http://blogs.scientificamerican.com/the-curious-wavefunction/2012/10/...

Let’s all find out how meth works: Crowdfunding a novel scientific paradigm

By Ashutosh Jogalekar

In a previous post I described the benefits and
enduring value of Small Science. I emphasized the
fact that in the current economy and funding
environment, Small Science is likely to be
consistent while Big Science happens in fits and
starts. And I talked about how crowdsourcing and
crowdfunding could bring great value to both Big and Small Science.

Now I want to describe a crowd funded Small
Science project that could prove very valuable in
understanding the root causes of one of the most
pernicious scourges of our time – methamphetamine
addiction. Ethan Perlstein at Princeton and David
Sulzer at Columbia are interested in dissecting
the different ways in which meth acts in and on
the brain and they have taken the bold step of
pitching this as a crowdfunding project. Their
project and others like it could not only help us
develop new treatments for meth addition but they
could address a more general and key question; how do psychotropic drugs work?

It turns out that in spite of the legions of
psychiatrists prescribing a record number of
antidepressants and other medications every year,
we still don’t have a good idea how these
compounds work. The same lack of understanding
permeates our efforts in tackling the addiction
epidemic. From a chemical standpoint the
simplicity of psychotropic drugs like meth and
PCP is breathtaking. The fact that a few carbon,
hydrogen, oxygen and nitrogen atoms arranged in
and around a simple ring can cause such profound
behavioral changes in human beings continues to
beguile and fascinate us. Sadly, our knowledge of
the mechanism of action of these molecules as
well as legal psychotropic drugs has reached a kind of roadblock.

© 2012 Scientific American
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http://well.blogs.nytimes.com/2012/10/05/think-like-a-doctor-the-girl...

Think Like a Doctor: The Girl in a Coma Solved

By LISA SANDERS, M.D.

On Thursday, we challenged Well readers to try
their hand at solving the case of a comatose
young woman dropped off at the emergency room by
her friends after attending a concert the
previous night. More than 350 people wrote in,
and more than 90 of you were able to figure it out.

The Correct Diagnosis Is …  … Ecstasy-induced hyponatremia.

     Over the past 20 years there have been many
reports of young people, mostly young women, who
have had seizures or become unconscious after
taking the illegal drug Ecstasy, also known as
MDMA. The cause is a dangerously low level of
sodium in the bloodstream. The brain is
exquisitely sensitive to the exact right balance
of sodium and water, and when they are out of
whack, nausea, confusion and seizures can follow.
It’s a rare but dangerous side effect of the
drug. Nearly one in five patients reported to
have this complication died. Others had permanent brain damage.

     When this complication was first observed,
it was thought to be because of an
overconsumption of water. The drug was used
widely at concerts or “raves,” and attendees were
told to drink lots of water to replace what was
sweated out in the crowded, hot concert and dance
floors. Further research revealed that the drug
actually alters the way the brain and the kidney
work so that the body holds on to water and dumps
sodium. This change is exaggerated by the
presence of estrogen, so women are far more
likely to be affected than men. Why the drug can
have this effect on any given individual is not
well understood, but it is clear that it is not
because of an overdose or a contaminant. It
appears to be a response to the drug itself.

     Copyright 2012 The New York Times Company
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http://blogs.scientificamerican.com/thoughtful-animal/2012/10/04/cric...

  Cricket Fight Club: How is a Cricket Like a Rat?

By Jason G. Goldman

When my brother and I were young, we were very
careful to share the last bit of dessert equally.
It’s not that we were particularly magnanimous.
In their wisdom, my parents instituted a rule in
our house: one of us would divide the snack in
half, and the other would select his half. “You
cut, I choose” was a common phrase in the Goldman
household throughout the 1990s. The rule ensured
that we’d each be as equitable as possible when
in the role of divider. The kitchen ruler was
retrieved on more than one occasion. If I thought
I could have gotten away with scarfing down the
last cookie without him noticing, I’m sure I
would have done it. And I would not have been sorry.

Imagine, however, what would have happened if my
brother had decided to keep the entire last
cookie for himself and run into the living room
with it. Here’s one way he might have kept me
from snatching my fair share of the snack: find a
decent hiding spot, and if I got too close, he
could run back into the kitchen. Once back in the
kitchen, if I got too close to him, he could have
gotten up and run back to the living room. This
is called a “stimulus-response rule.” Eventually,
being the bright child that I was, I would have
caught onto the pattern and found a way to block
his path from one room to the other, increasing
the chance of getting some of the dessert.

Here’s a better method that my brother could use
to protect his treat: keep his eyes on me the
entire time, always moving away from me so that
the distance between us was, on average, fixed.
If I go right, he goes left. If I move towards
him, he backs up. Short of backing him into a
corner, my efforts would be futile. That’s
because instead of using a small set of
predictable actions, my brother could call upon a
wider range of behaviors. Its much harder for a
thief to learn how you protect your food if your
behaviors are variable than if they are
predictable. This is called a “cybernetic rule.”

