Author Archives: Attention to the Unseen

Direct connection discovered between the brain and the immune system

Science Daily reports: In a stunning discovery that overturns decades of textbook teaching, researchers at the University of Virginia School of Medicine have determined that the brain is directly connected to the immune system by vessels previously thought not to exist. That such vessels could have escaped detection when the lymphatic system has been so thoroughly mapped throughout the body is surprising on its own, but the true significance of the discovery lies in the effects it could have on the study and treatment of neurological diseases ranging from autism to Alzheimer’s disease to multiple sclerosis.

“Instead of asking, ‘How do we study the immune response of the brain?’ ‘Why do multiple sclerosis patients have the immune attacks?’ now we can approach this mechanistically. Because the brain is like every other tissue connected to the peripheral immune system through meningeal lymphatic vessels,” said Jonathan Kipnis, PhD, professor in the UVA Department of Neuroscience and director of UVA’s Center for Brain Immunology and Glia (BIG). “It changes entirely the way we perceive the neuro-immune interaction. We always perceived it before as something esoteric that can’t be studied. But now we can ask mechanistic questions.”

“We believe that for every neurological disease that has an immune component to it, these vessels may play a major role,” Kipnis said. “Hard to imagine that these vessels would not be involved in a [neurological] disease with an immune component.”

Kevin Lee, PhD, chairman of the UVA Department of Neuroscience, described his reaction to the discovery by Kipnis’ lab: “The first time these guys showed me the basic result, I just said one sentence: ‘They’ll have to change the textbooks.’ There has never been a lymphatic system for the central nervous system, and it was very clear from that first singular observation — and they’ve done many studies since then to bolster the finding — that it will fundamentally change the way people look at the central nervous system’s relationship with the immune system.” [Continue reading…]

Facebooktwittermail

The problem of translation

Gideon Lewis-Kraus writes: One Enlightenment aspiration that the science-­fiction industry has long taken for granted, as a necessary intergalactic conceit, is the universal translator. In a 1967 episode of “Star Trek,” Mr. Spock assembles such a device from spare parts lying around the ship. An elongated chrome cylinder with blinking red-and-green indicator lights, it resembles a retracted light saber; Captain Kirk explains how it works with an off-the-cuff disquisition on the principles of Chomsky’s “universal grammar,” and they walk outside to the desert-­island planet of Gamma Canaris N, where they’re being held hostage by an alien. The alien, whom they call The Companion, materializes as a fraction of sparkling cloud. It looks like an orange Christmas tree made of vaporized mortadella. Kirk grips the translator and addresses their kidnapper in a slow, patronizing, put-down-the-gun tone. The all-­powerful Companion is astonished.

“My thoughts,” she says with some confusion, “you can hear them.”

The exchange emphasizes the utopian ambition that has long motivated universal translation. The Companion might be an ion fog with coruscating globules of viscera, a cluster of chunky meat-parts suspended in aspic, but once Kirk has established communication, the first thing he does is teach her to understand love. It is a dream that harks back to Genesis, of a common tongue that perfectly maps thought to world. In Scripture, this allowed for a humanity so well ­coordinated, so alike in its understanding, that all the world’s subcontractors could agree on a time to build a tower to the heavens. Since Babel, though, even the smallest construction projects are plagued by terrible delays. [Continue reading…]

Facebooktwittermail

Every virus a person has had can be seen in a drop of blood

The New York Times reports: Using less than a drop of blood, a new test can reveal nearly every virus a person has ever been exposed to, scientists reported on Thursday.

The test, which is still experimental, can be performed for as little as $25 and could become an important research tool for tracking patterns of disease in various populations, helping scientists compare the old and the young, or people in different parts of the world.

It could also be used to try to find out whether viruses, or the body’s immune response to them, contribute to chronic diseases and cancer, the researchers said.

