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Google patent filing proposes device in eye to address poor vision

Google patent filing proposes device in eye to address poor vision | Amazing Science | Scoop.it

What are Google's visionaries up to these days? You may be sorry you asked. Discovery reported that an electronic device injected into an eyeball is the focus of a patent filed by Google.

 

The Google patent application was reported in Forbes. Aaron Tilley said "the device is injected in fluid that then solidifies to couple the device with the eye's lens capsule, the transparent membrane surrounding the lens." The device is injected into the eye and it has tiny components, said Lilley: storage, sensors, radio, battery and an electronic lens. The device gets power wirelessly from an "energy harvesting antenna."

 

"The whole endeavor appears to be a way of correcting poor vision," saidDiscovery. Tilley at Forbes said, "According to the patent, the electronic lens would assist in the process of focusing light onto the eye's retina." The inventor in the application is listed as Andrew Jason Conrad.

 

The patent application said, "Elements of the human eye (e.g., the cornea, lens, aqueous and vitreous humor) operate to image the environment of the eye by focusing light from the environment onto the retina of the eye, such that images of elements of the environment are presented in-focus on the retina. The optical power of the natural lens of the eye can be controlled (e.g., by ciliary muscles of the eye) to allow objects at different distances to be in focus at different points in time (a process known as accommodation)."

 

A variety of reasons, however, are behind decreased focus and degradation of images presented to the retina. "Issues with poor focus can be rectified by the use of eyeglasses and/or contact lenses or by the remodeling of the cornea. Further, artificial lenses can be implanted into the eye (e.g., into the space in front of the iris, into the lens capsule following partial or full removal of the natural lens, e.g., due to the development of cataracts) to improve vision."

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SkinHaptics: Research brings ‘smart hands’ closer to reality

SkinHaptics: Research brings ‘smart hands’ closer to reality | Amazing Science | Scoop.it

Using your skin as a touchscreen has been brought a step closer after UK scientists successfully created tactile sensations on the palm using ultrasound sent through the hand. The University of Sussex-led study -- funded by the Nokia Research Centre and the European Research Council -- is the first to find a way for users to feel what they are doing when interacting with displays projected on their hand. This solves one of the biggest challenges for technology companies who see the human body, particularly the hand, as the ideal display extension for the next generation of smartwatches and other smart devices.

 

Current ideas rely on vibrations or pins, which both need contact with the palm to work, interrupting the display. However, this new innovation, called SkinHaptics, sends sensations to the palm from the other side of the hand, leaving the palm free to display the screen. The device uses 'time-reversal' processing to send ultrasound waves through the hand. This technique is effectively like ripples in water but in reverse -- the waves become more targeted as they travel through the hand, ending at a precise point on the palm.

 

It draws on a rapidly growing field of technology called haptics, which is the science of applying touch sensation and control to interaction with computers and technology. Prof Sriram Subramanian, who leads the research team at the University of Sussex, says that technologies will inevitably need to engage other senses, such as touch, as we enter what designers are calling an 'eye-free' age of technology. He says: "Wearables are already big business and will only get bigger. But as we wear technology more, it gets smaller and we look at it less, and therefore multisensory capabilities become much more important. "If you imagine you are on your bike and want to change the volume control on your smartwatch, the interaction space on the watch is very small. So companies are looking at how to extend this space to the hand of the user. "What we offer people is the ability to feel their actions when they are interacting with the hand."

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A global network of millions of genomes could be medicine’s next great advance

A global network of millions of genomes could be medicine’s next great advance | Amazing Science | Scoop.it

Noah is a six-year-old child suffering from a disease without a name. This year, his physicians will begin sending his genetic information across the Internet to see if there’s anyone, anywhere, in the world like him. A match could make a difference. Noah is developmentally delayed, uses a walker, speaks only a few words. And he’s getting sicker. MRIs show that his cerebellum is shrinking. His DNA was analyzed by medical geneticists at the Children’s Hospital of Eastern Ontario. Somewhere in the billions of DNA letters is a misspelling, and maybe the clue to a treatment. But unless they find a second child with the same symptoms, and a similar DNA error, his doctors can’t zero in on which mistake in Noah’s genes is the crucial one.

 

Programmers in Toronto recently began testing a system for trading genetic information with other hospitals. These facilities, in locations including Miami, Baltimore, and Cambridge, U.K., also treat children with so-called ­Mendelian disorders, which are caused by a rare mutation in a single gene. The system, called MatchMaker Exchange, represents something new: a way to automate the comparison of DNA from sick people around the world. One of the people behind this project is David Haussler, a bioinformatics expert based at the University of California, Santa Cruz. The problem Haussler is grappling with now is that genome sequencing is largely detached from our greatest tool for sharing information: the Internet. That’s unfortunate because more than 200,000 people have already had their genomes sequenced, a number certain to rise into the millions in years ahead. The next era of medicine depends on large-scale comparisons of these genomes, a task for which he thinks scientists are poorly prepared. “I can use my credit card anywhere in the world, but biomedical data just isn’t on the Internet,” he says. “It’s all incomplete and locked down.” Genomes often get moved around in hard drives and delivered by FedEx trucks.

 

Haussler is a founder and one of the technical leaders of the Global Alliance for Genomics and Health, a nonprofit organization formed in 2013 that compares itself to the W3C, the standards organization devoted to making sure the Web functions correctly. Also known by its unwieldy acronym, GA4GH, it’s gained a large membership, including major technology companies like Google. Its products so far include protocols, application programming interfaces (APIs), and improved file formats for moving DNA around the Web. But the real problems it is solving are mostly not technical. Instead, they are sociological: scientists are reluctant to share genetic data, and because of privacy rules, it’s considered legally risky to put people’s genomes on the Internet.

 

But pressure is building to use technology to study many, many genomes at once and begin to compare that genetic information with medical records. That is because scientists think they’ll need to sort through a million genomes or more to solve cases—like Noah’s—that could involve a single rogue DNA letter, or to make discoveries about the genetics of common diseases that involve a complex combination of genes. No single academic center currently has access to information that extensive, or the financial means to assemble it.

 

Haussler and others at the alliance are betting that part of the solution is a peer-to-peer computer network that can unite widely dispersed data. Their standards, for instance, would permit a researcher to send queries to other hospitals, which could choose what level of information they were willing to share and with whom. This control could ease privacy concerns. Adding a new level of complexity, the APIs could also call on databases to perform calculations—say, to reanalyze the genomes they store—and return answers.

