August 2006 Archive

Thursday, August 31, 2006

Radilex™: Rx for Ionizing Radiation

Filed under: Nuclear Medicine , Public Health

ImmuneRegen BioSciences, a company out of Scottsdale, Arizona, has inititated a new study at the Oak Ridge National Laboratory (ORNL) to further evaluate its drug Radilex™, to support its submission to the FDA in the future. The drug is thought to be a possible treatment of the effects of acute radiation exposure. Radilex™ is an analog of Substance P (Sar9, Met (O2)11-Substance P), widely distributed throughout the body neuropeptide.

Read more about this interesting and promising product and its history on the company's product page...

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Thursday, August 31, 2006

Bite Down on the Gnathograph

Filed under: the good old days...

Boing Boing points us to an amazing website of past technology, called Modern Mechanix ("Yesterday's tomorrow, today!") and a scary dental device (isn't that redundant?) known as the gnathograph:

WITH the aid of the "gnathograph," an instrument as mouth-filling as its name, a dentist's patients may now be assured of a perfect fit for artificial teeth. Fitted to the jaws as shown above, the new device registers the arrangement of the teeth and the direction of the "bite," to guide the dentist in straightening teeth or fitting inlays, crowns, bridges, and plates. Its inventor, Dr. Beverly B. McCollum of Los Angeles, Calif., demonstrates in the picture at the right how the instrument is then mounted for use in tooling a plate to just the right shape to give the most comfortable fit in the mouth.

We're not tooth experts, but we think dentists today accomplish similar measurements with soft alginate molds. Alginate, of course, is also used in cake frosting. This, dear readers, is progress...

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The Intraject® System

Filed under: Medicine , Neurology

According to Red Herring, Zogenix, Inc., a privately held pharmaceutical company, raised $60 million to help it bring to market the Intraject® system. This needle-free, single use, pre-filled and disposable subcutaneous delivery system of sumatriptan should make the treatment of migraines easier for patients.

Check out the product page here...

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New Device to Improve Vision for Patients with Tunnel Vision

Filed under: Ophthalmology

Researchers led by Dr Eli Peli at the Schepens Eye Research Institute, (a Harvard Medical School affiliate) have produced a vision aid system that superimposes parts of their outer field of view onto the center of their vision. More from the press release...

Peli's new visual aid - which he developed with the help of MicroOptical Corp. of Westwood, MA- allows the patients to see detailed visual information through the transparent display, while also viewing a superimposed minified outline version of a wider visual field. The tiny computer-video system provides updated outline information 30 times per second. When a patient becomes aware of a possible obstacle or important object in the superimposed outline image, he can move his head and eyes to look directly at the object through the display.
The purpose of the current study was to evaluate how effective the device would be in helping people with tunnel vision when searching for objects. Twelve patients with tunnel vision were asked to find targets that were projected outside their residual visual fields. The researchers found that the search directness was greatly improved for all patients when the device was used. They also found a significant reduction in search time (22%) in patients with a visual field wider than 10 [degrees].

Peli and his team believe that the performances of patients could be improved further -with additional training - even for those with smaller visual fields. "All patients only had an hour of training on this device before they were tested," says Luo "The search directness was improved for all subjects, which means they were not searching aimlessly, as they did without the device. However, the speed of head and eye movements was reduced when patients used the yet unfamiliar device. We believe that a few days of training would improve their speed and thus increase their search abilities dramatically."

Based on these results, and following further improvement of the device, the team will test the usefulness of the device by providing it to patients for use in their homes and for outdoor activities.

The press release is even so kind as to link directly to the abstract for the article it's covering in Investigative Ophthalmology and Visual Science. For examples on how to poorly cover science, see our previous work (...that is, on pointing out bad coverage, not executing it).

Also: MicroOptical Corp, who worked on the more gadgety side of things.

