supersweet, giving that special "ice cream kick". And what about that warm beer taste? Scientists from Belgium's Katholieke Universiteit Leuven have an explanation:

Physiologists from the university of Leuven have discovered that this Trpm5-channel in our taste buds is highly sensitive to changes in temperature. At 15°C the channel scarcely opens, whereas at 37°C its sensitivity is more than 100 times higher. The warmer the food or fluid in your mouth, that much stronger will TRPM5 react, and thus that much stronger is the electrical signal sent to the brain. For example, the sweet taste of ice cream will only be perceived when it melts and heats up in the mouth. If you serve the same ice cream warm, then the reaction of TRPM5 in your taste buds is much more intense and the taste of the melted ice cream is much sweeter.

Based on these findings, K.U.Leuven's researchers now conclude in Nature that TRPM5 lies at the basis of our taste's sensitivity to temperature. This was also confirmed in experiments on mice: taste responses increased dramatically when the temperature of sweet drinks was increased from 15°C to 37°C. This temperature sensitivity of sweet taste was entirely lacking in genetically altered mice that no longer produced the Trpm5 channel.

This research opens the way to the development of chemical substances influencing the functioning of the Trpm5-channels so as to suppress unpleasant tastes, for example, or to explore completely unprecedented and new taste experiences.

The press release...

The abstract at Nature...

Armor plating on Humvees would seem to have no drawbacks, but in fact, overheating becomes an issue for the soldiers riding inside. In the Iraqi sun, Humvee interior temperatures can apparently rise to 130 degrees. In response, the US Army is testing cooling vests for those stationed in Iraq:

...The vests are worn under body armor and a hose from each vest is plugged into the Humvee's on-board air-conditioning system. Liquid from the vehicle's AC system circulates through the vest, cooling its wearer...

...Each Humvee cooling kit consists of four water-filled vests known as Air Warrior Microclimatic Cooling Garments or MCGs. Fungicide-treated water is chilled by the AC system in the Humvee and circulated through the garment

A rapid-release system allows Soldiers to quickly disconnect the hoses so they can jump out of the vehicle and keep the vests on.

Via Engadget...