 

The largest labs can now sequence human genomes to a high polish at the pace of two per hour. The first genome took about 13 years just 2 decades ago. Back-of-the-envelope calculations suggest that fast machines for DNA sequencing will be capable of producing 85 petabytes of data this year worldwide, twice that much in 2019, and so on. For comparison, all the master copies of movies held by Netflix take up 2.6 petabytes of storage.

 

“This is a technical question,” says Adam Berrey, CEO of Curoverse, a Boston startup that is using the alliance’s standards in developing open-source software for hospitals. “You have what will be exabytes of data around the world that nobody wants to move. So how do you query it all together, at once? The answer is instead of moving the data around, you move the questions around. No industry does that. It’s an insanely hard problem, but it has the potential to be transformative to human life.”

 

Last summer Haussler’s alliance launched a basic search engine for DNA, which it calls Beacon. Currently, Beacon searches through about 20 databases of human genomes that were previously made public and have implemented the alliance’s protocols. Beacon offers only yes-or-no answers to a single type of question. You can ask, for instance, “Do any of your genomes have a T at position 1,520,301 on chromosome 1?” “It’s really just the most basic question there is: have you ever seen this variant?” says Haussler. “Because if you did see something new, you might want to know, is this the first patient in the world that has this?” Beacon is already able to access the DNA of thousands of people, including hundreds of genomes put online by Google.

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Stanford scientists develop new technique for imaging cells and tissues under the skin

Stanford scientists develop new technique for imaging cells and tissues under the skin | Amazing Science | Scoop.it
Scientists have many tools at their disposal for looking at preserved tissue under a microscope in incredible detail, or peering into the living body at lower resolution. What they haven't had is a way to do both: create a three-dimensional real-time image of individual cells or even molecules in a living animal.

Now, Stanford scientists have provided the first glimpse under the skin of a living animal, showing intricate real-time details in three dimensions of the lymph and blood vessels.

The technique, called MOZART (for MOlecular imaging and characteriZation of tissue noninvasively At cellular ResoluTion), could one day allow scientists to detect tumors in the skin, colon or esophagus, or even to see the abnormal blood vessels that appear in the earliest stages of macular degeneration – a leading cause of blindness.

"We've been trying to look into the living body and see information at the level of the single cell," said Adam de la Zerda, an assistant professor of structural biology at Stanford and senior author on the paper. "Until now there has been no way do that."

De la Zerda, who is also a member of Stanford Bio-X, said the technique could allow doctors to monitor how an otherwise invisible tumor under the skin is responding to treatment, or to understand how individual cells break free from a tumor and travel to distant sites.
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Novel blood test for Alzheimer's diagnosis 15 years before manifestation

Novel blood test for Alzheimer's diagnosis 15 years before manifestation | Amazing Science | Scoop.it
Today, Alzheimer's disease is diagnosed too late. In collaboration with a research team at the university and German Center for Neurogenerative Diseases in Göttingen, Researchers at Ruhr-Universität Bochum have developed a blood test that may potentially facilitate detection of Alzheimer's at an early stage. It is based on an immuno-chemical analysis using an infrared sensor.

 

For the novel test, the secondary structure of the so-called Amyloid beta peptides serves as biomarker. This structure changes in Alzheimer's patients. In the misfolded, pathological structure, more and more Amyloid beta peptides can accumulate, gradually forming visible plaque deposits in the brain that are typical for Alzheimer's disease. This happens more than15 years before first clinical symptoms appear. The pathological beta Amyloid plaques can be temporarily detected by positron emission tomography, short: Amyloid PET; but this procedure is comparatively expensive and is accompanied by radiation exposure.

 

Patented diagnostic method for Alzheimer's detection

Together with Prof Dr med. Jens Wiltfang from Göttingen, the team headed by Prof Dr Klaus Gerwert has developed an infrared sensor for detecting misfolding of Amyloid beta peptides as part of the PhD research projects of Andreas Nabers and Jonas Schartner. The infrared sensor extracts the Amyloid beta peptide from body fluids. The method is patent pending. After initially working with cerebrospinal fluid, the researchers subsequently expanded the method towards blood analysis. "We do not merely select one single possible folding arrangement of the peptide; rather, we detect how all existing Amyloid beta secondarystructures are distributed, in their healthy and in their pathological forms," says Gerwert.

 

Precise diagnostics is not possible until the distribution of all secondary structures is evaluated. Tests that analyse Amyloid beta peptide are already available with so-called enzyme-linked immunosorbent assays (ELISA). They identify the total concentration, percentage of forms of different length, as well as the concentration of individual conformations in body fluids; but they have not, as yet, provided information on the diagnostically relevant distribution of the secondary structures at once. "This is why ELISA tests have not been proven very effective when applied in blood sample analysis in practice," explains Klaus Gerwert.

 

First clinical trials are completed. Using the methods now developed in Bochum and Göttingen, the researchers have analysed samples from 141 patients. They have achieved a diagnostic precision of 84 per cent in the blood and 90 per cent in cerebrospinal fluid, compared with the clinical gold standard. The test revealed an increase of misfolded biomarkers as spectral shift of Amyloid beta band below threshold, thus diagnosing Alzheimer's. "What's unique about it is that this is the only robust label-free test with a single threshold," as Andreas Nabers describes the result of his dissertation.

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Magnetic nanoparticles show promise in biomedical applications

Magnetic nanoparticles show promise in biomedical applications | Amazing Science | Scoop.it
Recent developments and research related to iron oxide nanoparticles confirm their potential in biomedical applications – such as targeted drug delivery – and the necessity for further studies.

 

Iron oxides are widespread in nature and can be readily synthesized in the laboratory. Among them, hematite, magnetite and maghemite nanoparticles have particularly promising properties for biomedical applications.