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Wednesday, August 30, 2006

Characterizing Nanocantilevers

Filed under: Nanomedicine

Scientists at Purdue University have discovered some pretty interesting properties of silicon nanocantilevers, miniature sensors that one day might become the engines for future medical diagnostic devices:

The nanocantilevers, which resemble tiny diving boards made of silicon, could be used in future detectors because they vibrate at different frequencies when contaminants stick to them, revealing the presence of dangerous substances. Because of the nanocantilever's minute size, it is more sensitive than larger devices, promising the development of advanced sensors that detect minute quantities of a contaminant to provide an early warning that a dangerous pathogen is present.
The researchers were surprised to learn that the cantilevers, coated with antibodies to detect certain viruses, attract different densities -- or quantity of antibodies per area -- depending on the size of the cantilever. The devices are immersed into a liquid containing the antibodies to allow the proteins to stick to the cantilever surface.

"But instead of simply attracting more antibodies because they are longer, the longer cantilevers also contained a greater density of antibodies, which was very unexpected," said Rashid Bashir, a researcher at the Birck Nanotechnology Center and a professor of electrical and computer engineering and biomedical engineering at Purdue University. The research also shows that the density is greater toward the free end of the cantilevers.

The engineers found that the cantilevers vibrate faster after the antibody attachment if the devices have about the same nanometer-range thickness as the protein layer. Moreover, the longer the protein-coated nanocantilever, the faster the vibration, which could only be explained if the density of antibodies were to increase with increasing lengths, Bashir said. The research group also proved this hypothesis using optical measurements and then worked with Ashraf Alam, a researcher at the Birck Nanotechnology Center and professor of electrical and computer engineering, to develop a mathematical model that describes the behavior...

The work, funded by the National Institutes of Health, is aimed at developing advanced sensors capable of detecting minute quantities of viruses, bacteria and other contaminants in air and fluids by coating the cantilevers with proteins, including antibodies that attract the contaminants. Such sensors will have applications in areas including environmental-health monitoring in hospitals and homeland security. So-called "lab-on-a-chip" technologies could make it possible to replace bulky lab equipment with miniature sensors, saving time, energy and materials. Thousands of the cantilevers can be fabricated on a 1-square-centimeter chip, Bashir said.

Link...

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Xbox for Stroke Rehabilitation

Filed under: Neurology , Rehab

Engineers at Rutgers hacked an Xbox and its Essential Reality P5 glove controller and developed a system to assist patients status post stroke with hand rehab:

The Rutgers hand rehabilitation system is an example of virtual rehabilitation, which combines virtual reality - computer-generated interactive visual environments in which users control actions in a lifelike way - with traditional therapy techniques. Virtual rehabilitation gives therapists new tools to do their jobs more effectively and engages patients who may otherwise lack interest or motivation to complete normal exercise regimens...
Rutgers' low-cost hand rehabilitation system is based on the commercially available Microsoft Xbox video game and Essential Reality P5 gaming glove that detects finger and wrist motions to manipulate on-screen images. The engineers made minor modifications to the equipment and created software that delivers two types of finger flexing exercises needed to help recover hand functions in stroke patients.

In one exercise, a patient attempts to wipe clean four vertical bars of "dirty" pixels that obscure a pleasant image on a computer display. The bars are erased in proportion to each finger's flexing motion, giving the patient immediate feedback on his or her performance. And in an exercise to promote finger flexing speed, a patient tries to make a fist quickly enough to "scare away" a butterfly flitting around on the screen.

The engineers noted that the gaming glove they use doesn't have the accuracy and resolution of gloves designed specifically for rehabilitation, nor can it measure exact joint movement or provide force feedback. But such systems may be attractive for clinics that can't afford more expensive equipment and could open the door for supplemental home training with remote monitoring by a clinician over an Internet connection.

Link...

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US Marshals Seize Defective Infusion Pumps at Alaris Facility

Filed under: Regulation

On August 25, US Marshals seized a batch of defective infusion pumps in a Cardinal Health Care (the pump's manufacturer) facility. Apparently, Alaris (part of Cardinal) had failed to follow FDA regulations in the wake of two warning letters issued back in 98 and 99, and continued to manufacture the pumps without fixing the flaw. According to the FDA...

