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Electrophysiology: an interview with Dr Kaylene Young

Electrophysiology: an interview with Dr Kaylene Young

Please could you give a brief introduction to electrophysiology?

Bioelectricity is an essential part of our make-up. All cells in our body communicate by electrical activity. If an electrical charge is applied to one of our muscles it will interpret that electrical activity as a signal telling it to contract. When doctors send patients for an electrocardiogram test, they are measuring the electrical impulses emitted by cells with every heart beat.

Electrophysiology is a technique that uses specialist equipment to measure bioelectrical currents very precisely, allowing scientists to measure the electrical activity, not of an entire organ, but of a single cell, or even a small region of a cell.

What can electrophysiology teach us about cell function?

Each cell has an outer membrane, internal fluid and multiple organelles (cell’s equivalent of organs). While the cell is a contained system, its function is altered by the signals that it receives from other cells, in the form of bioelectricity.

Electrophysiology equipment allows researchers to measure bioelectricity at the individual cell level, in order to understand how cells communicate and respond to stimuli such as drugs or toxins. These measurements of a cell’s function are made in real-time, providing information about which components of the cell respond and how quickly they respond to a stimulus.

Can electrophysiology teach us about the cellular basis of diseases?

Yes, electrophysiology is one of the most suitable techniques for these types of studies. It allows researchers to determine precisely how a disease process is exerting its effect and having a consequence for cell function. This type of information is particularly beneficial when developing suitable therapeutic treatments.

Is electrophysiology also useful for testing drug treatments?

Absolutely! Therapeutic agents often function by activating or blocking channels, pores or transporters on the surface of cells. This effectively changes the electrical activity of the cell. Electrophysiology can be used to directly evaluate how effective a drug is at activating or blocking its target, and how specific the effect is on a variety of cell types.

You have recently been reported as saying that “electrophysiology is rapidly becoming an essential component of neuroscience research”. Why do you think this is the case?

There are multiple neuroscience research groups at UTAS who are eager to use the new electrophysiology equipment, in particular the neuroscience groups of the Menzies Research Institute managed by Dr Kaylene Young, Prof David Small, A/Prof Tracey Dickson and Dr Lisa Foa.

The brain contains billions of nerve cells, yet these cells do not work alone – they form a connected network. Healthy brain function relies on information being sorted and then faithfully transferred to the most appropriate brain region. This information transfer is seen by individual brain cells as an ion flux, which is an electric current.

Some diseases cause brain cells to receive too much or too little electric input from surrounding cells. Either situation can disrupt the cell’s function, and even result in its death and removal from the network. As neuroscientists we are trying to understand the disease process, and intervene to protect and even restore brain function. Therefore it is essential that we understand how brain cells are being electrically stimulated normally, and how this changes as part of a disease’s pathology.

Also, as we better develop cell replacement therapies, and start to implement them, it is going to be very important to ensure that the new replacement cells become correctly wired into the brain network. Electrophysiology allows us to measure all of these things.

Do you think electrophysiology will also become an important component in other research fields?

All of the cells in the body communicate via ion flux (electrical current) – only the size of the current is often larger in nerve cells. Once the equipment is fully operational in the Institute, it is envisaged that the list of users will expand to include other researchers within the Institute, such as the Muscle Diabetes Research Group led by Professor Steve Rattigan, Dr Steve Richards and Dr Michelle Keske.

The University of Tasmania’s Menzies Research Institute has recently been awarded a grant from the Ramaciotti Foundations. Please could you outline how you plan to use this grant?

In conjunction with the Ramaciotti Foundation, Menzies Research Institute Tasmania aims to establish a multi-user, state-of-the-art mammalian cell electrophysiology facility. This will be the first equipment of its kind in Tasmania, and the facility will be available for use by researchers within the University of Tasmania, as well as partner organisations including The Antarctic Division and CSIRO.

What impact do you think this research will have?

The new equipment will be used for various research projects that each aim to improve human health. Four of the Menzies Research Institute Tasmania neuroscience groups plan to use the equipment as soon as it is established in the building.

Dr Young’s laboratory focuses on promoting the generation of new cells within the adult brain, and she will use the equipment to examine the ability of the newly generated cells to electrically integrate into the pre-existing circuitry.

Prof. David Small’s research aims to understand Alzheimer’s Disease pathology and electrophysiology equipment will allow him to better assess how the pathology negatively affects brain cell function.

Research in Dr Foa’s laboratory aims to improve our understanding of the mechanisms that control calcium signalling (calcium ion flux), as this has direct implications for a wide variety of developmental conditions including mental retardation, autism and schizophrenia and also regeneration after injury.

A/Prof. Dickson investigates how the brain responds to trauma and disease, and has a particular interest in developing and testing novel therapeutics to determine how effective they are in preventing or slowing the progression of brain damage.

How do you think the future of research using electrophysiology will progress?

This equipment will allow us to examine aspects of cell function that would have previously gone un-noticed. Researchers are constantly finding new ways to use this technology and new applications for it in investigating what are very small cellular changes, but have very large consequences for how our bodies function.

Would you like to make any further comments?

We would like to thank the Ramaciotti Foundation for their generous support.

Where can readers find more information?

More information about the researchers at Menzies Research Institute Tasmania that will be using this equipment is available on the Institute website.

http://www.menzies.utas.edu.au/article.php?Doo=ContentView&id=698

About Dr Kaylene Young

Kaylene Young BIG IMAGEHONOURS

Dr Kaylene Young was the recipient of a Sir John Monash Science Scholarship, and graduated from Monash University with a Bachelor of Science (hons) degree in 2000.

