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Flying Through Auroras: Airline Carries Passengers into Southern Lights


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Flying Through Auroras: Airline Carries Passengers into Southern Lights

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This Heart in a Jar Could Make Heart Transplants Safer


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This Heart in a Jar Could Make Heart Transplants Safer

3/11/16 3:59pm

What looks like a prop from a steampunk movie is actually a partially decellularized heart in a bioreactor. And this heart has the potential to save the lives of heart attack patients, and, one day, people who need heart transplants too.

In a new paper in Circulation Research, scientists at Massachusetts General Hospital describe a process that was first tested on rat hearts and those of large mammals, and is now being applied to human organs. The process involves stripping away the muscle cells in the heart, leaving the rest of the structures intact, and then rebuilding the heart with new muscle cells. That sounds redundant, but it could provide people with “patches” that replace damaged tissue, and save heart transplant patients from rejecting their new organs.

The process starts with hearts from organ donors. A special detergent strips away the muscle cells, but leaves the proteins and blood vessels. This decellularization gets rid of not just muscle cells, but also of human leukocyte antigens (HLAs). HLAs are the proteins that the body uses to know which cells to sic the immune system on. They’re passed down from parents to children, which is why siblings are the best possible donors for patients in need of kidneys or livers. The wrong HLA markers will cause a patient to reject organs. Stripping the HLAs will help transplant patients accept foreign tissue.

But before that happens, the team has to rebuild the tissue. They started with pluripotent stem cells, which they induced into forming cardiac muscle cells. The cardiac cells were grown in a tissue culture for several days, and then injected into the decellularized hearts. The hearts were put in a bioreactor—a device that supplies nutrients to the cells and sometimes gently moves the organs to encourage cell growth. After two weeks, the team found cardiac cells that, through immature, could contract like regular cardiac muscle tissue.

Recreating an entire human heart is still a few years away. The immediate next step are “myocardial patches” that will allow people who have suffered heart attacks to replaced badly damaged muscle tissue—without worrying about rejection.

[Circulation Research]

The World’s Smallest Pacemaker Can Be Implanted Without Surgery


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The World’s Smallest Pacemaker Can Be Implanted Without Surgery

4/07/16 1:03pm

Image: Medtronic

The U.S. Food and Drug Administration has approved an injectable pacemaker that doesn’t require wired leads, which often lead to complications.

Image: Medtronic

The one-inch long Medtronic-built device, called the Micra Transcatheter Pacing System, is about a tenth the size of traditional pacemakers—making it the smallest in the world.

It’s intended for patients with atrial fibrillation (an irregular or rapid heart rate) and other dangerous arrhythmias, including bradycardia-tachycardia syndrome. The FDA approved the device in light of a Medtronic clinical trial involving 719 patients who were implanted with the device. After six months, around 98 percent of the patients experienced adequate heart pacing. A small fraction (7 percent) of patients experienced major complications, such as cardiac injuries, device dislocation, and blood clots.

Conventional pacemakers, which are surgically implanted, require wired leads that run from the pacemaker to an implant located just below the collarbone. These leads run through a vein directly into the heart’s right ventricle, delivering electrical impulses to treat irregular or stalled heart beats. The problem with these wires, aside from the clunkiness of it all, is that they sometimes malfunction. They can also cause problems when infections develop in the surrounding tissue, requiring a surgical procedure to replace the pacemaker.

Image: Medtronic

Micra doesn’t use wired leads at all. The device latches onto the heart using small hooks, where it delivers electrical pulses that keep the heart beating more regularly. The device is implanted through a thin 41-inch-long (105 cm) tube inserted into a vein in the patient’s groin. It travels through the vein, making its way to the heart’s right ventricle. Micra only paces the lower chamber of the heart, so it can’t be used for patients who need pacing in both the upper and lower chamber.

“As the first leadless pacemaker, Micra offers a new option for patients considering a single chamber pacemaker device, which may help prevent problems associated with the wired leads,” noted the FDA’s William Maisel in a press statement.

The FDA said it shouldn’t be used for patients who already have implanted devices, as they could interfere with pacemaker function. It also can’t be used for people who are severely obese, or who are intolerant to materials in the device or the blood thinner heparin.

[FDA, Medtronic]

George is a contributing editor at Gizmodo and io9.

Scientists Demonstrate Method of Turning Spinach Leaves Into Human Heart Tissue


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Scientists Demonstrate Method of Turning Spinach Leaves Into Human Heart Tissue 

Today 12:59pm

GIF: WPI

Spinach has long been understood to be good for your heart. But researchers have demonstrated that some day spinach could actually be your heart. Specifically, it could be used to repair damaged tissue by giving human heart tissue a plant-infused vascular system.