The seized infusion pumps have a design defect called "key bounce" that may cause potential over-infusion of medications. This seizure was intended to ensure that infusion pumps located at Alaris' manufacturing facility are not distributed unless the problem is corrected.
Key bounce occurs when a number pressed on the pump registers twice although the operator only pressed the key once.

The infusion pumps were seized by the U.S. Marshals Service at Alaris' manufacturing facility in San Diego, California. The seized devices valued at more than an estimated 1.8 million dollars. Alaris has distributed these products nationally and internationally. No products were seized from healthcare facilities or individual users, and there are no plans to do so.

That last bit shows that the FDA was really looking to drive the point home to Alaris that they need to follow the rules. If this were really a major crisis, they would have seen to it that devices in the field were retired as well. There's a list of recommendations to users of the devices that basically says to be careful and double check what you entered. (We'd recommend to dial back the caffeine as well - the shakes can't help with this).

Of course Cardinal/Alaris has no mention of US Marshals in their press release, but they make sure to keep from spooking the investors:

There have been approximately 140,000 Alaris SE infusion pumps distributed worldwide during the past 12 years and the product line currently represents less than 1 percent of annual revenue for Cardinal Health's Clinical Technologies and Services segment.

Please Compost Your Corpses Properly

Filed under: etc.

Nobody likes dying. And now environmentalists are even making us feel bad about it!

As a body goes underground, we see a loved one being laid to rest. There are others, however, who see loads of toxic formaldehyde going into our beloved earth. Cremation apparently is not very eco-friendly either. So our concerned Swedish friends at Promessa have developed a method that is safe for the environment, but leaves your powdered corpse with little dignity. From their website:

The method behind ecological burial is crystal-clear, easy to grasp and accept. It is based on a new combination of tried-and-tested techniques that prepare the corpse for a natural process of decomposition. The procedure is justifiable in terms of ethical, moral, environmental and technical considerations, and does not subject the body to violent or destructive handling.
An important part of the solution is to remove that which is least important; the water that makes up 70 percent of a normal-sized body. Technically speaking, this is done using an entirely closed individual process in which the corpse is freeze-dried in liquid nitrogen.

Within a week and a half after death, the corpse is frozen to minus 18 degrees Celsius and then submerged in liquid nitrogen. This makes the body very brittle, and vibration of a specific amplitude transforms it into an organic powder that is then introduced into a vacuum chamber where the water is evaporated away.

The now dry powder then passes through a metal separator where any surgical spare parts and mercury are removed. In a similar way, the powder can be disinfected if required. The remains are now ready to be laid in a coffin made of corn starch. There is no hurry with the burial itself. The organic powder, which is hygienic and odorless, does not decompose when kept dry. The burial takes place in a shallow grave in living soil that turns the coffin and its contents into compost in about 6-12 months time. In conjunction with the burial and in accordance with the wishes of the deceased or next of kin, a bush or tree can be planted above the coffin. The compost formed can then be taken up by the plant, which can instill greater insight in and respect for the ecological cycle, of which every living thing is a part.

It appears a lot of thought has gone into this process, and it does appear to have some environmental value... But being freeze-dried, vibrated until I turn into a powder, and then filtered for toxic metals does not sound like I'm not subject to any "violent and destructive handling." Furthermore, if water is 70% of your body, isn't it the most important part? Without it one would resemble beef jerky more than a person. Finally, I'm a little confused about the corn starch coffin. Is something wrong with the styrofoam coffin I was planning on using?

Custom-Built Body Parts: Little Shop of Horrors?

