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Notable Moments in Limb and Face Transplant History

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In 2008, surgeons completed two procedures that could forever change transplant surgery. In August, doctors in Munich announced that a farmer was recovering from a double-arm transplant—the first double-arm transplant in the world. In December, the Cleveland Clinic announced they'd replaced about 80 percent of a woman's face. Many surgeons think that arm, hand, and face replacements are the next logical steps in transplants. Is the world ready?

Being first isn't always best

In 1964, physicians around the world were attempting transplants of all kinds when doctors in Ecuador performed the first hand transplant. Unfortunately, like early organ transplants, it didn't work—within two weeks the hand was rejected and doctors had to remove it.

Being second isn't much better

In 1998, doctors performed delicate microsurgery on New Zealander Clint Hallam. For 13 hours at Edouard Herriot Hospital, an international team of scientists led by French surgeon Jean Michel Dubernard stitched a cadaver's forearm and hand to Hallam's upper arm. Completing the hand transplant required microsurgery skills and patience—doctors knitted medial nerve to medial nerve, radial artery to radial artery, radius to radius. Like with other transplants, both donor and recipient must share the same blood type.

After years of studying transplant pioneers and earning a PhD based in xenographs research (he transplanted organs from one species of monkeys to another), Dubernard felt he was prepared to perform a hand transplant on a human. When he was unable to find a suitable French candidate, an Australian colleague recommended Hallam. Fourteen years earlier, Hallam had lost his forearm in a circular saw accident. It was later revealed the accident actually occurred in jail and that Hallam was a longtime con-man.

hands.jpgCritics claimed that Dubernard performed the surgery for the media attention, but the surgeon argued he and his staff did a thorough psychological evaluation of Hallam as well as a background check. (Unsurprisingly, Dubernard had a role in the first partial face transplant, also surrounded by controversy.)


At first, the forearm and hand worked well for Hallam, although he hated that the donor limb was larger than his other arm and a different skin tone. He hid his freak arm as much as he could. Hallam's arm wasn't just grotesque-looking, though; it began itching and flaking, and he was plagued daily by pins and needles. He begged the doctors to remove it, but they refused. Hallam felt emotionally detached from his hand. Finally, a group of British surgeons agreed to remove the limb in 2001. The physicians from France claimed the only reason Hallam's arm rejected is because he failed to take his immunosuppressant drugs and exercise it.

From hands to a face

Frenchwoman Isabella Dinore received the first partial face transplant in 2005.

After taking too many sleeping pills, Dinore had passed out. As she lay unconscious on the floor, her black Lab chewed off her nose, mouth, and lower face. Without lips, muscles, and skin on the bottom half of her jaw, Dinore struggled to speak and eat—she had to eat through a tube. Physicians couldn't help her with traditional plastic surgery and thus felt she would be a good candidate for a face transplant.

Bernard Devauchelle, a French maxillofacial surgeon at Lyon University, saw a picture of a brain-dead woman with a mouth, nose, and lips similar to Dinore's features. He removed a triangle of Maryline St. Aubert's skin with its arteries, nerves, and veins and spent hours graphing the skin onto Dinore's face.

Dinore.jpgIt was rumored St. Aubert was brain-dead because she tried to kill herself. Many people thought Dinore had attempted suicide, too. Dubernard, who had worked alongside Devauchelle in the surgery, argued Dinore accidentally overdosed. Physicians criticized the decision to give a suicidal woman a face transplant. People once again alleged Dubernard had performed the surgery for media attention—Corbis had an exclusive deal for photos—and some urged an ethics investigation.

Dubernard oversaw Dinore's recovery. Shortly after the surgery, he injected some of St. Aubert's stem cells (from her bone marrow) into Dinore in the hopes her body wouldn't reject the transplant, but the stem cell infusion failed. Dinore suffered two bouts of rejection, contracted herpes and a pox virus, and struggled with kidney failure.