“I’m sure there’ll be lots of applications we haven’t even dreamed of,” said Stephen J. Elledge, the senior author of the report, published in the journal Science, and a professor of genetics at Harvard Medical School and Brigham and Women’s Hospital.

“That’s what happens when you invent technology — you can’t imagine what people will do with it,” Dr. Elledge said. “They’re so clever.”

The test can detect past exposure to more than 1,000 strains of viruses from 206 species — pretty much the entire human “virome,” meaning all the viruses known to infect people. The test works by detecting antibodies, highly specific proteins that the immune system has made in response to viruses. [Continue reading…]

Facebooktwittermail

A crisis at the edge of physics

Adam Frank and Marcelo Gleiser write: Do physicists need empirical evidence to confirm their theories?

You may think that the answer is an obvious yes, experimental confirmation being the very heart of science. But a growing controversy at the frontiers of physics and cosmology suggests that the situation is not so simple.

A few months ago in the journal Nature, two leading researchers, George Ellis and Joseph Silk, published a controversial piece called “Scientific Method: Defend the Integrity of Physics.” They criticized a newfound willingness among some scientists to explicitly set aside the need for experimental confirmation of today’s most ambitious cosmic theories — so long as those theories are “sufficiently elegant and explanatory.” Despite working at the cutting edge of knowledge, such scientists are, for Professors Ellis and Silk, “breaking with centuries of philosophical tradition of defining scientific knowledge as empirical.”

Whether or not you agree with them, the professors have identified a mounting concern in fundamental physics: Today, our most ambitious science can seem at odds with the empirical methodology that has historically given the field its credibility. [Continue reading…]

Facebooktwittermail

Tribes in peril

Heather Pringle writes: In a spacious, art-filled apartment in Brasília, 75-year-old Sydney Possuelo takes a seat near a large portrait of his younger self. On the canvas, Possuelo stares with calm assurance from the stern of an Amazon riverboat, every bit the famous sertanista, or Amazon frontiersman, that he once was. But on this late February morning, that confidence is nowhere to be seen. Possuelo, now sporting a beard neatly trimmed for city life, seethes with anger over the dangers now threatening the Amazon’s isolated tribespeople. “These are the last few groups of humans who are really free,” he says. “But we will kill them.”

For decades, Possuelo worked for Brazil’s National Indian Foundation (FUNAI), the federal agency responsible for the country’s indigenous peoples. In the 1970s and 1980s, he and other sertanistas made contact with isolated tribespeople so they could be moved off their land and into settlements. But Possuelo and others grew alarmed by the human toll. The newly contacted had no immunity to diseases carried by outsiders, and the flu virus, he recalls, “was like a suicide bomber,” stealing into a village unnoticed. Among some groups, 50% to 90% died (see sidebar, p. 1084). In 1987, Possuelo and fellow sertanistas met to try to stop this devastation.

In Brasília, a futuristic city whose central urban footprint evokes the shape of an airplane, the frontiersmen agreed that contact was inherently damaging to isolated tribespeople. They drew up a new action plan for FUNAI, based solidly on the principle of no contact unless groups faced extinction. They recommended mapping and legally recognizing the territories of isolated groups, and keeping out loggers, miners, and settlers. If contact proved unavoidable, protecting tribespeople’s health should be top priority.

The recommendations became FUNAI policy, and a model for other countries where isolated populations are emerging, such as neighboring Peru (see companion story, p. 1072). In remote regions, FUNAI has designated a dozen “protection fronts” — official front lines in the battle to defend isolated groups, each dotted with one or more frontier bases to track tribes and sound the alarm when outsiders invade. In an interview in February, FUNAI’s interim president, Flávio Chiarelli, told Science that his agency is “doing great” at protecting the country’s isolated tribes.