Filed under: Orthopedic Surgery

We recently learned of a Michigan startup company that makes display models and test pieces for medical device firms. Why should we bring this to your attention? Because the pieces are apparently very accurate stand-ins for human flesh and bone. The company is Medical Engineering and Design, based in Michigan, founded last year by Robin Williams (no, not the actor) and Michael Zeeff:

An upper torso that includes the upper back, shoulders, neck and head produced in urethane by her company costs between $400 and $700. Real human cadavers start at about $5,000, according to Annie Cheney, author of "Body Brokers: Inside America's Underground Trade in Human Remains."

Aside from the cost, Williams said, rules and regulations about the use of cadavers have become much more stringent...

...Zeeff said employees are taught anatomy "one bone at a time." He said he has faced a steep learning curve as he's tried to master all of the 400 different bones in the body.

"A full spine will take about six hours to make and contains about 26 individual pieces," Zeeff said. "As I get to know each step, I'm learning to make a model to make a part."

Williams said the company carries no inventory because its sales are custom orders - for a replica of a human head with a tumor inside, for example, or a spinal column with a deformity that simulates a real malady. Medical-products makers use such items to show how their products can be applied.

The company is apparently too small to have a website, or pictures, which is really a shame. We're very curious as to how their human models have nearly twice as many bones as, say, real humans. Still, we bet orders would start pouring in, if people could see their wares online.

The company won't fill orders that Williams and Zeeff consider morally or ethically inappropriate.

Damn. We suppose "pranks at the nursing station" may fall under that category...

Update: The firm does indeed have a website, and a beautiful one it is, with multiple photos...

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On Alert in The Melatonin Room

Filed under: Neurology

are you paying attention? The far-out art/science/tech site We-Make-Money-Not-Art has impressed us again with their ability to unearth cool projects based on human physiology. This post covers an art exhibit called the Melatonin Room, by Swiss architects Jean-Gilles Decosterd and Philippe Rahm:

The melatonin regulates levels of alertness in the human body. A high level induces sleepiness, a low level greater alertness. Two climates alternate in the Melatonin Room. The first is defined by the emission of a bright green electromagnetic radiation at 509 nm, at an intensity of 2000 lux, which eliminates the production of melatonin, the space becomes thus a physically motivating place. The second climate is a dissemination of ultraviolet rays, bathing the visitor in soft blue light which stimulate the production of melatonin. This "physiological architecture" explores the ways environments can change consciousness.

Why do so many of these exhibits appear in Europe? We suppose it's because they make more art, and less money. Anyway, this is one case of artists getting a little ahead of the science -- we know that light can change pineal secretion of melatonin, sure, but that's a long way off from saying certain light frequencies make you more alert. All doctors can really trust is that melatonin is effective for jet-lag.

At Medgadget, the best bet for alertness-on-demand remains Dunkin' Donuts coffee -- though we suppose sipping it in a green melatonin room would be stimulating, as well.

More hormone-activating architecture from WMMNA...

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Convalescent Plasma: Future H5N1 Treatment?

Filed under: Public Health , the good old days...

Since we are all sitting here and waiting and waiting for bird flu to hit, we have some extra time to look at what has happened during the Spanish flu between 1918-1920. Military docs from the Bureau of Medicine and Surgery, U.S. Navy and Uniformed Services University of the Health Sciences have published a meta-analysis study of research published in those dark days of the early 20th century. Their paper, in the latest Annals of Internal Medicine, shows that using influenza-convalescent human blood products (i.e. human plasma containing H5N1 antibodies from survivors) might possibly save lives. From an accompanying editorial:

