Why One Woman Had Oil in Her Lung for Decades

Post 8299

Why One Woman Had Oil in Her Lung for Decades


This Heart in a Jar Could Make Heart Transplants Safer

Post 8298

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]

Nearly Two-Thirds of Cancers Are Due to Random DNA ‘Mistakes’

Post 8292

Nearly Two-Thirds of Cancers Are Due to Random DNA ‘Mistakes’

‘Tree Man’ Has Surgery: What Causes This Rare Condition?

Post 8205

‘Tree Man’ Has Surgery: What Causes This Rare Condition?


Surgeons shocked to find fully formed teeth in a baby’s brain tumor

Post 8187


Surgeons shocked to find fully formed teeth in a baby’s brain tumor

2/27/14 2:20pm

Sometimes, when biology goes squirrely, it really goes squirrely. Case in point, a bizarre medical case in which a 4-month-old infant in Maryland was found to have several fully formed teeth embedded within a brain tumor. Warning: Graphic image to follow.

The boy was admitted to hospital because his head was growing faster than normal. Subsequent MRI scans showed a “heterogeneous, enhancing suprasellar mass” — but it contained multiple structures along the right side that looked startlingly like teeth that form in the lower jaw.

During the procedure to remove the tumor, the surgeons encountered multiple fully formed teeth. Fully formed! And not just bits of enamel or calcium deposits.

Subsequent analysis of the tumor revealed a craniopharyngioma, a rare brain tumor that can grow to be larger than a golf ball, but does not spread.LiveScience‘s Rachael Rettner explains more:

Researchers had always suspected that these tumors form from the same cells involved in making teeth, but until now, doctors had never seen actual teeth in these tumors, said Dr. Narlin Beaty, a neurosurgeon at the University of Maryland Medical Center, who performed the boy’s surgery along with his colleague, Dr. Edward Ahn, of Johns Hopkins Children’s Center.

“It’s not every day you see teeth in any type of tumor in the brain. In a craniopharyngioma, it’s unheard of,” Beaty said.

Craniopharyngiomas commonly contain calcium deposits, “but when we pulled out a full tooth…I think that’s something slightly different,” Beaty told Live Science.

Teeth have been found in people’s brains before, but only in tumors known as teratomas, which are unique among tumors because they contain all three of the tissue types found in an early-stage human embryo, Beaty said. In contrast, craniopharyngiomas have only one layer of tissue.

The boy’s case provides more evidence that craniopharyngiomas do indeed develop from the cells that make teeth, Beaty said.

Incredibly, the boy is doing well, but the tumor destroyed his capacity to release certain hormones, so he’ll have to undergo hormone treatments for the rest of his life.

Read more at LiveScience. The entire report can be found at the New England Journal of Medicine: “Adamantinomatous Craniopharyngioma Containing Teeth.”


Miniature Brain and Skull Found Growing Inside Teen’s Ovary

Post 8186

Miniature Brain and Skull Found Growing Inside Teen’s Ovary

Yesterday 11:17am

The teratoma contained bits of hair, skull, and surprisingly well-formed brain matter. (Image: Masayuki Shintaku et. al., 2017)

While performing a routine appendectomy on a 16-year-old girl, Japanese surgeons uncovered an ovarian tumor containing bits of hair, a thin plate of bone—and a miniature brain.

The unusual teratoma—a tumor containing tissue or organ components—measured four-inches (10 cm) across, so it was hard to miss. Analysis revealed clumps of greasy, matted hair, and a one-inch-wide (3 cm) brain-like structure covered by a thin, rudimentary skull.

Disturbingly, the miniature brain contained a brainstem-like structure, and a large amount of highly organized and differentiated cerebellum tissue. The cerebellum is a brain-part that sits below the two hemispheres, and is responsible for motor control, and some cognitive functions such as attention and language. But don’t worry—there’s no way this chunk of brain matter could feel or think.

Analysis of the mini-brain revealed highly differentiated and well-organized structures reminiscent of what’s found in the cerebellum. (Image: Masayuki Shintaku et. al., 2017)

Not to be confused with parasitic twins, teratomas happen when the cells inside organs go a bit squirrely, expressing parts of other organs and tissues that belong elsewhere in the body. These congenital tumors have been found to contain bits of hair, teeth, bone, and in some rare cases, eyes, torsos, hands, and feet. The exact cause is not known, but in the case of ovarian teratomas, it may be caused by glitching immature egg cells. Teratomas are known to happen in organs such as the brain, thyroid, liver, lung, and ovaries.