PHD

As the recipient of an Australian Postgraduate Award, she was extremely fortunate to pursue her interest in adult brain stem cell biology, by undertaking graduate training in Prof Perry Bartlett’s laboratory, at the Walter and Eliza Hall Institute (University of Melbourne), where she was co-supervised by A/Prof Elizabeth Coulson.

She spent the final 18 months of her PhD assisting in the successful establishment of the Queensland Brain Institute, at the University of Queensland, where she trained new students and staff to purify brain stem cells and maintain them in culture.

POSTDOC

In 2004 she moved to the United Kingdom to work as a postdoctoral research fellow at University College London (UCL). Her early research in the UK revealed that there are multiple types of stem cells in the mature brain that generate a variety of different types of new nerve cells.

Following this work she was awarded an international Career Development Award in Stem Cell Research, which allowed her to remain at UCL and study a cell type called Oligodendrocyte Progenitor Cells (OPCs), which are the largest actively dividing cell population in the mature brain. She discovered that OPCs generate significant numbers of new insulating cells for the mature central nervous system, a discovery that is likely to be extremely important for future therapies aimed at treating multiple sclerosis (loss of insulating cells).

GROUP LEADER

In 2011 she was appointed as a research group leader at the Menzies Research Institute Tasmania within the Neurodegeneration Division. Having successfully applied for an international project grant, she spent the eighteen months of this position learning how to make electrical recordings from brain cells, receiving expert training in her collaborator, Prof David Attwell’s laboratory (also UCL).

The Ramaciotti Equipment Grant that was recently awarded to the Menzies Research Institute Tasmania will allow the institute to purchase the equipment that is required to make these recordings. At the Menzies Research Institute they conduct a significant amount of nervous system research. Nerve cells and many other cell types require well regulated electrical activity for their function. The new equipment will be set up as a core facility and Kaylene will be training many of the staff and students to use it. They will measure the electrical activity of cells, determine how this changes as disease symptoms progress, and determine how well potential drug treatments can restore normal electrical activity to those cells.

Kaylene was recently awarded an NHMRC career development award to allow her to build the capacity of her laboratory and pass on her newly acquired expertise to others in the Institute.

Source : http://www.news-medical.net/news/20121121/Electrophysiology-an-interview-with-Dr-Kaylene-Young.aspx

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Tiny Vital Signs Monitor Powered by Passing Radio Waves

Tiny Vital Signs Monitor Powered by Passing Radio Waves

Tiny Vital Signs Monitor Powered by Passing Radio Waves

CORVALLIS, Ore. – Electrical engineers at Oregon State University have developed new technology to monitor medical vital signs, with sophisticated sensors so small and cheap they could fit onto a bandage, be manufactured in high volumes and cost less than a quarter.

A patent is being processed for the monitoring system and it’s now ready for clinical trials, researchers say. When commercialized, it could be used as a disposable electronic sensor, with many potential applications due to its powerful performance, small size, and low cost.

Heart monitoring is one obvious candidate, since the system could gather data on some components of an EKG, such as pulse rate and atrial fibrillation. Its ability to measure EEG brain signals could find use in nursing care for patients with dementia, and recordings of physical activity could improve weight loss programs. Measurements of perspiration and temperature could provide data on infection or disease onset.

And of course, if you can measure pulse rate and skin responses, why not a lie detector?

“Current technology allows you to measure these body signals using bulky, power-consuming, costly instruments,” said Patrick Chiang, an associate professor in the OSU School of Electrical Engineering and Computer Science.

“What we’ve enabled is the integration of these large components onto a single microchip, achieving significant improvements in power consumption,” Chiang said. “We can now make important biomedical measurements more portable, routine, convenient and affordable than ever before.”

The much higher cost and larger size of conventional body data monitoring precludes many possible uses, Chiang said. Compared to other technologies, the new system-on-a-chip cuts the size, weight, power consumption and cost by about 10 times.

Some of the existing technologies that would compete with this system, such as pedometers currently in use to measure physical activity, cost $100 or more. The new electronics developed at OSU, by comparison, are about the size and thickness of a postage stamp, and could easily just be taped over the heart or at other body locations to measure vital signs.

Part of what enables this small size, Chiang said, is that the system doesn’t have a battery. It harvests the sparse radio-frequency energy from a nearby device – in this case, a cell phone. The small smart phone carried by hundreds of millions of people around the world can now provide the energy for important biomedical monitoring at the same time.

“The entire field of wearable body monitors is pretty exciting,” Chiang said. “By being able to dramatically reduce the size, weight and cost of these devices, it opens new possibilities in medical treatment, health care, disease prevention, weight management and other fields.”

The new technology could be used in conjunction with cell phones or other radio-frequency devices within about 15 feet, but the underlying micropowered system-on-a-chip technology can be run by other energy-harvested power sources, such as body heat or physical movement.

OSU will work to develop this technology in collaboration with private industry, an increasing area of emphasis for the university. In the past two years, private financing of OSU research has increased by 42 percent, and the university has signed 108 research-based licenses of OSU technology.

This research was recently reported at the Custom Integrated Circuits Conference in San Jose, Calif. It has been supported by the National Science Foundation and the Catalyst Foundation.

About the OSU College of Engineering: The OSU College of Engineering is among the nation’s largest and most productive engineering programs. In the past six years, the College has more than doubled its research expenditures to $27.5 million by emphasizing highly collaborative research that solves global problems, spins out new companies, and produces opportunity for students through hands-on learning.

At Oregon State University engineers have developed a postage stamp-sized microchip capable of performing ECG and EEG signal gathering using very little external power. The device doesn’t even have its own battery but instead harvests radio waves from nearby devices to generate its electric current. Moreover, the chip can be made to interface with other energy gathering devices that would provide it power sourced from the wearer’s body heat and muscle movement.