In a thorough review and analysis of the historical literature, Luke and colleagues document the effects of passive immunotherapy. They found 8 studies that evaluated the effects of therapy with serum or plasma from convalescent patients on the course of clinically diagnosed influenza pneumonia during the 1918 Spanish influenza pandemic. Although the quality of these studies was relatively poor by modern standards, they all reached similar conclusions. In 6 of these studies, treatment was compared with a control group that received standard care, and in each of these reports, the mortality rate was lower in treated patients, although the decrease was statistically significant in only 3 reports. Two of the studies also compared the outcomes in those who received early treatment and those who received late treatment. An additional 2 reports compared early and late therapy but did not have an untreated control group. These studies demonstrated that only those who received early intervention experienced a beneficial effect of serum therapy, which is consistent with reports of serotherapy for other human infectious diseases. Luke and colleagues discarded multiple other reports that did not meet the methodologic criteria for inclusion in their meta-analysis. These weaker studies also supported the hypothesis that passive serotherapy was useful in treating Spanish influenza.
Would a similar approach be effective and feasible in the event of a pandemic of H5N1 influenza? Passive immunotherapy to treat infection with influenza viruses, including H5N1, has been effective in a mouse model. Other viral diseases offer ample precedent: Passive antibody prevents many human viral diseases, including varicella, rabies, hepatitis A and B, and respiratory syncytial virus (RSV). However, the distinction between prevention of disease and treatment of active disease is important. Few recent data support the use of passive antibody therapeutically after disease manifestations have already begun. For example, although passive antibody is highly effective at prevention of RSV infection in high-risk infants, systemic administration of antibody with high levels of RSV neutralizing activity is not useful therapeutically in infants with RSV disease.

Nevertheless, the concept is important and it should be explored further...

The press release...

The paper at the Annals of Internal Medicine...

The editorial...

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It's All in the (Microbial) Family

Filed under: in the news...

Researchers from Rice have conclusively shown that even single-celled species are capable of recognizing their own family members, particularly in times of need:

The new study is based on an examination of single-celled Dictyostelium purpureum, a common soil microbe that feeds on bacteria. In the wild, when food runs short, D. purpureum aggregate together by the thousands, forming first into long narrow slugs and then into hair-like fruiting bodies. Resembling miniature mushrooms, these fruiting bodies consist of both a freestanding stalk and the spores that sit atop it. Ultimately, the spores are carried away, usually on the legs of passing creatures, to start the life cycle all over again. But in order to disperse the spores, some of the colony's individuals must altruistically sacrifice themselves in order to make the stalk.
Mehdiabadi and others in the lab of Rice evolutionary biologists Joan Strassmann and David Queller sought to find out whether D. purpureum discriminate by preferentially directing this altruism toward their relatives.

The team collected wild strains of D. purpureum from the Houston Arboretum and took them back to the lab where they were cultured in dishes. In each of 14 experiments, a pair of strains were placed in a dish in equal proportion, and one of the strains in each pair was labeled with a fluorescent dye.

Food was withheld, causing the microbes in each dish to form dozens of slugs and fruiting bodies. Upon observing their social development, the team found that individual fruiting bodies contained predominantly one strain or the other.

"Our experiments ruled out potential differences in developmental timing and showed that these organisms preferentially associate with their own kin," said Strassmann, the Harry C. and Olga K. Wiess Professor in Natural Sciences, who also chairs Rice's Department of Ecology and Evolutionary Biology.

It's unclear how D. purpureum distinguishes relatives from non-relatives, but Mehdiabadi said the process likely relies on a genetic mechanism.

Link...

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Tuesday, August 29, 2006

Nanoparticles and siRNA: A Perfect Marriage?

Filed under: Genetics , Nanomedicine

Next month's in-depth feature story over at the National Cancer Institute's Alliance for Nanotechnology in Cancer is about the opportunities that nanotechnology can offer in RNA silencing, a recently discovered mechanism that regulates translation of genetic material into protein. RNA silencing via nanodelivered double-stranded small interfering RNA (siRNA) molecules can offer a number of possibilities in treating cancer, autoimmune disorders and other diseases. As usual, the monthly feature story is not technical and is an easy and interesting read. Link...