 

Researchers in China and Korea reviewed recent studies on the preparation, structure and magnetic properties of iron oxide nanoparticles (IONPs) and their corresponding applications. The review, published in the journal Science and Technology of Advanced Materials, emphasized that the size, size distribution (the relative proportions of different-sized particles in a given sample), shape and magnetic properties of IONPs affect the location and mobility of IONPs in the human body. However, having complete control over the shape and size distribution of magnetic IONPs remains a challenge. For example, magnetic IONPs are promising for carrying cancer drugs that target specific tissues. For this to happen, they are coated with a biocompatible shell that carries a specific drug. If this "functionalized" magnetic IONP is too large, it may be cleared from the blood stream. Thus, it is very important to be able to control the size of these particles. Researchers found that IONPs with diameters ranging from 10 to 100 nanometres are optimal for intravenous injection and can remain in the blood stream for the longest period of time.

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Cancer Spread Tracked From A Single Cell In A Live Animal

Cancer Spread Tracked From A Single Cell In A Live Animal | Amazing Science | Scoop.it

Researchers at Harvard-affiliated Boston Children’s Hospital have, for the first time, visualized the origins of cancer from the first affected cell and watched its spread in a live animal. Their work, published in the Jan. 29 issue of Science, could change the way scientists understand melanoma and other cancers and lead to new, early treatments before the cancer has taken hold.


“An important mystery has been why some cells in the body already have mutations seen in cancer, but do not yet fully behave like the cancer,” says the paper’s first author, Charles Kaufman, a postdoctoral fellow in the Zon Laboratory at Boston Children’s Hospital. “We found that the beginning of cancer occurs after activation of an oncogene or loss of a tumor suppressor, and involves a change that takes a single cell back to a stem cell state.”


That change, Kaufman and colleagues found, involves a set of genes that could be targeted to stop cancer from ever starting. The study imaged live zebrafish over time to track the development of melanoma. All the fish had the human cancer mutation BRAFV600E — found in most benign moles — and had also lost the tumor suppressor gene p53.


Kaufman and colleagues engineered the fish to light up in fluorescent green if a gene called crestin was turned on — a “beacon” indicating activation of a genetic program characteristic of stem cells. This program normally shuts off after embryonic development, but occasionally, in certain cells and for reasons not yet known, crestin and other genes in the program turn back on.


“Every so often we would see a green spot on a fish,” said Leonard Zon, director of the Stem Cell Research Program at Boston Children’s and senior investigator on the study. “When we followed them, they became tumors 100 percent of the time.”


When Kaufman, Zon, and colleagues looked to see what was different about these early cancer cells, they found that crestin and the other activated genes were the same ones turned on during zebrafish embryonic development — specifically, in the stem cells that give rise to the pigment cells known as melanocytes, within a structure called the neural crest.


“What’s amazing about this group of genes is that they also get turned on in human melanoma,” said Zon, who is also a member of the Harvard Stem Cell Instituteand a Howard Hughes Medical Institute investigator. “It’s a change in cell fate, back to neural crest status.”


Finding these cancer-originating cells was tedious. Wearing goggles and using a microscope with a fluorescent filter, Kaufman examined the fish as they swam around, shooting video with his iPhone. Scanning 50 fish could take two to three hours. In 30 fish, Kaufman spotted a small cluster of green-glowing cells about the size of the head of a Sharpie marker — and in all 30 cases, these spots grew into melanomas. In two cases, he was able to see on a single green-glowing cell and watch it divide and ultimately become a tumor mass.


Via Steven Krohn
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New gadget analyses your sweat - and it could replace blood tests in future

New gadget analyses your sweat - and it could replace blood tests in future | Amazing Science | Scoop.it

Researchers have developed a prototype that packs five sensors onto a flexible circuit board. The wearable device is able to measure biomarkers in sweat and could one day replace health-monitoring blood tests, scientists have said. By analyzing a person's sweat, the device can measure glucose, lactate - a marker of low oxygen levels in the body - sodium, potassium and skin temperature. The results can be transmitted to wi-fi devices such as smart phones.


Inventor Professor Ali Javey, from the University of California at Berkeley (UC Berkeley), US, said: "Human sweat contains physiologically rich information, thus making it an attractive body fluid for non-invasive wearable sensors. However, sweat is complex and it is necessary to measure multiple targets to extract meaningful information about your state of health. In this regard, we have developed a fully integrated system that simultaneously and selectively measures multiple sweat analytes, and wirelessly transmits the processed data to a smartphone. Our work presents a technology platform for sweat-based health monitors."


Colleague Professor George Brooks, also from UC Berkeley, said: "Having a wearable sweat sensor is really incredible because the metabolites and electrolytes measured by the Javey device are vitally important for the health and well-being of an individual. He explains: "When studying the effects of exercise on human physiology, we typically take blood samples. With this non-invasive technology, someday it may be possible to know what's going on physiologically without needle sticks or attaching little disposable cups on you."

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Nano-shells deliver molecules that tell bone to repair itself

Nano-shells deliver molecules that tell bone to repair itself | Amazing Science | Scoop.it

Scientists at the University of Michigan have developed a polymer sphere that delivers a molecule to bone wounds that tells cells already at the injury site to repair the damage.


Using the polymer sphere to introduce the microRNA molecule into cells elevates the job of existing cells to that of injury repair by instructing the cells' healing and bone-building mechanisms to switch on, said Peter Ma, professor of dentistry and lead researcher on the project. It's similar to a new supervisor ordering an office cleaning crew to start constructing an addition to the building, he said.


Using existing cells to repair wounds reduces the need to introduce foreign cells—a very difficult therapy because cells have their own personalities, which can result in the host rejecting the foreign cells, or tumors. The microRNA is time-released, which allows for therapy that lasts for up to a month or longer, said Ma, who also has appointments in the College of Engineering.


The findings are scheduled for publication in the Jan. 14 issue of Nature Communications. The technology can help grow bone in people with conditions like oral implants, those undergoing bone surgery or joint repair, or people with tooth decay.


"The new technology we have been working on opens doors for new therapies using DNA and RNA in regenerative medicine and boosts the possibility of dealing with other challenging human diseases," Ma said.


Via Carlos Garcia Pando
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Carlos Garcia Pando's curator insight, January 15, 7:00 AM

Good idea: activating cells already present instead of injecting foreign materials

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Blood sample RNA test of platelets presents a new way of detecting cancer

Blood sample RNA test of platelets presents a new way of detecting cancer | Amazing Science | Scoop.it
A new RNA test of blood platelets can be used to detect, classify and pinpoint the location of cancer by analysing a sample equivalent to one drop of blood. Using this new method for blood-based RNA tests of blood platelets, researchers have been able to identify cancer with 96 per cent accuracy and classifying the type of cancer at an accuracy of 71 per cent. This according to a study at Umeå University that has recently been published in the journal Cancer Cell.