Its smalls size, minimal power requirements, and a significantly reduced cost of manufacturing compared to existing devices with similar capabilities should make the device useful for continuous health monitoring and offer an interesting new option for the Quantified Self crowd. Certainly activity trackers of the future will be significantly more useful when they can provide 24/7 monitoring of the user’s heart beats and maybe even mental state.

From Oregon State:

“Current technology allows you to measure these body signals using bulky, power-consuming, costly instruments,” said Patrick Chiang, an associate professor in the OSU School of Electrical Engineering and Computer Science.

“What we’ve enabled is the integration of these large components onto a single microchip, achieving significant improvements in power consumption,” Chiang said. “We can now make important biomedical measurements more portable, routine, convenient and affordable than ever before.”

The much higher cost and larger size of conventional body data monitoring precludes many possible uses, Chiang said. Compared to other technologies, the new system-on-a-chip cuts the size, weight, power consumption and cost by about 10 times.

Some of the existing technologies that would compete with this system, such as pedometers currently in use to measure physical activity, cost $100 or more. The new electronics developed at OSU, by comparison, are about the size and thickness of a postage stamp, and could easily just be taped over the heart or at other body locations to measure vital signs.

Source : http://oregonstate.edu/ua/ncs/archives/2012/nov/medical-vital-sign-monitoring-reduced-size-postage-stamp

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Novel electrotherapy reduces energy needed to re-establish normal rhythm in the heart

Novel electrotherapy reduces energy needed to re-establish normal rhythm in the heart

Implantable defibrillators currently on the market apply between 600 and 900 volts to the heart, almost 10 times the voltage from an electric outlet, says Ajit H. Janardhan, MD, PhD, a cardiac electrophysiology fellow at the Washington University’s School of Medicine.

After being shocked, he says, some patients get post-traumatic stress disorder. Patients may even go so far as to ask their physicians to remove the defibrillator, even though they understand that the device has saved their lives.

The huge shocks are not only unbearably painful, they damage the heart muscle and have been shown in many studies to be associated with increased mortality. In an advance online edition of the Journal of American College of Cardiology, Janardhan and Igor Efimov, PhD, professor of biomedical engineering in the School of Engineering & Applied Science, report on a low-energy defibrillation scheme that significantly reduces the energy needed to re-establish a normal rhythm in the heart’s main chambers.

They hope this electrotherapy will be much less painful than shocks from existing implantable defibrillators, and may even fall beneath the threshold at which patients begin to perceive pain.

The team has just received a National Institutes of Health grant to develop a prototype low-energy defibrillator for humans and plan to begin clinical trials of the device shortly.

Losing the beat

The lub-dub of the heartbeat begins with an electrical impulse generated by the sinoatrial node, a group of cells on the wall of the right atrium that is the heart’s natural pacemaker.

Spreading through conductive pathways in the heart, the electrical signal first causes the two upper chambers of the heart (the atria) to contract, and then, a split second later, the two lower chambers (the ventricles), coordinated motions that efficiently pump blood to the rest of the body.

The synchronized squeezing of a normal heartbeat is called sinus rhythm, after the node that triggers it.

The rhythm can go wrong in many different ways, but the real killer is ventricular tachycardia. Ventricular tachycardia is an abnormal heart rhythm that starts in the ventricles rather than from the sinoatrial node, and that causes the heart to beat at a rate too fast (tachy is Greek for rapid or fast) to efficiently pump blood to the rest of the body.

Moreover, the rapid heartbeat can degenerate precipitously into ventricular fibrillation, or the loss of all rhythm, says Efimov. During ventricular fibrillation the uncoordinated contraction of heart muscle prevents the heart from pumping blood at all, and without immediate intervention, death quickly follows.

Most people who develop ventricular tachycardia and ventricular fibrillation outside the hospital die, says Janardhan, but studies show that if we implant a defibrillator in patients with a weak heart that does not pump as strongly as it should, we can significantly reduce mortality.

Restarting the rhythm

There are really only three therapies for ventricular tachycardia, Efimov says. One is drugs that reduce the likelihood of tachycardia, but drugs are often ineffective.

The second is ablation, or the deliberate creation of nonconductive scar tissue within the heart that blocks abnormal conductive patterns and redirects electrical activity to more normal pathways.

The major problem with ablation, says Efimov, is recurrence. It’s a temporary measure, not a cure. Patients typically need additional treatment within five years.

The third therapy is an implantable cardioverter defibrillator, or ICD. These devices are placed beneath the skin in the chest and monitor the rate and rhythm of the heart. If they detect ventricular tachycardia, they try to break the rhythm by pacing the heart at a rate faster than its intrinsic rate, a strategy anti-tachycardia pacing.

Anti-tachycardia pacing is very low energy, so low that patients may not even sense it. But it is relatively ineffective when the heart is beating 200 time per minute or faster. At these higher rates, the ICS zaps the heart with a strong electrical shock that resets it and, with luck, allows the pacemaker node to restart it with a normal rhythm.

A novel electrotherapy

The scientists knew from earlier experiments that the voltage needed to shut down ventricular tachycardia depended on the timing of the shock. This led them to ask whether a sequence of multiple, closely timed low-voltage shocks might be more effective than a single high-voltage shock, and be less sensitive to timing.

Indeed it turned out that if they shocked the heart multiple times they could reduce the peak shock amplitude from well over 200 volts to 20 volts, timing no longer mattered, and the therapy worked even if the ventricular tachycardia was very rapid.

Although this electrotherapy involves multiple shocks, the total energy it delivers is still lower than that of a single large shock, roughly 80 times lower.