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CDC: FluChip Performs Well

Filed under: Medicine , Public Health

CU-Boulder Professors Robert Kuchta and Kathy Rowlen display a scanner and the Flu Chip

FluChip, a microchip device developed by scientists from the University of Colorado at Boulder, and reported by us last year, has shown itself quite reliable in characterizing influenza's subtypes, according to research from the Centers for Disease Control and Prevention (CDC). Hence the headline: Quick Diagnosis of Flu Strains Possible with New Microchip Test

The FluChip is a type of microarray, commonly called a gene chip. Although there are numerous variations, microarrays can be made by using a robotic arm to drop hundreds or thousands of spots of genetic material--DNA or RNA--of known sequence onto a microscope slide. The spots, called probes, are then exposed to a sample of unknown composition: for instance, material taken from a person with an undiagnosed illness. Probes that match gene sequences of bacteria or viruses present in the sample result in capture of the target gene. By analyzing the pattern of captured targets, doctors can diagnose the cause of infection.
A key challenge in designing a gene chip for flu diagnosis is determining which flu virus gene sequences to use as probes, notes Dr. Rowlen. In a companion paper, the researchers describe a powerful new way to scan vast amounts of flu virus genetic information to find the most informative sequences. "Our goal was to develop an efficient method for mining large databases to identify regions of the flu genome that are largely the same from strain to strain as well as strain-specific sequences," Dr. Rowlen says.

Beginning with a pool of nearly 5,000 flu gene sequences, the investigators used the data mining process to select 55 flu RNA sequences for use as probes on the FluChip. Among them were probes chosen to enable detection of two of the most common flu strains currently circulating in humans, the H1N1 and H3N2 strains, as well as the avian flu strain H5N1.

The CDC provided flu isolates to the University of Colorado researchers to identify using the FluChip. The samples included flu strains that infect humans, horses, birds and swine. CDC shared its technical expertise on influenza and worked alongside University of Colorado staff in CDC laboratories to process the influenza samples, test the FluChip technology and analyze the results. Combined results after two rounds of tests showed that the FluChip allowed users to obtain correct information about both type and subtype--considered a full characterization of a strain--from 72 percent of the samples. Full information on type--but only partial information on subtype--was obtained for 13 percent of the samples, while 10 percent of the samples could be identified by type only (no information about subtype). It took about 11 hours to conduct the tests and learn the identities of the strains, report the scientists.

"New" test for flu news wire...

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In the Works: Proton Treatment from MIT

Filed under: Nuclear Medicine , Oncology , Radiology

MIT and Still River Systems Inc., a Littleton, Mass. company are working on developing proton treatment for radiation oncology:

The beauty of protons is that they are quite energetic, but their energy can be controlled so they do less collateral damage to normal tissues, compared to powerful x-ray beams. Protons enter the body through skin and tissue, hit the tumor and stop there, minimizing other damage.
Protons are far more massive than the photons in x-rays, and the x-rays tend to pass directly through tissues and can harm living cells along the entire path. The side effects often include skin burns and other forms of tissue damage.

The new machines, in fact, should allow radiation specialists to deposit a far bigger dose of killing power inside the tumor, but spare more of the surrounding normal tissues. This is expected to increase tumor control rates while minimizing side effects.

Because of their high energy and controllability, protons have been used as anti-cancer bullets in the past, with promising results. But medical centers can't easily come up with the $100 million or more needed to build a proton machine dedicated to this medical use. That's because protons are produced inside the huge, expensive atomic accelerators that are usually employed at major atomic research centers, including national laboratories.

Now, Antaya [Timothy Antaya is a physicist at MIT's Plasma Science and Fusion Center --ed.] and his colleagues at MIT and at Still River Systems Inc. think they can provide the new machine for far less money, have it occupy just one moderate-size hospital treatment room, and achieve better results than x-ray therapy. MIT is licensing the technology to Still River Systems.

Industry is already showing acute interest in the new technology because more than half of all cancer patients are now treated with radiation, meaning there are two million radiation patients worldwide. That offers a huge market for an effective new radiation system, and the directors of major cancer research and treatment centers are already enthusiastic, Antaya said.

More...

Still River Systems' empty website...