“Being able to detect cancer at an early stage is vital. We have studied how a whole new blood-based method of biopsy can be used to detect cancer, which in the future renders an invasive cell tissue sample unnecessary in diagnosing lung cancer, for instance. In the study, nearly all forms of cancer were identified, which proves that blood-based biopsies have an immense potential to improve early detection of cancer,” according to Jonas Nilsson, cancer researcher at Umeå University and co-author of the article.


In the study, researchers from Umeå University, in collaborations with researchers from the Netherlands and the US, have investigated how a new method of blood-based RNA tests of the part of the blood called platelets could be used in detecting and classifying cancer. The results show that blood platelets could constitute a complete and easily accessible blood-based source for sampling and hence be used in diagnosing cancer as well as in the choice of treatment method.


Blood samples from 283 individuals were studied of which 228 people had some form of cancer and 55 showed no evidence of cancer. By comparing the blood samples RNA profiles, researchers could identify the presence of cancer with an accuracy of 96 per cent among patients. Among the 39 patients in the study in which an early detection of cancer had been made, 100 per cent of the cases could be identified and classified.

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New Sepsis Detector Shrinks the Diagnosis from Days to Hours

New Sepsis Detector Shrinks the Diagnosis from Days to Hours | Amazing Science | Scoop.it

Hospitals are beginning to use a new, more potent weapon against sepsis, the devastating condition that kills more than 25 percent of its victims and costs hospitals billions of dollars annually. In the U.S. alone, more than a million people become infected each year, and it contributes to as many half of all deaths in hospitals.


Last fall, the U.S. Food and Drug Administration approved the new technology, developed by T2 Biosystems, for diagnosing sepsis caused by a fungus calledCandida. Several hospitals have begun deploying T2’s Candida-detection system, which is based on the same physical principle behind magnetic resonance imaging. By the end of this year the company aims to have 30 hospitals signed on to purchase and use the technology.


Sepsis is a destructive reaction to an infection marked by an overwhelming inflammatory response throughout the body. If left untreated, sepsis can cause organ malfunction and death. Treating a septic patient requires pinpointing the bacterial or fungal organism that is the root cause. Today that process takes at least a day, and can take up to five days, as the patient’s condition worsens. T2 Biosystems says its novel pathogen detector, called T2 Magnetic Resonance (T2MR), can identify the bug within five hours.


Doctors typically give a septic patient an immediate dose of a so-called broad-spectrum antibiotic that kills a variety of different bacteria, and then try to figure out the specific bug at fault by drawing blood and performing a lab test called a blood culture. At that point it is a race against the unidentified pathogen, and the blood culture step, which often doesn’t work, simply takes too long, says T2 Biosystems CEO John McDonough. McDonough cites clinical data that implies that if patients can get the right drug within 12 hours of first showing symptoms, the chance of death can be cut in half. “Every hour of delayed therapy increases mortality by 7 to 8 percent,” he says.

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New ‘tricorder’ technology might be able to ‘hear’ tumors

New ‘tricorder’ technology might be able to ‘hear’ tumors | Amazing Science | Scoop.it

Stanford electrical engineers have developed an enhancement of technology intended to safely find buried plastic explosives and spot fast-growing tumors, using a combination of microwaves and ultrasound to develop a detector similar to the legendary Star Trek tricorder.


The work, led by Assistant Professor Amin Arbabian and Research Professor Pierre Khuri-Yakub, grows out of DARPA research designed to detect buried plastic explosives, but the researchers said the technology could also provide a new way to detect early stage cancers.


The new work was spurred by a challenge posed by the Defense Advanced Research Projects Agency (DARPA), which sought a system to detect plastic explosives (improvised explosive devices or IEDs) buried underground, which are currently invisible to metal detectors. The detection device could not touch the surface in question, so as not to trigger an explosion.


The engineers developed a system based on the principle that all materials expand and contract when heated, but not at identical rates. In a potential battlefield application, the microwaves would heat the suspect area, causing the muddy ground to absorb energy and expand, and thus squeeze the plastic. Pulsing the microwaves would then generate a series of ultrasound pressure waves that could be detected and interpreted to disclose the presence of buried plastic explosives.


Sound waves propagate differently in solids than air, with a drastic transmission loss occurring when sound jumps from the solid to air. So the Stanford team accommodated for this loss by building highly sensitive capacitive micromachined ultrasonic transducers (CMUTs) that can specifically discern the weaker ultrasound signals that jumped from the solid, through the air, to the detector.


Solving the technical challenges of detecting ultrasound after it left the ground gave the Stanford researchers the experience to take aim at their ultimate goal: Using the device in medical applications without touching the skin.


Arbabian’s team used brief microwave pulses to heat a flesh-like material that had been implanted with a sample “target.” Holding the device at a standoff distance of 30 cm, the material was heated by a mere thousandth of a degree, well within safety limits. Yet even that slight heating caused the material to expand and contract, which, in turn, created ultrasound waves that the Stanford team was able to detect to disclose the location of the  4 square centimeter embedded target, all without touching the “flesh” — just like the Star Trek tricorder.


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Noninvasive imaging method can look twice as deep inside the living brain

Noninvasive imaging method can look twice as deep inside the living brain | Amazing Science | Scoop.it

University of Washington (UW) researchers have developed a noninvasive light-based imaging technology that can literally see inside the living brain at more than two times the depth, providing a new tool to study how diseases like dementia, Alzheimer’s, and brain tumors change brain tissue over time.


The work was reported Oct. 8 by Woo June Choi and Ruikang Wang of the UW Department of Bioengineering in the Journal of Biomedical Optics, published by SPIE, the international society for optics and photonics.


According to the authors, this new optical coherence tomography (OCT) approach to brain study may allow for examining acute and chronic morphological or functional vascular changes in the deep brain. OCT is normally used to obtain sub-surface images of biological tissue at about the same resolution as a low-power microscope and can instantly deliver cross-section images of layers of tissue without invasive surgery or ionizing radiation. OCT images are based on light directly reflected from a sub-surface.