Why do multiple shocks work better? Arrhythmias generate electrical wave vortices – little electrical tornadoes in the heart – and it is these vortices, or re-entrant circuits, that make the heart beat too fast and prevent it from pumping properly.

But immediately after it contracts, heart muscle goes through a refractory, or unresponsive, period during which it does not respond to electrical stimulation. The multiple shocks may do a better job of extinguishing the re-entrant circuits by creating an area of unresponsive muscle into which the re-entrant wavefront -the electrical tornado – crashes, the scientists suggest.

Relocating the Electrodes

Defibrillators now on the market apply shocks between the right ventricle (RV) and an “active can” located above the chest wall, below the collarbone. The shocks are painful in part because they pass through the chest wall muscle and sensory nerves.

The investigators found they could reduce peak shock voltages by an additional 50 percent if they applied shocks between the RV and coronary sinus (CS), a vessel that collects deoxygenated blood from the heart muscle, rather than through the chest wall. Less energy was required because the shocks were confined to the heart itself, and for the same reason they were also less painful.

In an earlier paper, Efimov’s student Wenwen Li, PhD, now at St. Jude Medical, had reported on a similar strategy for restoring the rhythm of the atria, the two upper chambers of the heart, for a less serious but more common rhythm abnormality.

The team has already developed the first low-energy atrial defibrillator, which will soon be entering clinical trials. They hope for similarly rapid progress with the ventricular defibrillator.

“We think this technology can and will be implemented soon,” says Janardhan. “There’s a lot of cardiac research that may pan out 20 or 30 years from now,” he says, “but as a physician I want something that can help my patients now.”

Source : http://www.news-medical.net/news/20121113/Novel-electrotherapy-reduces-energy-needed-to-re-establish-normal-rhythm-in-the-heart.aspx

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Positive results from BioCardia’s Helical Infusion System Phase 1/2 trial on ischemic cardiomyopathy

Positive results from BioCardia’s Helical Infusion System Phase 1/2 trial on ischemic cardiomyopathy

BioCardia, Inc., focused on regenerative biologic therapies for cardiovascular disease, today announced positive results from a Phase 1/2 heart failure trial using the Company’s Helical Infusion System, comprising the Helical Infusion System Catheter™ and Morph® Vascular Access Catheter, to deliver allogeneic, or “off-the-shelf,” and autologous, or from the treated patient, mesenchymal (adult) stem cells (MSCs) via transendocardial injection. According to the results, both the allogeneic and autologous MSCs were safe and well-tolerated at all doses and demonstrated similarly positive effects on cardiac structure and function, patient functional capacity and quality of life. Results from the POSEIDON (Percutaneous Stem Cell Injection Delivery Effects on Neomyogenesis) study were reported in a late breaker presentation titled, “Randomized Comparison of Allogeneic vs Autologous Mesenchymal Stem Cells in Patients with Ischemic Cardiomyopathy,” at the American Heart Association’s 2012 Scientific Sessions and have been published in an article in the November 6 edition of the Journal of the American Medical Association. The POSEIDON study was cosponsored by the NIH Specialized Center for Cell Therapy, the University of Miami, and BioCardia.

Joshua Hare, M.D., Director of the Interdisciplinary Stem Cell Institute (ISCI) at the University of Miami Miller School of Medicine, and the POSEIDON study lead principal investigator, stated, “The combination of Allogenic MSCs with the BioCardia Helix catheter has enormous potential as a combination product for treating heart failure. The strong safety results and ease of the catheter delivery procedure in skilled hands, coupled with the potential for the use of allogeneic stem cells, suggest that this procedure may one day be as easy to perform as coronary angioplasty.”

Peter Altman, Ph.D., President and CEO of BioCardia, commented, “The Helical Infusion System is intended to be the safest and easiest to use catheter for multiple clinical applications in cell- and gene-based therapy. We believe its performance and our track record of experience are second to none, and we are very optimistic about the delivery mesenchymal stem cells for the treatment of ischemic heart failure. Trial results such as POSEIDON require the talent and hard work of a dedicated team of experts, and we have been privileged to work with the clinical teams at the University of Miami and Johns Hopkins University.”

Interventional cardiologist co-authors who performed the procedures in the study included Alan W. Heldman, M.D., and Juan Pablo Zambrano, M.D., at the University of Miami Miller School of Medicine, and Jeffrey A Brinker, M.D., and Peter VanDoren Johnston, M.D., at the Johns Hopkins University School of Medicine.

The Phase 1/2 POSEIDON study enrolled 31 patients with chronic ischemic left ventricular (LV) dysfunction due to ischemic cardiomyopathy (ICM). Patients were randomized to receive one of three different dose levels (20, 100, or 200 million cells) of either allogeneic MSCs or autologous MSCs. The stem cells were delivered to 10 LV sites in the myocardium by BioCardia’s transendocardial stem cell injection (TESI) during retrograde left heart catheterization using BioCardia’s Helical Infusion Catheter. The two catheter system fixates to the heart wall via a corkscrew needle, allowing for stable and controlled delivery of biologic therapies to the heart.

Following BioCardia’s TESI, patients were hospitalized for a minimum of four days and were seen two weeks post-catheterization. Thereafter, safety and efficacy assessments using cardiac imaging studies, exercise peak VO2, a 6-minute walk test, New York Heart Association (NYHA) Class and the Minnesota Living with Heart Failure (MLHF) questionnaire were performed on a monthly basis for six months and then again at 12 months. After 13 months, all patients received follow-up CT scans of the heart, chest, abdomen and pelvis.