Scientists have previously fabricated human tissue with 3D printing, but the tiny blood vessels have proven to be a more difficult prospect for duplication. A team of researchers from several American universities has gone back to nature to solve that problem and their results are extremely encouraging.

Spinach leaves have fine veins that transport water and nutrients to the plant’s cells. The process that’s outlined in a new paper published inBiomaterials shows that the plant cells can be removed, leaving behind only the cellulose structure that keeps those cells in place.

The authors of the study write:

Cellulose, which is the most abundant component of plant cell walls, is a well-studied biomaterial for a variety of clinical applications. Cellulose is biocompatible and has been shown to promote wound healing. Furthermore, cellulosic tissue engineering scaffolds derived from decellularized apple slices have shown the ability for mammalian cell attachment and proliferation and were found to be biocompatible when implanted subcutaneously in vivo.

From there, they were able to seed live human cells onto the spinach scaffolding. Once the human tissue had grown around the network of veins, they were able to show that blood cells could flow through the system by pumping fluids and microbeads into it.

For patients with damage to their cardiac muscle tissue, this could be a game changer. New heart matter could be generated by using the altered plant veins as replacement blood vessels to deliver oxygen to the tissue.

We’re not nearly to the point that this could be implemented in surgery but the authors of the paper believe that it’s a viable first step towards “a new branch of science that investigates the mimicry between kingdoms, e.g. between plant and animal.”

I, for one, welcome a future in which I become part-plant, part-human.

[Biomaterials via National Geographic]

Peer Into the Guts of a Monster Tornado With This Incredible Simulation


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 Peer Into the Guts of a Monster Tornado With This Incredible Simulation

Credit: UW-Madison

Using a powerful supercomputer, meteorologists have simulated the “El Reno” tornado—a category 5 storm that swept through Oklahoma on May 24, 2011.

A research team led by Leigh Orf from the University of Wisconsin-Madison’s Cooperative Institute for Meteorological Satellite Studies (CIMSS) has used a high-efficiency supercomputer to visualize the inner workings of tornados and the powerful supercells that produce them. As part of the project, the researchers recreated a tornado-producing supercell that devastated the Great Plains six years ago. Their new models are providing fresh insights into these monstrous storms and how they form.

During a four-day stretch in late May 2011, several tornadoes touched down over the Oklahoma landscape. One of these storms, dubbed “El Reno,” registered as an EF-5—the strongest category on the Enhanced Fujita scale. This beast of a tornado touched down near Hinton, Oklahoma, where it proceeded to blaze a trail of destruction for nearly two hours. By the time it was over, the storm caused extensive damage along a 63-mile (101 km) long path, killing nine people and injuring 161 others.

To simulate the incredibly complex set of meteorological factors required to produce this particular tornado, Orf’s team was given access to the Blue Waters Supercomputer, located at the National Center for Supercomputing Applications at the University of Illinois at Urbana-Champaign.

Orf’s team used real-world observational data to recreate the conditions at the time of the storm, including a vertical profile of temperature, air pressure, wind speed, and moisture. Together, these ingredients contribute to “tornadogenesis”—the conditions required for a supercell to spawn a tornado.

Unlike a conventional computer program, where code is written to churn out predictable results, the researchers sought to create a “true” representation by feeding archived weather data into software that simulates weather. This provided a degree of variability that’s reflective of how weather works in nature; no two storms are exactly alike. In total, it took the machine more than three days to compile the tornado—a task that would have taken decades for a conventional desktop computer.

Once the main tunnel forms, several “mini” tornadoes form alongside it. They eventually merge, making the tornado even stronger. (Credit: UW-Madison)

Looking at the simulation, the researchers observed numerous “mini tornadoes” that formed at the onset of the main tornado. As the main funnel cloud took shape, the smaller tornadoes began to merge, adding strength to the superstructure and boosting wind speeds.

The simulation revealed several structures that make up a fully-formed tornado, including the streamwise vorticity current (SVC), thought to be a main driver of the tornadic activity (seen in yellow). (Image: University of UW-Madison)

Eventually, a new structure known as the streamwise vorticity current (SVC) formed within the tornado. “The SVC is made up of rain-cooled air that is sucked into the updraft that drives the whole system,” said Orf in a statement. “It’s believed that this is a crucial part in maintaining the unusually strong storm, but interestingly, the SVC never makes contact with the tornado. Rather, it flows up and around it.”

From here, Orf would like to share his team’s data with scientists and meteorologists across the United States. “We’ve completed the EF-5 simulation, but we don’t plan to stop there,” says Orf. “We are going to keep refining the model and continue to analyze the results to better understand these dangerous and powerful systems.”

[University of Wisconsin-Madison]

These 3 Superbugs Pose the Greatest Threat to Human Health


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These 3 Superbugs Pose the Greatest Threat to Human Health

The Most Interesting Science News Articles of the Week


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The Most Interesting Science News Articles of the Week