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Nanowires to Stimulate Nerve Signals

Filed under: Neurology

Researchers at Harvard University have opened a new link between neuroscience and nanotechnology in using slender silicon nanowires to stimulate, detect, and inhibit nerve signals along the axons and dendrites of live mammalian neurons:

Harvard chemist Charles M. Lieber and colleagues report on this marriage of nanowires and neurons this week in the journal Science.
"We describe the first artificial synapses between nanoelectronic devices and individual mammalian neurons, and also the first linking of a solid-state device -- a nanowire transistor -- to the neuronal projections that interconnect and carry information in the brain," says Lieber, the Mark Hyman Jr. Professor of Chemistry in Harvard's Faculty of Arts and Sciences and Division of Engineering and Applied Sciences. "These extremely local devices can detect, stimulate, and inhibit propagation of neuronal signals with a spatial resolution unmatched by existing techniques."

Electrophysiological measurements of brain activity play an important role in understanding signal propagation through individual neurons and neuronal networks, but existing technologies are relatively crude: Micropipette electrodes poked into cells are invasive and harmful, and microfabricated electrode arrays are too bulky to detect activity at the level of individual axons and dendrites, the neuronal projections responsible for electrical signal propagation and interneuron communication.

By contrast, the tiny nanowire transistors developed by Lieber and colleagues gently touch a neuronal projection to form a hybrid synapse, making them noninvasive, and are thousands of times smaller than the electronics now used to measure brain activity.

"Study" Says FDA Advisors Typically Recommend Approval, Medgadget.com Disapproves of AP's Choices in Science Coverage

Filed under: in the news...

So, without further adieu, we'll give you the flavor of the study they're talking about...

A new study finds that F-D-A advisers rarely say 'no' when deciding whether to recommend a drug or medical device for approval.
The study's author says that raises question about the independence of committees the Food and Drug Administration counts on for safety feedback. And author Diana Zucker -- of the National Research Center for Women and Families -- says the panels "seem more like a rubber stamp."

The report looked at the voting patterns of six randomly selected F-D-A drug advisory committees and five medical device advisory panels from 1998 through 2005. Medical advisory panels recommended approval 76 percent of the time and medical device panels 82 percent of the time.

What's so bad about this? First of all, it takes up the first 4 pages of results in a Google news search for medical device news. Second, it appears that the "study" in question was not published in any peer-reviewed literature, either medical or otherwise. That said, an attempt to find Diane Zucker, author of "the study" (which is all the AP feels the need to identify it by) at the National Research Center for Women and Families website yields no results. So, until someone can point us to the study in question, the title stands as true.

What we really suspect is that of course the FDA (without the silly AP dashes), is going to tend towards approval for medical devices. Devices are usually approved after a lengthy process involving round and round of discussion between an FDA liason and the device's manufacturer. In addition there's really no reason that the majority of devices shouldn't be recommended for approval. That's like saying the majority of high school students graduate, therefore high schools are mostly a rubber stamp institution.

We were hoping to see how the study in question came up with these numbers, but alas...it apparently doesn't exist. Press releases do not equal research...

The Dawn of Bioengineering in Treating Irregular Heartbeats

Filed under: Cardiology

Researchers at the University of California-Davis have successfully restored normal heart rhythms in pigs with electronic pacemakers using a custom designed protein and gene delivery system:

The UC Davis study, which was co-authored by an international team that included scientists from the University of Hong Kong and Johns Hopkins University, is published in the current issue of the journal Circulation...
In the current study, the researchers delivered a gene encoding a bioengineered cell-surface protein to heart muscle cells of pigs. This protein mimics the combined action of several proteins called HCN ion channels, which play a critical role in maintaining a normal, evenly paced heartbeat. These channels control the flow of sodium and potassium ions in and out of cells that regulate the electrical impulses of the heart.

"These channels are critical to normal heart function. We were able to make one protein that codes for a single channel that does the work normally required by several," Li explained.

By getting heart muscle cells to produce bioengineered HCN channels, Li and his colleagues were able to reconstruct the SA node of the heart in pigs with implanted electronic pacemakers. The SA node is normally located on the right atrium, the upper right chamber of the heart that receives deoxygenated blood from the body.