The primary objective of the study was to demonstrate the safety of allogeneic MSCs administered by BioCardia’s TESI, determined by the incidence of any treatment-emergent serious adverse events (TE-SAEs) one month after stem cell injection. Data showed that within 30 days, one patient in each cohort was hospitalized for heart failure, a TE-SAE rate of 6.7%, substantially less than the pre-specified stopping rate of 25%. The secondary objectives were to compare the long-term safety of allogeneic MSCs to autologous MSCs and to demonstrate the efficacy of allogeneic MSCs and autologous MSCs administered by TESI in these patients. The one-year incidence of serious adverse events was not different between cell types, except for fewer ventricular arrhythmias in allogeneic recipients. Relative to baseline, allogeneic and autologous MSC therapy similarly improved the 6-minute walk and the MLHF questionnaire score, but not the exercise VO2 max. Finally, MSCs reduced infarct size (33.2%; P<0.0001), left ventricular (LV) volumes and sphericity index similarly in allogeneic and autologous groups. Importantly, allogeneic MSCs did not stimulate significant donor-specific alloimmune reactions.

A parallel Phase 1/2 study – the Transendocardial Autologous Cells in Heart Failure Trial (TAC-HFT) – also enabled by the BioCardia Helical Infusion System. The trial, co-sponsored by the University of Miami, is comparing autologous (bone marrow or mesenchymal) cell delivery to placebo in up to 68 cardiomyopathy patients randomized under a protocol similar to that of the POSEIDON trial. Early results in a first cohort of patients (N=8) were reported in 2011 to show that the autologous cells effected remodeling of LV shape and restoration of normal LV proportions.

Source : http://www.news-medical.net/news/20121107/Positive-results-from-BioCardias-Helical-Infusion-System-Phase-12-trial-on-ischemic-cardiomyopathy.aspx

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AeriSeal System appears to be effective in treating emphysema

AeriSeal System appears to be effective in treating emphysema

Researchers at the University of Alabama at Birmingham injected a foam sealant into the lungs of a former smoker on Oct. 29, 2012, to treat his worsening emphysema. He was the first patient in the United States treated in a late-stage clinical trial of the AeriSeal System. The therapy, approved for use in parts of Europe and Israel, is undergoing investigation in the U.S. as a potential method of reducing lung volume in patients with severe emphysema.

Emphysema, a lung disease usually caused by smoking, damages air sacs in the lung called alveoli. The sacs fill with air that the body is unable to exhale, causing the lungs to expand. This in turn flattens the diaphragm, the primary muscle used for breathing. The flattened diaphragm is unable to function properly, making it extremely difficult for the individual to breathe. An estimated 4.9 million Americans have been diagnosed with emphysema.

A treatment known as lung volume reduction surgery has been employed to treat emphysema with some success. In the procedure, diseased portions of the lungs are surgically removed, allowing the lungs to return to a more normal size. This in turn allows the diaphragm to resume normal function. However, lung volume reduction surgery comes with substantial risk, including a 50 percent risk of major cardiac or pulmonary complications.

“We have been in search of a less-invasive way to achieve the same goal of lung reduction, without the risks inherent in surgery,” says Mark Dransfield, M.D., associate professor in the division of Pulmonary, Allergy and Critical Care Medicine and primary investigator in the new study.

The AeriSeal System treatment is performed via a standard bronchoscopy, in which a bronchoscope is used to thread a catheter through the patient’s airway to the most diseased areas of the lung. The foam, a proprietary polymer, comes in two liquid parts which are mixed together moments before injection. The addition of air to the mixture produces the foam. Within about 30 minutes of injection, the foam hardens to a rubbery consistency, blocking off the holes in the air sacs and causing sealing the damaged regions of lung. Over the course of several weeks, the air sacs deflate and the lung shrinks in size, clearing the way for the diaphragm to return to normal function.

“Based on previous studies and experience overseas, the AeriSeal System appears to be nearly as effective as lung volume reduction surgery without the more significant risks of surgery,” says Dransfield. “The main side effect of this therapy is an immune system inflammatory response with flu-like symptoms that resolves over the course of two or three days.”

Source : http://www.news-medical.net/news/20121103/AeriSeal-System-appears-to-be-effective-in-treating-emphysema.aspx

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Researchers combine robotics, machine learning and brain imaging to assist infants with CP

Researchers combine robotics, machine learning and brain imaging to assist infants with CP

Learning to crawl comes naturally for most infants, but those with cerebral palsy lack the muscle strength and coordination to perform the 25 individual movements required for crawling. With a $1.135 million, three-year grant from the National Science Foundation’s National Robotics Initiative, University of Oklahoma researchers from the Norman and Health Sciences Center campuses are combining robotics, machine learning and brain imaging to assist infants with CP with the challenging, life-altering skill.

“Because infants with CP are unable to reliably perform the individual movements that make up crawling behavior, they learn to stop trying instead of continuing to practice these movements,” said Project Leader Andrew Fagg, associate professor in the OU departments of Computer Science and Bioengineering and project leader. “This substantially delays their development of skilled crawling. In turn, cognitive development and other areas of development are delayed because they both rely on the infants being able to explore their surrounding world.”

“In our previous study, we were able to capture many of the infant’s actions and had a robot that could assist some of the infant’s attempts at crawling. These assists serve as rewards that encourage continued practice of specific limb movements. This grant will allow us, among other things, to develop new robot platforms that can allow a greater range of infant mobility” said David Miller, professor in the OU departments of Aerospace and Mechanical Engineering and Bioengineering. “In the latter part of this grant, we will also start working with the transition from crawling to walking.”