Widely used in clinical ophthalmology, OCT has recently been adapted for brain imaging in small animal models. Its application in neuroscience has been limited, however, because conventional OCT technology hasn’t been able to image more than 1 millimeter below the surface of biological tissue.

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Injectable nanoparticles deliver cancer therapy in mice

Injectable nanoparticles deliver cancer therapy in mice | Amazing Science | Scoop.it

Researchers designed and tested a system that delivered nanometer-sized particles of a cancer drug to tumors in mice, improving survival.

 

Many drugs for treating cancer work by slowing or stopping the growth of cancerous cells. However, there are numerous barriers that can hinder a drug’s ability to work successfully. A drug needs to reach and get inside cancerous cells—whether they’re in the liver, breast, or lung. The drug must also avoid damaging healthy, non-cancerous tissues—such as the heart and kidneys—to prevent side effects.

 

A team led by Drs. Mauro Ferrari and Haifa Shen at Houston Methodist Research Institute has been working to overcome the many hurdles to successful cancer treatment by harnessing nanotechnology to deliver drugs directly into cancerous cells. The group set out to develop and test an injectable carrier of nanoparticles that contain a chemotherapy drug. The work was funded in part by NIH’s National Cancer Institute. Results were published on March 14, 2016, in Nature Biotechnology.

 

The scientists turned to doxorubicin (dox), a drug used to treat many cancer types. They attached dox to string-like molecules, known as poly(L-glutamic acid), through a pH-sensitive link. This formed a drug complex called pDox. The team made disk-shaped, micrometer-sized silicon particles to serve as a carrier for the pDox. The pDox was loaded into the particles through nanometer-sized pores.

 

When the researchers injected pDox-containing silicon particles intravenously into mice with cancerous tumors, the particles traveled through the blood stream and accumulated at the site of tumors, where blood vessels are leakier. The silicon, which was designed to degrade, released pDox molecules at the tumor site. These molecules spontaneously formed nanoparticles, which were then taken up by tumor cells.

 

Once inside cancerous cells, the pDox was transported to the area around the nucleus through vesicular transport. Due to the acidic environment near the nucleus, the dox was cleaved from its attachment to the poly(L-glutamic acid). This resulted in a high concentration of dox within the nuclei of the cancerous cells.

 

In contrast, when the researchers injected the drug dox alone, high levels appeared in non-cancerous tissues, such as the heart, leading to damage.

 

The team tested the therapy in several mouse cancer models, including triple-negative breast cancer, which is difficult to treat. Mice treated with the pDox-containing particles had much smaller and fewer tumors. They also had a longer survival time than mice given a saline control. The group found that 40-50% of cancer-bearing mice given the treatment showed no signs of metastatic tumors 8 months later. “We invented a method that actually makes the nanoparticles inside the cancer and releases the drug particles at the site of the cellular nucleus,” Ferrari says.

 

The silicon-based carrier could transport other chemicals, or combinations of chemicals, besides dox. The team plans to begin safety and efficacy studies in humans in the future.


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New 3D Printed Ovaries Allow Infertile Mice to Give Birth

New 3D Printed Ovaries Allow Infertile Mice to Give Birth | Amazing Science | Scoop.it

Northwestern University scientists created a prosthetic ovary using a 3D printer – an implant that allowed mice that had their ovaries surgically removed to bear live young. The results will be presented Saturday, April 2, at the Endocrine Society’s annual meeting, ENDO 2016, in Boston. Researchers hope to use the technology to develop an ovary bioprosthesis that could be implanted in women to restore fertility. One group that could benefit is survivors of childhood cancers, who have an increased risk of infertility as adults. An estimated 1 in 250 adults has survived childhood cancer.

 

“One of the biggest concerns for patients diagnosed with cancer is how the treatment may affect their fertility and hormone health,” said lead study author Monica M. Laronda, PhD, a postdoctoral research fellow at Northwestern University’s Feinberg School of Medicine. “We are developing new ways to restore their quality of life by engineering ovary bioprosthesis implants.”

 

The researchers used a 3D printer to create a scaffold to support hormone-producing cells and immature egg cells, called oocytes. The structure was made out of gelatin – a biological material derived from the animal protein collagen. The scientists applied biological principles to manufacture the scaffold, which needed to be rigid enough to be handled during surgery and to provide enough space for oocyte growth, blood vessel formation and ovulation.

 

Using human cell cultures, the researchers determined the optimal scaffold design should have crisscrossing struts that allowed the cells to anchor at multiple points. The scaffolds were seeded with ovarian follicles – the spherical unit that contains a centralized oocyte with surrounding supportive, hormone-producing cells – to create the bioprosthesis.

 

To test the implant, researchers removed the ovaries of mice and replaced them with the ovary bioprosthesis. Following the procedure, the mice ovulated, gave birth to healthy pups and were able to nurse.

 

Implanting the prosthetic ovary in mice also restored the estrous, or female hormone cycle. Researchers theorize a similar implant could help maintain hormone cycling in women who were born with or have undergone disease treatments that have reduced ovarian function. These women often experience decreased production of reproductive hormones that can cause issues with the onset of puberty as well as bone and vascular health problems later in life.

 

“We developed this implant with downstream human applications in mind, as it is made through a scalable 3D printing method, using a material already used in humans,” Laronda said. “We hope to one day restore fertility and hormone function in women who suffer from the side effects of cancer treatments or who were born with reduced ovarian function.”

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Human Term Placenta a New Abundant Source of Hematopoietic Stem Cells

Human Term Placenta a New Abundant Source of Hematopoietic Stem Cells | Amazing Science | Scoop.it

Investigators at Children’s Hospital Oakland Research Institute, Oakland, California found a way to obtain large numbers of hematopoietic stem cell from human term placenta. The results published in Experimental Biology and Medicine, give a detailed report on quantification, characterization, engraftment capacity, and most importantly, practical way to obtain hematopoietic stem cells from placenta in numbers that are several-fold higher than could be obtained from cord blood. The research team, Dr. Vladimir Serikov, MD, PhD, D.Sci, Assistant Staff Scientist, Catherine Hounshell, a research associate, Sandra Larkin, a research associate, Mr. William Green, student, Dr. Hirokazu Ikeda, MD, Visiting Scientist, Dr. Mark Walters, Medical Director of Children’s Hospital Oakland Hematology and Oncology Programs, and Dr. Frans Kuypers, Senior Scientist, performed studies in human term placentas, human cord blood, and immunodeficient mice.