A year later, Dinore appeared in the media, showing off her new face. She used her new lips to smoke again.

Full-face transplant

Coler.jpgLaurent Lantieri, head of plastic surgery at Henri-Mondor Hospital in France, spent 16 hours stitching new lips, cheeks, nose, and mouth to Pascal Coler's face. Since Coler was six years old, large masses had been growing on his nerves because of a condition called neurofibromatosis. As the masses increased in size, Coler's face became less recognizable. Strangers pointed at him because of his misshapen visage.


The large masses compressed the nerves, arteries, and fat in Coler's face, causing lasting damage; the transplanted cadaver's face stops the masses from developing. Lantieri didn't alter Coler's bone structure, so Coler looks as he would if he never had the disease.

What the doctors say

When a patient receives a lung or a liver, the body's white blood cells attack the new organ because the body believes it is an invader. That's why immunosuppressant drugs are so important for transplant patients: immunosuppressants mollify the immune system. When a transplant includes so many different tissues, organs, veins, arteries, nerves, fat, and bones, the body targets the limb even more ferociously than it attacks one organ—the white blood cells believe the more transplanted tissue means there are more invaders.

In 2007, a study was published with the results of 18 transplants of 24 hands/digits/forearms. (11 folks received one hand, four received two hands, two received two forearms, and one received one thumb.) The good news: limb transplantation has a 100 percent survival rate. (In the early days of organ transplantation, most patients died.) And graph survival is also 100 percent for the first two years. The bad news: 12 patients suffered acute rejection and six Chinese recipients had their hands removed. All patients had enough nerve function in their new limbs that they knew when they were hurt, but few used fine motor skills or had sophisticated nerve function.

Some experts wonder if limb transplants should be conducted when prosthetic limbs are available. Fifteen people in the 2007 study said the limbs improved their quality of life, but many suffer with lingering problems from the immunosuppressant drugs, kidney failure, diabetes, and infections.

One thing is certain, though: Dubernard won't be performing any more limb transplants. He reached the maximum age to practice medicine in France.

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iStock // Ekaterina Minaeva
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technology
Man Buys Two Metric Tons of LEGO Bricks; Sorts Them Via Machine Learning
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iStock // Ekaterina Minaeva

Jacques Mattheij made a small, but awesome, mistake. He went on eBay one evening and bid on a bunch of bulk LEGO brick auctions, then went to sleep. Upon waking, he discovered that he was the high bidder on many, and was now the proud owner of two tons of LEGO bricks. (This is about 4400 pounds.) He wrote, "[L]esson 1: if you win almost all bids you are bidding too high."

Mattheij had noticed that bulk, unsorted bricks sell for something like €10/kilogram, whereas sets are roughly €40/kg and rare parts go for up to €100/kg. Much of the value of the bricks is in their sorting. If he could reduce the entropy of these bins of unsorted bricks, he could make a tidy profit. While many people do this work by hand, the problem is enormous—just the kind of challenge for a computer. Mattheij writes:

There are 38000+ shapes and there are 100+ possible shades of color (you can roughly tell how old someone is by asking them what lego colors they remember from their youth).

In the following months, Mattheij built a proof-of-concept sorting system using, of course, LEGO. He broke the problem down into a series of sub-problems (including "feeding LEGO reliably from a hopper is surprisingly hard," one of those facts of nature that will stymie even the best system design). After tinkering with the prototype at length, he expanded the system to a surprisingly complex system of conveyer belts (powered by a home treadmill), various pieces of cabinetry, and "copious quantities of crazy glue."

Here's a video showing the current system running at low speed:

The key part of the system was running the bricks past a camera paired with a computer running a neural net-based image classifier. That allows the computer (when sufficiently trained on brick images) to recognize bricks and thus categorize them by color, shape, or other parameters. Remember that as bricks pass by, they can be in any orientation, can be dirty, can even be stuck to other pieces. So having a flexible software system is key to recognizing—in a fraction of a second—what a given brick is, in order to sort it out. When a match is found, a jet of compressed air pops the piece off the conveyer belt and into a waiting bin.