“This grant is also important because it builds on and expands our previous work that maximizes the interaction of robotics with what an infant can do,” said Thubi Kolobe, professor of rehabilitative sciences at the OU Health Sciences Center College of Allied Health. “Infant learning is integral, and when infants stop trying, parts of the brain responsible for the skill are negatively affected. The next step of this research is to increase the level of help that infants with or at risk for CP are getting. We are looking for combinations of assists that result in the best incentives for these infants. We also want to see if there is a connection between what the infants are learning and what is happening in the brain.”

Lei Ding, assistant professor in the OU departments of Electrical Engineering and Bioengineering, will then perform brain scans using electroencephalograph to determine how the infants’ brains respond when they are assisted by the robotic device. The EEG technology will assess brain activity of infants during crawling and provide information about changes that occur because of robotics assists and infant efforts.

“Beginning in spring 2013, we will conduct clinical trials to test six infants without CP on the new crawling robot,” says Kolobe. “Then, one year later, we will conduct clinical trials to test 24 CP infants on the crawling robot. Initial tests on standing and walking with infants without CP will be conducted by the end of the project. No CP infants will be tested on standing and walking in this grant, only healthy infants.”

“This is groundbreaking research, and no one else in the world is doing it,” says Kolobe. “We want to invite anyone with an infant who is at risk for CP or severe developmental delays, between four and eight months old, who is interested in participating in these clinical trials to contact Dr. Thubi H.A. Kolobe, at 405-271-2131 ext. 47121 or hkolobe@ouhsc.edu.”

Source : http://www.news-medical.net/news/20121102/Researchers-combine-robotics-machine-learning-and-brain-imaging-to-assist-infants-with-CP.aspx

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Diffusion tensor imaging detects complex muscle structures in 3D

Diffusion tensor imaging detects complex muscle structures in 3D

Eindhoven University of Technology (TU/e) and the Academic Medical Center (AMC) in Amsterdam have together developed a technique that allows detailed 3D imaging of complex muscle structures of patients. It also allows muscle damage to be detected very precisely. This new technique opens the way to much better and more patient-friendly diagnosis of muscular diseases. It also allows accurate, non-invasive muscle examinations among top athletes. Martijn Froeling received a PhD for this research at TU/e on Monday 29 October.

Froeling uses diffusion tensor imaging (DTI), an MRI technique that allows the movements of water molecules in living tissue to be viewed. Because muscles are made of fibers, the movements of water molecules in the direction of the fibers are different from those in other directions. This characteristic allows muscles to be imaged with a high level of detail. This was already possible on a small scale with simple muscles, but thanks to Froeling’s work it can now also be done on a larger scale and with complex muscle structures. More importantly, this improved technique also reveals very small muscle damage, because of the different movements of the water molecules in damaged muscle fibers.

3D images

To reach these results, Froeling improved the data acquisition process – the way the MRI scanner images the muscle under examination. This has to be performed relatively quickly, because it is uncomfortable for patients to lie in an MRI scanner for a long time, but at the same time it has to provide sufficiently detailed data. He also improved the processing of the acquired data into reliable 3D images. Physicians can now easily view complex muscle structures from all angles on-screen. No new equipment was needed; the researchers used standard widely available clinical systems.

Marathon runners

As a practical study, Froeling imaged a range of subjects including the thighs of marathon runners at different times: one week before a marathon, two days after it, and again three weeks after. He was able to visualize the muscle damage following the marathon. This was still visible after three weeks, even though the runners themselves in many cases no longer reported any pain in their muscles. Another study was of the pelvic floor in women; a good example of a highly complex muscle structure. The technique has proved to be capable of imaging this structure with great accuracy, which makes it potentially very valuable for the diagnosis of conditions such as uterine prolapse.

Wide application area

AMC Amsterdam and TU/e now intend to use this technique in studies of post polio syndrome and spinal muscular atrophy. Froeling believes there are numerous potential applications: there are around 600 different types of muscle disease and damage, and the new technique will improve the ability to study these. However further studies will first be needed: although the technique allows muscle disease or injury to be imaged it does not reveal the precise cause, which may be tearing, fat infiltration or other abnormalities. Clarification is also still needed on what are the normal values for healthy men and women of different ages, to provide a reference framework for identifying abnormalities in different groups of patients. Another kind of application is in examinations of top athletes, to allow timely detection of muscle damage or better estimation of the recovery time needed after injuries.

source : http://www.news-medical.net/news/20121031/Diffusion-tensor-imaging-detects-complex-muscle-structures-in-3D.aspx

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Inspired by Segway Scooter, Vanderbilt Exoskeleton Gets Paralyzed on Their Legs

Inspired by Segway Scooter, Vanderbilt Exoskeleton Gets Paralyzed on Their Legs

The dream of regaining the ability to stand up and walk has come closer to reality for people paralyzed below the waist who thought they would never take another step.

A team of engineers at Vanderbilt University’s Center for Intelligent Mechatronics has developed a powered exoskeleton that enables people with severe spinal cord injuries to stand, walk, sit and climb stairs. Its light weight, compact size and modular design promise to provide users with an unprecedented degree of independence.

The university has several patents pending on the design and Parker Hannifin Corporation – a global leader in motion and control technologies – has signed an exclusive licensing agreement to develop a commercial version of the device, which it plans on introducing in 2014.

Parker-Hannifin design concept for the commercial version of the exoskeleton.

Parker-Hannifin design concept for the commercial version of the exoskeleton. (Courtesy of Parker-Hannifin)

According to the National Spinal Cord Injury Statistical Center, somewhere between 236,000 to 327,000 people in the U.S. are living with serious spinal cord injuries. About 155,000 have paraplegia. The average age at injury is 41 and the estimated lifetime cost when it happens to a person of 50 ranges from $1.1 million to $2.5 million.

