Approximately 14 percent of the world's population suffer from dry eye disease (DED) but treatments are limited because it's difficult to model the complex human eye for drug development. Now though, University of Pennsylvania bioengineers developed an "eye-on-a-chip" complete with a motorized blinking eyelid. The hope is that the artificial eye will lead to a deeper understanding of dry eye disease, enable drug screening, and even become a testbed for contact lens technology and eye surgery. Their technology also received the 2018 Lush Prize awarded for innovations that could help eliminate animal testing for shampoos and other beauty product. From Eurekalert:
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In this study, (Dan) Huh and (Jeongyun) Seo focused on engineering an eye model that could imitate a healthy eye and an eye with DED, allowing them to test an experimental drug without risk of human harm.
To construct their eye-on-a-chip, Huh's team starts with a porous scaffold engineered with 3D printing, about the size of a dime and the shape of a contact lens, on which they grow human eye cells. The cells of the cornea grow on the inner circle of scaffolding, dyed yellow, and the cells of the conjunctiva, the specialized tissue covering the white part of human eyes, grow on the surrounding red circle. A slab of gelatin acts as the eyelid, mechanically sliding over the eye at the same rate as human blinking. Fed by a tear duct, dyed blue, the eyelid spreads artificial tear secretions over the eye to form what is called a tear film.
More than 100 hours of MIR scanning has generated an image of a whole human brain with unprecedented level of detail. Massachusetts General Hospital researchers and their colleagues used a 7 Tesla MRI machine, recently approved by the FDA, to scan the donated brain from a 58-year-old-woman. The image shows detail down to .1 millimeter. From Science News:
Before the scan began, researchers built a custom spheroid case of urethane that held the brain still and allowed interfering air bubbles to escape. Sturdily encased, the brain then went into a powerful MRI machine called a 7 Tesla, or 7T, and stayed there for almost five days of scanning...
Researchers can’t get the same kind of resolution on brains of living people. For starters, people couldn’t tolerate a 100-hour scan. And even tiny movements, such as those that come from breathing and blood flow, would blur the images...
These (new kinds of) detailed brain images could hold clues for researchers trying to pinpoint hard-to-see brain abnormalities involved in disorders such as comas and psychiatric conditions such as depression.
"7 Tesla MRI of the ex vivo human brain at 100 micron resolution" (bioRxiv.org)
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In these two excellent short animations, data science professor Jeffrey Leek of the Simply Statistics blog and Johns Hopkins Bloomberg School of Public Health, and his university colleague, postdoctoral research Lucy McGowan, explain how "in medicine, there’s often a disconnect between news headlines and the scientific research they cover."
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The 1990s nanotechnology dream of tiny robots swimming through our blood stream to treat disease is moving (verrrry) slowly but surely toward reality. In a new milestone, researchers used an external magnetic field to steer microbots through a live mouse's body carrying therapeutic stem cells. From IEEE Spectrum:
..Delivering stem cells typically requires an injection with a needle, which lowers the survival rate of the stem cells, and limits their reach in the body. Microrobots, however, have the potential to deliver stem cells to precise, hard-to-reach areas, with less damage to surrounding tissue, and better survival rates, says Jin-young Kim, a principle investigator at DGIST-ETH Microrobotics Research Center, and an author on the paper....
The team fabricated the robots with 3D laser lithography, and designed them in two shapes: spherical and helical. Using a rotating magnetic field, the scientists navigated the spherical-shaped bots with a rolling motion, and the helical bots with a corkscrew motion. These styles of locomotion proved more efficient than that from a simple pulling force, and were more suitable for use in biological fluids, the scientists reported....
Kim says he and his colleagues are developing imaging systems that will enable them to view in real time the locomotion of their microrobots in live animals.
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In a recent scientific study on overactive urinary bladder syndrome, researchers used the term "latchkey incontinence" to describe "the loss of urine that occurs when one arrives home and puts the key in the lock of one’s front door." From MEL Magazine:
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According to Jamin Brahmbhatt, a urologist in Florida, peeing is a much more complex dance between the mind and body than you might think. “The ability to control how you urinate requires a balance between the muscles and your nerves around your bladder and your urethra working in synch,” he explains. “Some of these functions happen automatically, and some require manual control by the muscles that you naturally control. So when urine is filling up inside your bladder, your bladder naturally expands. When you go to the bathroom, your sphincter around your urethra will relax and your bladder will start to squeeze. This process sounds simple, but it does require the muscles around your urethra, which we call your pelvic floor, to all work and synch.”
He continues, “To keep your bladder healthy, I recommend my patients empty their bladder before they start having extreme ‘got-to-go’ feelings. There’s only so much the bladder can tolerate, and this process gets more complicated with the presence of a prostate, which naturally grows as men get older. All these processes can also be affected by diabetes, strokes, infections and many other medical problems.”