 

Dr. Serikov said that the fact the human term placenta is a hematopoietic organ was reported by our team for the first time more than a year ago, and this year this finding was confirmed by UCSF scientists headed by Dr. S. Fisher. In this report, said Dr. Serikov, we demonstrate for the first time that human placentas could provide abundant amounts of CD34+ CD133+ colony-forming cells, as well as other primitive hematopoietic progenitors, suitable for transplantation in humans. The total amount of live hematopoietic stem cells, or colony-forming units in culture that could be obtained from placentas was an order of magnitude larger than the number of hematopoietic stem cells obtained from cord blood from the same source.

 

Hematopoietic stem cells which maintain their differentiation capacity, as well as stromal stem cells that support long-term culture of hematopoietic cells, can be harvested from perfusate of placenta following CXCR4 receptor blockade, said Dr. F. Kuypers. Importantly, live HPCs can similarly be obtained from whole cryopreserved placentas. Cells derived from placental tissue differentiated into all blood lineages in vitro. Animal experiments further demonstrated successful engraftment of placenta-derived HSC, which reconstituted hematopoiesis in immunodeficient mice.

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D-Eye: a smartphone-based retinal imaging system

D-Eye: a smartphone-based retinal imaging system | Amazing Science | Scoop.it

D-Eye, a smartphone-based retinal imaging system, has raised $1.68 million (1.5 euros) from Innogest, Invitalia Ventures, Giuseppe e Annamaria Cottino Foundation, and Si14. 

 

The product was first conceived in Padua, Italy, by Dr. Andrea Russo, an ophthalmologist, when he was examining his patients. D-Eye CEO Rick Sill told MobiHealthNews that Russo got the idea when he was with a patient one day and his phone rang.

 

“He looked at the smartphone and said ‘I wonder if it would be possible to use the smartphone as a digital ophthalmoscope because now I could actually capture images using the smartphone. Then I’d be able to transmit those images to other doctors to view if they were so interested,’” Sill explained in an interview. “He went out and bought himself a 3D printer and started cranking out ideas for attaching a lens on top of a smartphone that would allow him to do just that, to image the retina.”


Via Daniel Perez-Marcos
Dr. Stefan Gruenwald's insight:
Digital ophthalmoscope using smartphone: such a great way of expanding the use of everyday technology!
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Reid Johnson's curator insight, March 17, 10:47 AM
Digital ophthalmoscope using smartphone: such a great way of expanding the use of everyday technology!
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Digital ophthalmoscope using smartphone: such a great way of expanding the use of everyday technology!
Thirumurugan's curator insight, March 26, 5:09 AM
Digital ophthalmoscope using smartphone: such a great way of expanding the use of everyday technology!
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Scientists create painless patch of insulin-producing beta cells to control diabetes

Scientists create painless patch of insulin-producing beta cells to control diabetes | Amazing Science | Scoop.it

For decades, researchers have tried to duplicate the function of beta cells, which don't work properly in patients with diabetes. Now, researchers have devised another option: a synthetic patch filled with natural beta cells that can secrete doses of insulin to control blood sugar levels on demand.

 

Now, researchers at the University of North Carolina at Chapel Hill and North Carolina State University have devised another option: a synthetic patch filled with natural beta cells that can secrete doses of insulin to control blood sugar levels on demand with no risk of inducing hypoglycemia.

 

The proof-of-concept builds on an innovative technology, the "smart insulin patch," reported last year in the Proceedings of the National Academy of Sciences. Both patches are thin polymeric squares about the size of a quarter and covered in tiny needles, like a miniature bed of nails. But whereas the former approach filled these needles with manmade bubbles of insulin, this new "smart cell patch" integrates the needles with live beta cells.

 

Tests of this painless patch in small animal models of type-1 diabetes demonstrated that it could quickly respond to skyrocketing blood sugar levels and significantly lower them for 10 hours at a time. The results were published in Advanced Materials.

 

"This study provides a potential solution for the tough problem of rejection, which has long plagued studies on pancreatic cell transplants for diabetes," said senior author Zhen Gu, PhD, assistant professor in the joint UNC/NC State department of biomedical engineering. "Plus it demonstrates that we can build a bridge between the physiological signals within the body and these therapeutic cells outside the body to keep glucose levels under control."

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This 3D Printer Prints Bone, Cartilage, and Muscle

This 3D Printer Prints Bone, Cartilage, and Muscle | Amazing Science | Scoop.it

A team of biomedical researchers at Wake Forest Institute for Regenerative Medicine has just completed an invention 10 years in the making. It's a 3D printer that can craft relatively simple tissues like cartilage into large complex shapes—like an infant's ear. Using cartridges that are brimming with biodegradable plastic and human cells bound up in gel, this new kind of 3D printer builds complex chunks of growing muscle, cartilage, and even bone. When implanted into animals, these simple fabricated tissues survive and thrive indefinitely.


The scientists led by Anthony Atala surmounted two particularly thorny challenges that have long impeded the futuristic goal of printing living human tissues. First, their new device manufactures large, stable chunks of printed tissue that don't fall apart. Second, it keeps those large structures alive and growing. The new 3D printer is unveiled and outlined today in the journal Nature Biotechnology.


"This is the first bioprinter that can print tissue at the large scales relevant for human implantation,"  Atala says. "Basically, once we've printed a structure, we can keep it alive for several weeks before we implant it. Now the next step is to test these [printed tissues] for safety so we can implant them in the future in patients."


Atala's new device—named the Integrated Tissue and Organ Printing System, or ITOP—is straightforward. The programmed printer slowly squirts out layer upon layer of a rapidly hardening material in the form of tiny droplets. Like other 3D printers, this layered approach allows ITOP to print highly complex shapes in three dimensions with incredible detail. The materials ITOP uses, and the way it structures the tissues that it builds, are what make this machine revoutionary.

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No more insulin injections? Encapsulated pancreatic cells offer new possibilities

No more insulin injections? Encapsulated pancreatic cells offer new possibilities | Amazing Science | Scoop.it
Researchers have designed a material that prevents transplanted human islet cells from being attacked by the immune system in patients with Type 1 diabetes. The advance could help patients control their blood sugar without taking drugs.