Until recently “wearable robots” were the stuff of science fiction. In the last 10 years, however, advances in robotics, microelectronics, battery and electric motor technologies advanced to the point where it has become practical to develop exoskeletons to aid people with disabilities. In fact, two companies – Argo Medical Technologies Ltd. in Israel and Ekso Bionics in Berkeley, Calif. – have developed products of this type and are marketing them in the U.S.

These devices act like an external skeleton. They strap in tightly around the torso. Rigid supports are strapped to the legs and extend from the hip to the knee and from the knee to the foot. The hip and knee joints are driven by computer-controlled electric motors powered by advanced batteries. Patients use the powered apparatus with walkers or forearm crutches to maintain their balance.

“You can think of our exoskeleton as a Segway with legs,” said Michael Goldfarb, the H. Fort Flowers Chair in Mechanical Engineering and professor of physical medicine and rehabilitation. “If the person wearing it leans forward, he moves forward. If he leans back and holds that position for a few seconds, he sits down. When he is sitting down, if he leans forward and holds that position for a few seconds, then he stands up.”

Goldfarb developed the system with funding from the National Institutes of Health and with the assistance of research engineer Don Truex, graduate students Hugo Quintero, Spencer Murray and Kevin Ha, and Ryan Farris, a former student who now works for Parker Hannifin.

“My kids have started calling me ‘Ironman,’” said Brian Shaffer, who was completely paralyzed from the waist down in an automobile accident on Christmas night 2010. He has been testing the Vanderbilt apparatus at the Nashville-area satellite facility of the Shepherd Center. Based in Atlanta, Shepherd Center is one the leading hospitals for spinal cord and brain injury rehabilitation in the U.S. and has provided the Vanderbilt engineers with the clinical feedback they need to develop the device.

Brian Shaffer

Brian Shaffer testing the Vanderbilt exoskeleton at Shepherd Center’s satellite facility in Franklin, Tenn. (Joe Howell/Vanderbilt)

“It’s unbelievable to stand up again. It takes concentration to use it at first but, once you catch on, it’s not that hard: The device does all the work. I don’t expect that it will completely replace the wheelchair, but there are some situations, like walking your daughter down the aisle at her wedding or sitting in the bleachers watching your son play football, where it will be priceless,” said Shaffer, who has two sons and two daughters.

“This is an extremely exciting new technology,” said Clare Hartigan, a physical therapist at Shepherd Center who has worked with the Argo, Ekso and Vanderbilt devices. “All three models get people up and walking, which is fantastic.”

According to Hartigan, just getting people out of their wheelchairs and getting their bodies upright regularly can pay major health dividends. People who must rely on a wheelchair to move around can develop serious problems with their urinary, respiratory, cardiovascular and digestive systems, as well as getting osteoporosis, pressure sores, blood clots and other afflictions associated with lack of mobility. The risk for developing these conditions can be reduced considerably by regularly standing, moving and exercising their lower limbs.

The Vanderbilt design has some unique characteristics that have led Hartigan and her colleagues at Shepherd Center to conclude that it has the most promise as a rehabilitative and home device.

None of the exoskeletons have been approved yet for home use. But the Vanderbilt design has some intrinsic advantages. It has a modular design and is lighter and slimmer than the competition. As a result, it can provide its users with an unprecedented degree of independence. Users will be able to transport the compact device on the back of their wheelchair. When they reach a location where they want to walk, they will be able to put on the exoskeleton by themselves without getting out of the wheelchair. When they are done walking, they can sit back down in the same chair and take the device off or keep it on and propel the wheelchair to their next destination.

The Vanderbilt exoskeleton weighs about 27 pounds, nearly half the weight of the other models that weigh around 45 pounds. The other models are also bulkier so most users wearing them cannot fit into a standard-sized wheelchair.

From a rehabilitation perspective the Vanderbilt design also has two potential advantages, Hartigan pointed out:

The amount of robotic assistance adjusts automatically for users who have some muscle control in their legs. This allows them to use their own muscles while walking. When a user is totally paralyzed, the device does all the work. The other designs provide all the power all of the time.

It is the only wearable robot that incorporates a proven rehabilitation technology called functional electrical stimulation. FES applies small electrical pulses to paralyzed muscles, causing them to contract and relax. FES can improve strength in the legs of people with incomplete paraplegia. For complete paraplegics, FES can improve circulation, change bone density and reduce muscle atrophy.

There is also the matter of cost. The price tags of other rehabilitation model exoskeletons have been reported to be as high as $140,000 apiece, plus a hefty annual service fee. Parker Hannifin hasn’t set a price for the Vanderbilt exoskeleton, but Goldfarb is hopeful that its minimalist design combined with Parker Hannifin’s manufacturing capability will translate into a more affordable product. “It would be wonderful if we could get the price down to a level where individuals could afford them and insurance companies would cover them,” he said.

Meanwhile, Hartigan has advice for potential users: “These new devices for walking are here and they are getting better and better. However, a person has to be physically fit to use them. They have to keep their weight below 220 pounds, develop adequate upper body strength to use a walker or forearm crutches and maintain flexibility in their shoulder, hip, knee and ankle joints … which is not that easy when a person has relied on a wheelchair for months or even years.”

This is the first of several posts on companies and technologies featured at the AdvaMed 2012 conference held earlier this week in Boston, MA. At the conference, it was announced that Israeli-founded exoskeleton technology leader, ARGO, has selected Massachusetts as its U.S. headquarters.

ARGO Medical Technologies’ Rewalk exoskeleton, which we have covered recently, enables persons with lower limb disabilities, such as paraplegia, to stand and walk independently without assistance.