The RaniPill is another syringe that you can swallow to deliver drugs to the bloodstream from the inside. It's triggered by an interesting and complex mechanism involving a chemical reaction that inflates a tiny polymer balloon to push the needle into the intestinal wall. Rani Therapeutics just completed a successful 20-person trial using a pill that shoots blanks. From IEEE Spectrum:
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Working from the outside in, the RaniPill consists of a special coating that protects the pill from the stomach’s acidic juices. Then, as the pill is pushed into the intestines and pH levels rise to about 6.5, the coating dissolves to reveal a deflated biocompatible polymer balloon.
Upon exposure to the intestinal environment, a tiny pinch point made of sugar inside the balloon dissolves, causing two chemicals trapped on either side of the pinch point to mix and produce carbon dioxide. That gas inflates the balloon, and the pressure of the inflating balloon pushes a dissolvable microneedle filled with a drug of choice into the wall of the intestines. Human intestines lack sharp pain receptors, so the micro-shot is painless.
The intestinal wall does, however, have lots and lots of blood vessels, so the drug is quickly taken up into the bloodstream, according to the company’s animal studies. The needle itself dissolves...
Participants passed the remnants of the balloon within 1-4 days.
(Founder Mir) Imran calls the device a robot though it has no electrical parts and no metal. “Even though it has no brains and no electronics, it [works through] an interplay between material science and the chemistry of the body,” says Imran.
Semi-identical twins -- a boy and girl who are identical on their mother's side but share only 78% of their father's genome -- have been identified in Brisbane, Australia. This is only the second known case, ever. From the BBC:
"The mother's ultrasound at six weeks showed a single placenta and positioning of amniotic sacs that indicated she was expecting identical twins," (said Prof Nicholas Fisk whose team at the Royal Brisbane and Women's Hospita cared for the children when they were born in 2014).
"However, an ultrasound at 14 weeks showed the twins were male and female, which is not possible for identical twins."
If one egg is fertilised by two sperm, it results in three sets of chromosomes, rather than the standard two - one from the mother and two from the father.
And, according to researchers, three sets of chromosomes are "typically incompatible with life and embryos do not usually survive".
The identity of the twins has not been revealed.
A scientific paper about these rare humans was published the New England Journal of Medicine: "Molecular Support for Heterogonesis Resulting in Sesquizygotic Twinning"
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Biomedical engineers prototyped a pill that integrates a syringe to inject insulin into the floor of the stomach. From Science News:
The shape is designed to guide the device to rest, cap down, on the floor of the stomach. There, it sticks a needle tip composed almost entirely of insulin a few millimeters into the mucus membrane lining the stomach. Once the insulin needle tip dissolves, the device passes through the rest of the digestive system.
Thanks to the dearth of sharp pain receptors inside the stomach, the tiny injection “is unlikely to cause any discomfort,” says study coauthor Giovanni Traverso, a gastroenterologist and biomedical engineer at Brigham and Women’s Hospital in Boston and MIT.
"An ingestible self-orienting system for oral delivery of macromolecules" (Science) Read the rest
Smart toilets that analyze urine and poop in the bowl have been demonstrated for years, but now Rochester Institute of Technology engineers have integrated multiple kinds of biosensors into the toilet's seat. The WiFi-enable systems tracks EEG, blood oxygen levels, and the heart's pumping force. From IEEE Spectrum:
If the monitoring system works as expected, the device could help catch early signs of heart decline and decrease the number of hospitalizations for heart patients.
To test their seat, the team gathered blood pressure and blood oxygenation measurements from 18 volunteers in a laboratory who were instructed to sit on the seat but not urinate, defecate, or talk. Urination and defecation can shift readings since they put minor stress on the body, says Conn. While the system currently operates with algorithms that analyze signal quality, in the future Conn also plans to incorporate algorithms to identify and reject those inevitable bathroom moments from the data set.
But even if a person is fidgety on the toilet and the system fails to record a clean signal, there is always the next time. “If you’re not going to pick it up in the morning, you might pick it up at night. People are going to continuously use this seat,” says (researcher Nicholas) Conn.
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Fertility doctors often advise men that wearing boxers instead of briefs lowers scrotal temperature and possibly increase sperm count. The CoolMen device takes that idea to the extreme, instrumenting the wearer's testicles with temperature, pulse, and motion sensors while also cupping them in a specific position conducive to coolness. From the Polish start-up CoolTec:
CoolMen is an innovative device that stabilizes the temperature of the testicles in the optimum range. In a short time, CoolMen significantly improves semen parameters, contributing to increased fertility of the pair.
CoolMen can record data about temperature and time of use as well as types of activity (sleep, sitting, physical activity) by wirelessly transferring it to the mobile application on the smartphone. These data can then be analyzed by the andrologist to improve the treatment process...
CoolMen has been designed to be completely invisible under clothing, providing full discretion during use.
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OK, it's not quite Dr. Crusher's dermal regenerator (seen above), but Arizona State University researchers have demonstrated a laser system for sealing wounds. The system involves a sealing paste -- made from silk protein mixed with gold nanorods -- that bonds with skin when heated with a laser. From IEEE Spectrum:
To use a laser to seal skin, one must focus the heat of the light using some sort of photoconverter. (Chemical engineer Caushal) Rege’s lab opted for gold nanorods and embedded them in a silk protein matrix purified from silkworm cocoons. A silk protein called fibroin binds to collagen, the structural protein that holds together human skin cells. When near-infrared light hits the gold nanorods, they produce heat and activate the silk and skin to create bonds, forming a sturdy seal...