"We were even able to create new pacemaker regions on the left atrium," Li said.

According to Li, the current study moves research beyond using animal models such as mice and rats, whose hearts can beat up to 600 times per minute. Large animals such as pigs make for far more realistic models because their anatomy and physiology, including average heart rates of about 70 to 80 beats per minute, are similar to humans.

In the current study, researchers used radiofrequency ablation to remove the SA nodes in pigs' hearts. This is the same minimally invasive technique cardiologists use in clinics to destroy the heart cells that cause abnormal electrical discharges and rapid heart rates in their patients. To restore the SA node function and evaluate the bioengineered cells, Li's team then implanted electronic cardiac pacemakers like those used in humans and injected an adenovirus carrying a gene encoding for the engineered HCN protein into the heart muscle. Adenovirus has the ability to deliver its own genes into a host cell and hijack its protein-synthesizing machinery. Scientists use this ability to deliver genes of interest into cells.

In a matter of days following the gene transfer, the pigs' hearts had generated bioartificial nodes at the injection sites. Li explained that, through gene expression, normal muscle cells of the heart were converted into pacemaker cells by a process called transdifferentiation. Studies done two weeks after the injections showed the new nodes were able to take over pacemaking function from the electronic devices. The results also have implications for future stem cell research.

Link...

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Researchers Study Flamingos for Balance Lessons

Filed under: etc.

Researchers Lena Ting and Young-Hui Chang of Emory and Georgia Tech Universities are studying the biomechanics of flamingos in an effort to see what makes them so good at standing on one leg all day. While reasoning behind this monopodistic silliness remains an unanswered scientific question, they hope to apply the results to better prosthetics or physical therapy...

Although no one seems to know for certain why flamingos do it, the scientists hope that by learning how, they will be able to help humans.
Lena Ting is a posture expert at the Wallace H. Coulter Department of Biomedical Engineering, a joint department of the two universities. Young-Hui Chang is a locomotion expert in Tech's school of applied physiology.

On Friday, they took their high-tech tools to Zoo Atlanta for the first time to examine how a flamingo's body shifts as it rests on one foot.

"The flamingo's ability to balance on one leg for long periods represents the extreme in balance control," said Chang. "It's a good model to study."

The newest addition hatched Monday morning, weighing in at just over 2 ounces, as gray and soft as a dandelion ripe for wish-making. A few hours later, it stood briefly, then wobbled down to sit again. By week's end, it will be standing on one foot for short periods.

The scientists hope to measure the progress of the hatchlings from the early stages until they join the adult flock late this fall.

Odd that the animals adorning kooky old ladies' lawns might hold the key to better hip replacements for the very same...

More from the Atlanta Journal-Constitution (Photo credit: Joey Ivansco, AJC)...

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Thursday, August 31, 2006

Radilex™: Rx for Ionizing Radiation

Thursday, August 31, 2006

Bite Down on the Gnathograph

The Intraject® System

New Device to Improve Vision for Patients with Tunnel Vision

Wednesday, August 30, 2006

Characterizing Nanocantilevers

Xbox for Stroke Rehabilitation

US Marshals Seize Defective Infusion Pumps at Alaris Facility

Please Compost Your Corpses Properly

Custom-Built Body Parts: Little Shop of Horrors?

On Alert in The Melatonin Room

Convalescent Plasma: Future H5N1 Treatment?

It's All in the (Microbial) Family

Tuesday, August 29, 2006

Nanoparticles and siRNA: A Perfect Marriage?

CDC: FluChip Performs Well

In the Works: Proton Treatment from MIT

Nanowires to Stimulate Nerve Signals

"Study" Says FDA Advisors Typically Recommend Approval, Medgadget.com Disapproves of AP's Choices in Science Coverage

The Dawn of Bioengineering in Treating Irregular Heartbeats

Researchers Study Flamingos for Balance Lessons