But some experts say that as the pace of economic activity in the Amazon accelerates, the protection system that was once the envy of South America is falling apart. [Continue reading…]

Facebooktwittermail

The dysevolution of humanity

Jeff Wheelwright writes: I sat in my padded desk chair, hunched over, alternately entering notes on my computer and reading a book called The Story of the Human Body. It was the sort of book guaranteed to make me increasingly, uncomfortably aware of my own body. I squirmed to relieve an ache in my lower back. When I glanced out the window, the garden looked fuzzy. Where were my glasses? My toes felt hot and itchy: My athlete’s foot was flaring up again.

I returned to the book. “This chapter focuses on just three behaviors … that you are probably doing right now: wearing shoes, reading, and sitting.” OK, I was. What could be more normal?

According to the author, a human evolutionary biologist at Harvard named Daniel Lieberman, shoes, books and padded chairs are not normal at all. My body had good reason to complain because it wasn’t designed for these accessories. Too much sitting caused back pain. Too much focusing on books and computer screens at a young age fostered myopia. Enclosed, cushioned shoes could lead to foot problems, including bunions, fungus between the toes and plantar fasciitis, an inflammation of the tissue below weakened arches.

Those are small potatoes compared with obesity, Type 2 diabetes, osteoporosis, heart disease and many cancers also on the rise in the developed and developing parts of the world. These serious disorders share several characteristics: They’re chronic, noninfectious, aggravated by aging and strongly influenced by affluence and culture. Modern medicine has come up with treatments for them, but not solutions; the deaths and disabilities continue to climb.
lieberman

An evolutionary perspective is critical to understanding the body’s pitfalls in a time of plenty, Lieberman suggests. [Continue reading…]

Facebooktwittermail

The neuroscience of a sense of place

Rick Paulas writes: Comedian Eddie Pepitone once said — and I’m paraphrasing here — that there are no great neighborhoods in Los Angeles, only great blocks. The stretch of Echo Park on Sunset Boulevard between Glendale and Logan is one. The establishments on that short stretch include an upscale wine bar, a hipster concert venue, a vegan restaurant, a deep dish pizza place, cheap thrift stores, not-so-cheap “vintage” stores selling roughly the same stuff, a check-cashing joint, a few fast food chains, and even a supermarket for time travelers.

While it’s not the most diverse cross-section you’ll find in the city, the block can be used as a social barometer when brought up in conversations. Mention the stretch, and whatever landmark the other person’s familiar with tells the tale of the socioeconomic sphere they inhabit; the landmark that puts a gleam of recognition in the other person’s eye says everything about their story.

Blocks and neighborhoods aren’t concrete concepts that mean the same thing to everyone, unlike, say, things like “apple” or “sky.” Points of reference shift depending on the person that’s using that reference, so blocks/neighborhoods are more like alternate realities laid atop one another, like plastic sheets on an overhead projector. There’s even a phrase for the study of this murky concept: mental maps. They can help us understand why some neighborhoods thrive, others die, and how changes are made.

The theory of mental (or cognitive) maps was first developed in 1960 by Massachusetts Institute of Technology professor Kevin Lynch in his book The Image of the City. Rather than relying on how cartographers saw a city, Lynch asked residents to draw a map, from memory, depicting how their city was arranged. He found that five elements compose a person’s understanding of where they are: landmarks, paths, edges, districts, and nodes. Landmarks are reference points, paths connect them, edges mark boundaries, and the other elements define larger areas that contain some combination of each of those designations.

Neuroscience backs up Lynch’s findings. In 1971, Jon O’Keefe discovered “place cells” in the hippocampus, neurons that activate when an animal enters an environment. The neurons calculate a current location based on what the animal can see, as well as through “dead reckoning” — that is, accounting based on subconscious calculations using previous positions in the recent past and how quickly it traveled over a stretch of time. In 2005, husband-and-wife team Edvard and May-Britt Moser discovered “grid cells,” neurons that fire in a grid-like pattern to measure distances and direction. O’Keefe and the Mosers all won Nobel Prizes in 2014 for their discoveries. [Continue reading…]

Facebooktwittermail