Since the 1980s, a standard treatment for diabetic patients has been injections of insulin produced by genetically engineered bacteria. While effective, this type of treatment requires great effort by the patient and can generate large swings in blood sugar levels.


At the urging of JDRF director Julia Greenstein, Anderson, Langer, and colleagues set out several years ago to come up with a way to make encapsulated islet cell transplantation a viable therapeutic approach. They began by exploring chemical derivatives of alginate, a material originally isolated from brown algae. Alginate gels can be made to encapsulate cells without harming them, and also allow molecules such as sugar and proteins to move through, making it possible for cells inside to sense and respond to biological signals.


However, previous research has shown that when alginate capsules are implanted in primates and humans, scar tissue eventually builds up around the capsules, making the devices ineffective. The MIT/Children’s Hospital team decided to try to modify alginate to make it less likely to provoke this kind of immune response.


“We decided to take an approach where you cast a very wide net and see what you can catch,” says Arturo Vegas, a former MIT and Boston Children’s Hospital postdoc who is now an assistant professor at Boston University. Vegas is the first author of the Nature Biotechnology paper and co-first author of the Nature Medicine paper.


“We made all these derivatives of alginate by attaching different small molecules to the polymer chain, in hopes that these small molecule modifications would somehow give it the ability to prevent recognition by the immune system.”


After creating a library of nearly 800 alginate derivatives, the researchers performed several rounds of tests in mice and nonhuman primates. One of the best of those, known as triazole-thiomorpholine dioxide (TMTD), they decided to study further in tests of diabetic mice. They chose a strain of mice with a strong immune system and implanted human islet cells encapsulated in TMTD into a region of the abdominal cavity known as the intraperitoneal space.


The pancreatic islet cells used in this study were generated from human stem cells using a technique recently developed by Douglas Melton, a professor at Harvard University who is an author of the Nature Medicine paper. Following implantation, the cells immediately began producing insulin in response to blood sugar levels and were able to keep blood sugar under control for the length of the study, 174 days.


“The really exciting part of this was being able to show, in an immune-competent mouse, that when encapsulated these cells do survive for a long period of time, at least six months,” says Omid Veiseh, a senior postdoc at the Koch Institute and Boston Children’s hospital, co-first author of the Nature Medicine paper, and an author of the Nature Biotechnology paper. “The cells can sense glucose and secrete insulin in a controlled manner, alleviating the mice’s need for injected insulin.”

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New handheld miniature microscope could ID cancer cells in doctor’s offices and operating rooms

New handheld miniature microscope could ID cancer cells in doctor’s offices and operating rooms | Amazing Science | Scoop.it

A miniature handheld microscope being developed by University of Washington mechanical engineers could allow neurosurgeons to differentiate cancerous from normal brain tissue at cellular level in real time in the operating room and determine where to stop cutting.


The new technology is intended to solve a critical problem in brain surgery: to definitively distinguish between cancerous and normal brain cells, during an operation, neurosurgeons would have stop the operation and send tissue samples to a pathology lab — where they are typically frozen, sliced, stained, mounted on slides and investigated under a bulky microscope.


Developed in collaboration with Memorial Sloan Kettering Cancer Center, Stanford University and the Barrow Neurological Institute, the new microscope is outlined in an open-access paper published in January in the journalBiomedical Optics Express.


“Surgeons don’t have a very good way of knowing when they’re done cutting out a tumor,” said senior author Jonathan Liu, UW assistant professor of mechanical engineering. “They’re using their sense of sight, their sense of touch, and pre-operative images of the brain — and oftentimes it’s pretty subjective. “Being able to zoom and see at the cellular level during the surgery would really help them to accurately differentiate between tumor and normal tissues and improve patient outcomes.”


The handheld microscope, roughly the size of a pen, combines technologies in a novel way to deliver high-quality images at faster speeds than existing devices. Researchers expect to begin testing it as a cancer-screening tool in clinical settings next year.

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A microfluidic biochip for blood cell counts at the point-of-care

A microfluidic biochip for blood cell counts at the point-of-care | Amazing Science | Scoop.it
Teams of researchers from the University of Illinois at Urbana-Champaign (UIUC) have demonstrated a biosensor capable of counting the blood cells electrically using only a drop of blood. The blood cell count is among the most ubiquitous diagnostic tests in primary health care. The gold standard routinely used in hospitals and testing laboratories is a hematology analyzer, which is large and expensive equipment, and requires trained technicians and physical sample transportation. It slows turn-around time, limits throughput in hospitals, and limits accessibility in resource-limited settings. Bashir and his team have developed a biosensor to count red blood cell, platelet, and white blood cell counts, and its 3-part differential at the point-of-care while using only 11 microL of blood.

The microfluidic device can electrically count the different types of blood cells based on their size and membrane properties. To count leukocyte and its differentials, red blood cells are selectively lysed and the remaining white blood cells were individually counted. The specific cells like neutrophils were counted using multi-frequency analysis, which probe the membrane properties of the cells. However, for red blood cells and platelets, 1 microL of whole blood is diluted with PBS on-chip and the cells are counted electrically. The total time for measurement is under 20 minutes. The report appears in the December 2015 issue of the journal TECHNOLOGY.

"Our biosensor exhibits the potential to improve patient care in a spectrum of settings. One of the compelling is in resource-limited settings where laboratory tests are often inaccessible due to cost, poor prevalence of laboratory facilities, and the difficulty of follow-up upon receiving results that take days to process," says Professor Rashid Bashir of the University of Illinois at Urbana-Champaign and Principal Investigator on the paper.

There exists a huge potential to translate our biosensor commercially for blood cell counts applications," says Umer Hassan, Ph.D., the lead author on this paper. "The translation of our technology will result in minimal to no experience requirement for device operation. Even, patients can perform the test at the comfort of their home and share the results with their primary care physicians via electronic means too." "The technology is scalable and in future, we plan to apply it to many other potential applications in the areas of animal diagnostics, blood transfusion analysis, ER/ICU applications and blood cell counting for chemotherapy management" says Professor Bashir. The clinical trials of the biosensor are done in collaboration with Carle Foundation Hospital, Urbana, IL.
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New ultrasound technique for rapidly creating a 3D view of blood vessels in microscopic details

New ultrasound technique for rapidly creating a 3D view of blood vessels in microscopic details | Amazing Science | Scoop.it
Scientists use ultrasound to scan the blood vessels of an entire rat brain in microscopic 3D detail, pioneering a technique they say will improve cancer and stroke diagnosis.