After much experimentation, Mattheij rewrote the software (several times in fact) to accomplish a variety of basic tasks. At its core, the system takes images from a webcam and feeds them to a neural network to do the classification. Of course, the neural net needs to be "trained" by showing it lots of images, and telling it what those images represent. Mattheij's breakthrough was allowing the machine to effectively train itself, with guidance: Running pieces through allows the system to take its own photos, make a guess, and build on that guess. As long as Mattheij corrects the incorrect guesses, he ends up with a decent (and self-reinforcing) corpus of training data. As the machine continues running, it can rack up more training, allowing it to recognize a broad variety of pieces on the fly.

Here's another video, focusing on how the pieces move on conveyer belts (running at slow speed so puny humans can follow). You can also see the air jets in action:

In an email interview, Mattheij told Mental Floss that the system currently sorts LEGO bricks into more than 50 categories. It can also be run in a color-sorting mode to bin the parts across 12 color groups. (Thus at present you'd likely do a two-pass sort on the bricks: once for shape, then a separate pass for color.) He continues to refine the system, with a focus on making its recognition abilities faster. At some point down the line, he plans to make the software portion open source. You're on your own as far as building conveyer belts, bins, and so forth.

Check out Mattheij's writeup in two parts for more information. It starts with an overview of the story, followed up with a deep dive on the software. He's also tweeting about the project (among other things). And if you look around a bit, you'll find bulk LEGO brick auctions online—it's definitely a thing!

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iStock
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Live Smarter
Working Nights Could Keep Your Body from Healing
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iStock

The world we know today relies on millions of people getting up at sundown to go put in a shift on the highway, at the factory, or in the hospital. But the human body was not designed for nocturnal living. Scientists writing in the journal Occupational & Environmental Medicine say working nights could even prevent our bodies from healing damaged DNA.

It’s not as though anybody’s arguing that working in the dark and sleeping during the day is good for us. Previous studies have linked night work and rotating shifts to increased risks for heart disease, diabetes, weight gain, and car accidents. In 2007, the World Health Organization declared night work “probably or possibly carcinogenic.”

So while we know that flipping our natural sleep/wake schedule on its head can be harmful, we don’t completely know why. Some scientists, including the authors of the current paper, think hormones have something to do with it. They’ve been exploring the physiological effects of shift work on the body for years.

For one previous study, they measured workers’ levels of 8-OH-dG, which is a chemical byproduct of the DNA repair process. (All day long, we bruise and ding our DNA. At night, it should fix itself.) They found that people who slept at night had higher levels of 8-OH-dG in their urine than day sleepers, which suggests that their bodies were healing more damage.

The researchers wondered if the differing 8-OH-dG levels could be somehow related to the hormone melatonin, which helps regulate our body clocks. They went back to the archived urine from the first study and identified 50 workers whose melatonin levels differed drastically between night-sleeping and day-sleeping days. They then tested those workers’ samples for 8-OH-dG.

The difference between the two sleeping periods was dramatic. During sleep on the day before working a night shift, workers produced only 20 percent as much 8-OH-dG as they did when sleeping at night.

"This likely reflects a reduced capacity to repair oxidative DNA damage due to insufficient levels of melatonin,” the authors write, “and may result in cells harbouring higher levels of DNA damage."

DNA damage is considered one of the most fundamental causes of cancer.

Lead author Parveen Bhatti says it’s possible that taking melatonin supplements could help, but it’s still too soon to tell. This was a very small study, the participants were all white, and the researchers didn't control for lifestyle-related variables like what the workers ate.

“In the meantime,” Bhatti told Mental Floss, “shift workers should remain vigilant about following current health guidelines, such as not smoking, eating a balanced diet and getting plenty of sleep and exercise.”

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