© 2012 Scientific American
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http://www.sciencenews.org/view/generic/id/345517/title/Human-Neander...

Human-Neandertal mating gets a new date

By Bruce Bower

A new study suggests that present-day Europeans
share more genes with now-extinct Neandertals
than do living Africans, at least partly because
of interbreeding that took place between 37,000 and 86,000 years ago.

Cross-species mating occurred when Stone Age
humans left Africa and encountered Neandertals,
or possibly a close Neandertal relative, upon
reaching the Middle East and Europe in the latter
part of the Stone Age, says a team led by
geneticist Sriram Sankararaman of Harvard Medical School.

The new study, published online October 4 in PLOS
Genetics, indicates that at least some
interbreeding must have occurred between Homo
sapiens and Neandertals, Sankararaman says. But
it’s not yet possible to estimate how much of the
Neandertal DNA found in modern humans comes from
that interbreeding and how much derives from
ancient African hominid populations ancestral to both groups.

A separate analysis of gene variants in
Neandertals and in people from different parts of
the world also found signs of Stone Age
interbreeding outside Africa. That study,
published online April 18 in Molecular Biology
and Evolution, was led by evolutionary geneticist
Melinda Yang of the University of California, Berkeley.

Results from Sankararaman and Yang’s groups
“convincingly show that the finding of a higher
proportion of Neandertal DNA in non-Africans
compared to Africans can be best explained by
gene flow from Neandertals into modern humans,”
says evolutionary geneticist Johannes Krause of
the University of Tübingen in Germany.

  © Society for Science & the Public 2000 - 2012
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http://www.newscientist.com/article/mg21628855.200-wasp-has-hints-of-...

Wasp has hints of a clockwork brain

  by Michael Marshall

THE human brain might be the most complex object
in the known universe, but a much simpler set of
neurons is also proving to be a tough nut to crack.

A tiny wasp has brain cells so small, physics
predicts they shouldn't work at all. These
miniature neurons might harbour subtle
modifications, or they might work completely
differently from all other known neurons - mechanically.

The greenhouse whitefly parasite (Encarsia
formosa) is just half a millimetre in length. It
parasitises the larvae of whiteflies and so it
has long been used as a natural pest-controller.

To find out how its neurons have adapted to
miniaturisation, Reinhold Hustert of the
University of Göttingen in Germany examined the
insect's brain with an electron microscope. The
axons - fibres that shuttle messages between
neurons - were incredibly thin. Of 528 axons
measured, a third were less than 0.1 micrometre
in diameter, an order of magnitude narrower than
human axons. The smallest were just 0.045 m
(Arthropod Structure & Development, doi.org/jfn).

That's a surprise, because according to
calculations by Simon Laughlin of the University
of Cambridge and colleagues, axons thinner than
0.1 m simply shouldn't work. Axons carry messages
in waves of electrical activity called action
potentials, which are generated when a chemical
signal causes a large number of channels in a
cell's outer membrane to open and allow
positively charged ions into the axon. At any
given moment some of those channels may open
spontaneously, but the number involved isn't
enough to accidentally trigger an action
potential, says Laughlin - unless the axon is
very thin. An axon thinner than 0.1 m will
generate an action potential if just one channel
opens spontaneously (Current Biology, doi.org/frfwpz).

© Copyright Reed Business Information Ltd
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http://www.sciencenews.org/view/feature/id/345534/title/Scent_Into_Ac...

Scent Into Action

By Meghan Rosen

David Ferrero wasn’t expecting the jaguar to
pounce. When he approached the holding pens at
Massachusetts’ Stone Zoo, the big cat watched but
looked relaxed, lounging on her cage’s concrete
floor. Two other jaguars rested in separate cages nearby.

The jaguars usually prowled outside, in the
grassy grounds of the zoo’s enclosure. But this
afternoon, zookeepers kept the animals inside so
that Ferrero and a colleague could grab a
behind-the-scenes peek. Here, the jaguars slept
at night ­ and fed. Here, only metal bars stood
between the humans and the cats.

As Ferrero stepped closer to the cages, the
watchful female sprang up, twisting her body
toward him, front paws thumping the bars. Fully
extended, she was as tall as Ferrero.

“I think she wanted to eat me,” he says. The
zookeepers weren’t afraid, but Ferrero flinched.
He wasn’t familiar with the lean, black-spotted
feline. He was just there to pick up some pee.

Ferrero, a neurobiologist from Harvard, was
visiting the zoo to gather urine specimens for a
study linking odors to instinctual behavior in
rodents. Early lab results had hinted that a
whiff of a chemical in carnivore pee flashed a
sort of billboard message, blinking “DANGER” in
neon lights ­ enough to make animals automatically shrink away in fear.

  © Society for Science & the Public 2000 - 2012
--------------------