They used it to scan the blood vessels throughout the brain of a live rat.

Within a few years, the researchers say their system could reach the clinic and help with cancer and stroke diagnosis. For the procedure, published in Nature, the rat was injected with millions of very tiny bubbles, which reflect sound waves much better than blood vessels.


"Ultrasound propagates easily in water - or in our organs, because almost 90% of our soft tissue is water," explained the study's senior author, Mickael Tanter, from the Institut Langevin in Paris. But as soon as it hits a very small microbubble of gas, there's a big reflection. It's a very good scatterer of ultrasound." This is what makes these bubbles, which are already used for some scans in humans, a "contrast agent" for ultrasound.


But the key to getting a sharp, super-resolution image - unlike conventional ultrasound, which is limited to capturing objects at millimeter scales - was to scan at a very high frame-rate. Instead of spending a long time acquiring a single, beautifully detailed image, the team snapped more than 500 coarse images every second and then compared them. The system they have built is able to compile those thousands of images and create a single, high-resolution view by looking at the differences between them - caused as the bubbles move around.


"We found a way to separate these bubbles by using ultrafast imaging," Prof Tanter explains. "If you take ultrafast images of the bubble cloud, and then you take one and you subtract the previous one, you see all the bubbles individually, time after time."


In two-and-a-half minutes he and his colleagues acquired enough images (75,000 to be precise) to compile a 3D view of the rat's brain with pixels just 10 micrometers (0.01mm) in size. "It makes a very, very nice map of the brain vasculature... even down to 2cm deep. You can see the whole brain, with microscopic resolution," Prof Tanter said.


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Google Glass helps cardiologists complete difficult coronary artery blockage surgery

Google Glass helps cardiologists complete difficult coronary artery blockage surgery | Amazing Science | Scoop.it

Cardiologists from the Institute of Cardiology, Warsaw, Poland have used Google Glass in a challenging surgical procedure, successfully clearing a blockage in the right coronary artery of a 49-year-old male patient and restoring blood flow, reports the Canadian Journal of Cardiology.


Chronic total occlusion, a complete blockage of the coronary artery, sometimes referred to as the “final frontier in interventional cardiology,” represents a major challenge for catheter-based percutaneous coronary intervention (PCI), according to the cardiologists.


That’s because of the difficulty of recanalizing (forming new blood vessels through an obstruction) combined with poor visualization of the occluded coronary arteries.


Coronary computed tomography angiography (CTA) is increasingly used to provide physicians with guidance when performing PCI for this procedure. The 3-D CTA data can be projected on monitors, but this technique is expensive and technically difficult, the cardiologists say.


So a team of physicists from the Interdisciplinary Centre for Mathematical and Computational Modelling of the University of Warsaw developed a way to use Google Glass to clearly visualize the distal coronary vessel and verify the direction of the guide-wire advancement relative to the course of the blocked vessel segment.


So a team of physicists from the Interdisciplinary Centre for Mathematical and Computational Modelling of the University of Warsaw developed a way to use Google Glass to clearly visualize the distal coronary vessel and verify the direction of the guide-wire advancement relative to the course of the blocked vessel segment.


The procedure was completed successfully, including implantation of two drug-eluting stents. “This case demonstrates the novel application of wearable devices for display of CTA data sets in the catheterization laboratory that can be used for better planning and guidance of interventional procedures, and provides proof of concept that wearable devices can improve operator comfort and procedure efficiency in interventional cardiology,” said lead investigator Maksymilian P. Opolski, MD, PhD, of the Department of Interventional Cardiology and Angiology at the Institute of Cardiology, Warsaw, Poland.


“We believe wearable computers have a great potential to optimize percutaneous revascularization, and thus favorably affect interventional cardiologists in their daily clinical activities,” he said. He also advised that “wearable devices might be potentially equipped with filter lenses that provide protection against X-radiation.

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How to control heartbeats more precisely, using light

How to control heartbeats more precisely, using light | Amazing Science | Scoop.it

Researchers from Oxford and Stony Brook universities has found a way to precisely control the electrical waves that regulate the rhythm of our heartbeat — using light. Their results are published in the journal Nature Photonics.


Cardiac cells in the heart and neurons in the brain communicate by electrical signals, and these messages of communication travel fast from cell to cell as “excitation waves.” For heart patients there are currently two options to keep these waves in check: electrical devices (pacemakers or defibrillators) or drugs (e.g., beta blockers). However, these methods are relatively crude: they can stop or start waves but cannot provide fine control over the wave speed and direction.


Gil Bub, from Oxford University explained: ‘When there is scar tissue in the heart or fibrosis, this can cause part of the wave to slow down. That can cause re-entrant waves which spiral back around the tissue, causing the heart to beat much too quickly, which can be fatal. If we can control these spirals, we could prevent that.


The solution the researchers found was optogenetics, which uses genetic modification to alter cells so that they can be activated by light. Until now, it has mainly been used to activate individual cells or to trigger excitation waves in tissue, especially in neuroscience research. “We wanted to use it to very precisely control the activity of millions of cells,” said Bub.


A light-activated protein called channelrhodopsin was delivered to heart cells using gene therapy techniques so that they could be controlled by light. Then, using a computer-controlled light projector, the team was able to control the speed of the cardiac waves, their direction and even the orientation of spirals in real time — something that never been shown for waves in a living system before.


In the short term, the ability to provide fine control means that researchers are able to carry out experiments at a level of detail previously only available using computer models. They can now compare those models to experiments with real cells, potentially improving our understanding of how the heart works. The research can also be applied to the physics of such waves in other processes. In the long run, it might be possible to develop precise treatments for heart conditions.


“Precise control of the direction, speed and shape of such excitation waves would mean unprecedented direct control of organ-level function, in the heart or brain, without having to focus on manipulating each cell individually,” said Stony Brook University scientist Emilia Entcheva.


The team stresses that there are significant hurdles before this could offer new treatments; a key issue is being able to alter the heart to be light-sensitized and being able to get the light to desired locations. However, as gene therapy moves into the clinic and with miniaturization of optical devices, use of this all-optical technology may become possible.

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