Brain cells have been observed in ovarian teratomas before, but as Japanese researcher Masayuki Shintaku told New Scientist, it’s extremely unusual for them to organize themselves into proper brain-like structures. Incredibly, the mini-brain was capable of transmitting electric impulses between neurons, just like a normal brain.

The girl didn’t express any symptoms, but teratomas are known to trigger psychological problems, such as personality changes, paranoia, confusion, agitation, seizures, and memory loss. This likely happens as a result of the body trying to get rid of the alien brain matter—but in so doing, mounts a double-attack that also affects the brain.

Thankfully, teratomas are relatively benign, and relatively easy to remove with surgery. The 16-year-old girl had her teratoma removed, and she’s made a full recovery.

[Neuropathology via New Scientist]

George is a contributing editor at Gizmodo and io9.

Your Crappy American Diet Might Leave Your Gut Bacteria Stunted

Post 8172

Your Crappy American Diet Might Leave Your Gut Bacteria Stunted

Thursday 2:08pm

Image: Rocky Mountain Laboratories/Wikimedia Commons

Adopting a healthy lifestyle might not seem that hard on the outset. You ate a lot of cheeseburgers and drank a lot of soda, and now you’re going to stop doing that. But a new study in mice suggests that it takes a while for the gut’s bacterial zoo, or microbiome, to adapt to dietary changes. If the results hold in humans, it could mean developing a healthy gut is more than a quick diet fix.

The study, which is published today in the journal Cell Host and Microbe, involved plenty of poop. The researchers first analyzed feces from a group of people who stuck to a calorie-restricted diet that optimized their nutrient intake, and another group of people who ate a so-called American diet without dietary restrictions. Then, the team raised an array of mice whose gut microbiomes included the human fecal bacteria associated with the two diets, fed these mouse models the two different diets, and measured their weight and gut bacterial makeup periodically. In another experiment, the researchers housed calorie-restricted mice and American diet mice together, and again observed how each group’s microbiome responded to either diet.

The scientists found that poop from the American diet eaters had fewer species of bacteria than poop from calorie-restricted dieters. And even after being moved to a better diet, the mice raised with an American diet-microbiome exhibited lower bacterial diversity. However, the American diet-raised mouse microbiomes responded more strongly to their new healthy diets once they moved into communities with the calorie-restricted mice.

According to Andy Benson, a professor of biotechnology at the University of Nebraska, Lincoln who was not involved with the study, the research is important for showing that different diets have an impact on the configuration of the microbiome. However, he noted a few caveats, like the fact that mice aren’t people. “The more difficult part is how we extrapolate these results to human populations,” he said. He also noted that plenty of other factors determine the microbiome other than just diet.

Benson worried that folks would get too excited about the fact that housing mice together helped American diet eaters with stunted gut microbiome diversity become more diverse. (In general, more diversity is a good thing for any ecosystem, including the gut, and we probably evolved eating a diet closer to the diversity-promoting calorie-restricted one.)

The study “definitely generates some thought, and it’s an interesting discussion among scientists. It mortifies me to think of politicians thinking about this,” he said. Plus, he wasn’t sure how this effect would manifest itself in human populations. The paper’s authors use the word “coprophagic,” meaning shit-eating, while discussing how gut bacteria might be passed between mice raised on different diets, and while they did not respond to a request for comment, I doubt people looking to live more healthy will eat the poop of dieting people.

Alessio Fasano, a pediatric gastroenterologist from Massachusetts General Hospital, speculated about what the results might mean for humans. “There’s a well-established [microbial] community dictated by prior dietary practice,” he said. “Even if you make changes in the diet, the microbiome will be hard to modify.”

Fasano emphasized that scientists aren’t so sure if a microbiome lacking diversity is the cause or consequence of gastrointestinal problems. “But when you take a cross section of people who are sick, say with Crohn’s disease, we know the differences in their microbiome are an integral part.”

[Cell Host and Microbe]

Science writer at Gizmodo | I like physics and eating