According to the ARGO press release:

At the press conference, U.S. Army Veteran Theresa Hannigan demonstrated the ReWalk exoskeleton technology. Hannigan is a former Army Sergeant, who served during the Vietnam era and was left paralyzed two years ago as a result of a progressive autoimmune disease that she contracted while in the Army. Hannigan has been training with the ReWalk at the National Center of Excellence for the Medical Consequences of Spinal Cord Injury at the James J. Peters V.A. Medical Center in Bronx, New York, and is planning to use the exoskeleton on October 20, 2012 to walk a one-mile road race in Lindenhurst, New York, to raise money for the organization “Hope for the Warriors,” which helps U.S. service men and women.”

Source : http://news.vanderbilt.edu/2012/10/exoskeleton/

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Barostim neo Baroreflex Stimulator Receives CE Approval for Treatment of Hypertension

Barostim neo Baroreflex Stimulator Receives CE Approval for Treatment of Hypertension

Barostim neo Baroreflex Stimulator Receives CE Approval for Treatment of Hypertension

More interesting news coming our way from the American Heart Association 2006 Scientific Sessions in Chicago. Research done by the University of Rochester Medical Center shows that Rheos™ Baroreflex Hypertension Therapy™ System, a product of CVRx®, Inc., shows promise for drug resistant hypertensives. As we have previously reported, the investigational device by a Minneapolis, MN company functions through activation of carotid baroreceptors, and is implanted surgically.

rheos main Positive Results from Trial of Rheos Baroreflex Hypertension Therapy

Here’s what University of Rochester says about its research:

The trial is designed to assess device safety and efficacy in patients with systolic blood pressure of 160 mmHg or greater, despite being on at least three anti-hypertension medications, including one diuretic. The presentation reported on the first 10 U.S. patients enrolled in the trial. After one month of surgical recovery, baseline blood pressure was assessed and the device was activated. Three months of active Rheos therapy reduced systolic blood pressure by an average of 22 mmHg (180 mmHg vs. 158 mmHg) and diastolic blood pressure by an average of 18 mmHg (105 mmHg vs. 87 mmHg), using office cuff measurements. The implants were well tolerated and there were no unanticipated serious adverse events related to the system or procedure.

CVRx has received the European CE Mark of approval for its second-generation implantable anti-hypertensive barostimulation device, the Barostim neo. It is the successor of their RHEOS baroreflex stimulation device, which we have covered several times before. Compared to its predecessor, it features a new unilateral 1mm electrode and a smaller, more advanced stimulator. The stimulator is implanted underneath the pectoralis muscle, with a subfascial lead running to the carotid sinus. The system works by electrically activating the baroreceptors located on the carotid artery. This makes the body’s own blood pressure regulation mechanisms decrease blood pressure by reduction of the sympathetic tone, leading to a peripheral vasodilation, lower heart rate and increased fluid excretion by the kidneys.

The device is approved for hypertension resistant to medical therapy only, meaning for now it is limited to a relatively small, well-defined patient group. Results with the RHEOS device have been positive, with reductions in blood pressure in the order of 20/10 mmHg on top of maximal medical therapy. In addition there are indications that the device might be effective in treating certain forms of heart failure. The latest results with the Barostim neo will be presented on August 30 at the European Society of Cardiology (ESC) Congress 2011.

Source : http://www.cvrx.com/pdf/meetings/CVRx_Hypertension_Press_Release_Final.pdf

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CardioKinetix Parachute for Percutaneous Ventricular Restoration Fully Cleared in EU

CardioKinetix Parachute for Percutaneous Ventricular Restoration Fully Cleared in EU

CardioKinetix Parachute for Percutaneous Ventricular Restoration Fully Cleared in EU

CardioKinetix has developed a novel transcatheter implant called Parachute Ventricular Partitioning Device, which already received the CE mark and has now won approval for two additional sizes. The Parachute is a partitioning membrane deployed within the compromised ventricle that is intended to treat heart failure resulting from myocardial infarction.

parachute CardioKinetix Receives Expanded CE Approval for Parachute Percutaneous Left Ventricular Partitioning DeviceThe Parachute consists of a synthetic fluoropolymer (ePTFE) membrane stretched over a nitinol frame. The idea behind the device is that it partitions the damaged muscle, isolating the non-functional muscle segment from the functional segment, which decreases the overall volume and restores a more normal geometry and function in the left ventricle.

Early trials have shown the Parachute to decrease heart failure symptoms and increase exercise capacity and quality of life, with additional trials underway. If indeed proven effective, this could be an important addition to the interventional cardiologist’s toolbox.

The Parachute™ is a catheter based partitioning device deployed within the left ventricle for patients who have developed ischemic heart failure following a heart attack. The Parachute™ implant partitions the damaged muscle, isolating the non-functional muscle segment from the functional segment, which decreases the overall volume and restores a more normal geometry and function in the left ventricle.

The Parachute™ implant is comprised of a fluoropolymer (ePTFE) membrane stretched over a nitinol frame. The device is deployed into the apex of the left ventricle and partitions off the portion of the ventricle affected by the damaged myocardium in order to treat patients with ischemic heart failure.

The Parachute™ is a catheter based partitioning device deployed within the left ventricle for patients who have developed ischemic heart failure following a heart attack. The Parachute™ implant partitions the damaged muscle, isolating the non-functional muscle segment from the functional segment, which decreases the overall volume and restores a more normal geometry and function in the left ventricle.

The Parachute™ implant is comprised of a fluoropolymer (ePTFE) membrane stretched over a nitinol frame. The device is deployed into the apex of the left ventricle and partitions off the portion of the ventricle affected by the damaged myocardium in order to treat patients with ischemic heart failure.

Source : http://www.cardiokinetix.com/products-devices/

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