They are currently watching how the laser-activated seals hold up in living rats. If that goes well, they’ll move to pigs, and perhaps eventually, humans.
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Researchers have spent decades exploring methods to 3D print organs for transplant but progress is slow due to the complex structure of, say, a kidney or pancreas. Precise Bio, a startup founded by scientists from Wake Forest Institute for Regenerative Medicine, claim that the first real success will come from 3D-printed corneas. They've already conducted animal studies and are building a roadmap toward human trials. From IEEE Spectrum
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Corneas could be the first mainstream application of bioprinting, (Precise Bio CEO Aryeh) Batt says, in part because they have a layered structure that’s a good match for the technology. Each layer consists of different types of cells and fibers, which the printer could lay down in sequence, and these layers don’t contain blood vessels or nerves. What’s more, putting a new kind of transplant in the eye is inherently safer than implanting one deep in the body, since physicians could easily check for signs of trouble and could remove the tissue if anything seemed wrong.
There’s certainly a need for more corneas in the world, says Kevin Corcoran, president and CEO of the Eye Bank Association of America. In 2017, his members supplied nearly 51,000 transplantable corneas to patients in the United States, and also sent more than 26,000 abroad. Internationally, “there is a tremendous amount of unmet demand,” he says. “It’s estimated that 10 million people suffer from corneal blindness globally, primarily because they lack access to effective and affordable treatment.”
Part of Precise Bio’s proprietary approach is its printer, which uses a technique called laser-induced forward transfer to propel droplets of bioinks onto a surface.
Currently undergoing clinical trials, the Vibrant capsule is a tiny vibrator inside a capsule that you swallow to relieve constipation. Don't worry though because according to the web site, "the capsule is controlled by an algorithm." Whew. From Vibrant Ltd:
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Constipation relief is achieved by the capsule’s vibrations on the large intestinal wall, consequently inducing natural peristaltic activity, generating additional spontaneous bowel movements.
The capsule is activated by a base unit that transfers the data to the capsule.
The capsule operates inside the large intestine and is washed out of the body with the bowel movement. It meets the highest safety standards, using biocompatible materials.
Xavier Cunningham, age 10 of Kansas City, Kansas, was climbing up to a tree house when yellow jackets attacked. Cunningham fell several feet from the ladder and impaled his head on a meat skewer. University of Kansas surgeons removed the skewer during a several hour operation. Cunningham is doing quite well and expected to be released in a few days. From Fox4KC
"He was more upset about the yellow jackets than he was about the metal piece sticking out of his face," (Cunnigham's dad Shannon) Miller said.
"It missed his brain. It missed his brain stem. It missed the nerves, everything that`s valuable in your head. It missed everything," Xavier's dad said...
"Only God could have directed things to happen in a way that would save him like this," he said. "It really was a miracle."
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Neurologist Steven Laureys is an expert on the mysteries of consciousness. A researcher and clinician at the Belgian National Fund of Scientific Research he's known for testing comatose patients for any hidden signs of consciousness. From Scientific American's interview with Laureys:
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So how is it possible to study something as complex as consciousness?
There are a number of ways to go about it, and the technology we have at our disposal is crucial in this regard. For example, without brain scanners we would know much, much less than we now do. We study the damaged brains of people who have at least partially lost consciousness. We examine what happens during deep sleep, when people temporarily lose consciousness. We’ve also been working with Buddhist monks because we know that meditation can trigger alterations in the brain; connections that are important in the networks involved in consciousness show changes in activity. Hypnosis and anesthesia can also teach us a great deal about consciousness. In Lige, surgeons routinely operate on patients under hypnosis ( including Queen Fabiola of Belgium). Just as under anesthesia, the connections between certain brain areas are less active under hypnosis. And finally, we are curious to understand what near-death experiences can tell us about consciousness. What does it mean that some people feel they are leaving their bodies, whereas others suddenly feel elated?
Patients are brought to Lige from all over Europe to undergo testing. How do you determine whether they are conscious?
Well, of course, the physician will say, “Squeeze my hand”—but this time while the patient is in a brain scanner.
Over five days, a 32-year-old woman in Russia took selfies to document a strange lump on her face that moved from under her left eye to above it and then later to her lip. She finally visited a physician who reported a "superficial moving oblong nodule at the left upper eyelid." Turns out, she had a particular kind of parasitic worm, Dirofilaria repens
, living under her skin. From Live Science
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Humans are "accidental" hosts — in other words, not where the worms want to end up — and once a worm gets into a human, it typically can't reproduce.
The worms are spread by mosquito bites, and human cases have been reported in parts of Europe, Asia and Africa, the 2011 report said. The Russian woman said she had recently traveled to a rural area outside Moscow and was frequently bitten by mosquitoes, according to the new report (in the New England Journal of Medicine)...
The Russian woman had the worm removed and made a full recovery, the report said.