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Wait, is tap water drinkable in the US?

coelasquid:

There are stricter laws about how clean tap water has to be than how clean bottled water has to be, so at the very least it’s cleaner than that. Obviously there are some extreme exceptions, I’ve seen reserves in Alberta near the tar sands where the government cares fuck all about environmental management and the tap water runs black, but in most places the tap water is at least as clean as bottled stuff and if you’re still worried a filter and a decent water bottle will save money, the water table, and landfill space.

If your water is really terrible a Life Straw costs $20 and removes 99.9% of waterborne bacteria, protozoan cycts, and particles from 1000 litres of water and the company uses the proceeds of sales to send life straw filters to schools in Kenya. A litre of bottled water at the store costs about $2.50 and requires an estimated three litres of water to produce, so getting a $35 Life Straw water bottle saves something like $2.46 and two litres of water for every litre you drink (not to mention all the plastic). A friend of mine in a Natural Resources program back North loved them because you can just scoop up lake water and drink it like that without doing anything to it.

neurosciencestuff:

(Image caption: In a study of brains from children with autism, neurons in brains from autistic patients did not undergo normal pruning during childhood and adolescence. The images show representative neurons from unaffected brains (left) and brains from autistic patients (right); the spines on the neurons indicate the location of synapses. Credit: Guomei Tang, PhD and Mark S. Sonders, PhD/Columbia University Medical Center)

Children with Autism Have Extra Synapses in Brain

Children and adolescents with autism have a surplus of synapses in the brain, and this excess is due to a slowdown in a normal brain “pruning” process during development, according to a study by neuroscientists at Columbia University Medical Center (CUMC). Because synapses are the points where neurons connect and communicate with each other, the excessive synapses may have profound effects on how the brain functions. The study was published in the August 21 online issue of the journal Neuron.

A drug that restores normal synaptic pruning can improve autistic-like behaviors in mice, the researchers found, even when the drug is given after the behaviors have appeared.

“This is an important finding that could lead to a novel and much-needed therapeutic strategy for autism,” said Jeffrey Lieberman, MD, Lawrence C. Kolb Professor and Chair of Psychiatry at CUMC and director of New York State Psychiatric Institute, who was not involved in the study.

Although the drug, rapamycin, has side effects that may preclude its use in people with autism, “the fact that we can see changes in behavior suggests that autism may still be treatable after a child is diagnosed, if we can find a better drug,” said the study’s senior investigator, David Sulzer, PhD, professor of neurobiology in the Departments of Psychiatry, Neurology, and Pharmacology at CUMC.

During normal brain development, a burst of synapse formation occurs in infancy, particularly in the cortex, a region involved in autistic behaviors; pruning eliminates about half of these cortical synapses by late adolescence. Synapses are known to be affected by many genes linked to autism, and some researchers have hypothesized that people with autism may have more synapses.

To test this hypothesis, co-author Guomei Tang, PhD, assistant professor of neurology at CUMC, examined brains from children with autism who had died from other causes. Thirteen brains came from children ages two to 9, and thirteen brains came from children ages 13 to 20. Twenty-two brains from children without autism were also examined for comparison.

Dr. Tang measured synapse density in a small section of tissue in each brain by counting the number of tiny spines that branch from these cortical neurons; each spine connects with another neuron via a synapse.

By late childhood, she found, spine density had dropped by about half in the control brains, but by only 16 percent in the brains from autism patients.

“It’s the first time that anyone has looked for, and seen, a lack of pruning during development of children with autism,” Dr. Sulzer said, “although lower numbers of synapses in some brain areas have been detected in brains from older patients and in mice with autistic-like behaviors.”

Clues to what caused the pruning defect were also found in the patients’ brains; the autistic children’s brain cells were filled with old and damaged parts and were very deficient in a degradation pathway known as “autophagy.” Cells use autophagy (a term from the Greek for self-eating) to degrade their own components.

Using mouse models of autism, the researchers traced the pruning defect to a protein called mTOR. When mTOR is overactive, they found, brain cells lose much of their “self-eating” ability. And without this ability, the brains of the mice were pruned poorly and contained excess synapses. “While people usually think of learning as requiring formation of new synapses, “Dr. Sulzer says, “the removal of inappropriate synapses may be just as important.”

The researchers could restore normal autophagy and synaptic pruning—and reverse autistic-like behaviors in the mice—by administering rapamycin, a drug that inhibits mTOR. The drug was effective even when administered to the mice after they developed the behaviors, suggesting that such an approach may be used to treat patients even after the disorder has been diagnosed.

Because large amounts of overactive mTOR were also found in almost all of the brains of the autism patients, the same processes may occur in children with autism.

“What’s remarkable about the findings,” said Dr. Sulzer, “is that hundreds of genes have been linked to autism, but almost all of our human subjects had overactive mTOR and decreased autophagy, and all appear to have a lack of normal synaptic pruning. This says that many, perhaps the majority, of genes may converge onto this mTOR/autophagy pathway, the same way that many tributaries all lead into the Mississippi River. Overactive mTOR and reduced autophagy, by blocking normal synaptic pruning that may underlie learning appropriate behavior, may be a unifying feature of autism.”

Alan Packer, PhD, senior scientist at the Simons Foundation, which funded the research, said the study is an important step forward in understanding what’s happening in the brains of people with autism.

“The current view is that autism is heterogeneous, with potentially hundreds of genes that can contribute. That’s a very wide spectrum, so the goal now is to understand how those hundreds of genes cluster together into a smaller number of pathways; that will give us better clues to potential treatments,” he said.

“The mTOR pathway certainly looks like one of these pathways. It is possible that screening for mTOR and autophagic activity will provide a means to diagnose some features of autism, and normalizing these pathways might help to treat synaptic dysfunction and treat the disease.”

neurosciencestuff:

Physically fit kids have beefier brain white matter than their less-fit peers

A new study of 9- and 10-year-olds finds that those who are more aerobically fit have more fibrous and compact white-matter tracts in the brain than their peers who are less fit. “White matter” describes the bundles of axons that carry nerve signals from one brain region to another. More compact white matter is associated with faster and more efficient nerve activity.

The team reports its findings in the open-access journal Frontiers in Human Neuroscience.

“Previous studies suggest that children with higher levels of aerobic fitness show greater brain volumes in gray-matter brain regions important for memory and learning,” said University of Illinois postdoctoral researcher Laura Chaddock-Heyman, who conducted the study with kinesiology and community health professor Charles Hillman and psychology professor and Beckman Institute director Arthur Kramer. “Now for the first time we explored how aerobic fitness relates to white matter in children’s brains.”

The team used diffusion tensor imaging (DTI, also called diffusion MRI) to look at five white-matter tracts in the brains of the 24 participants. This method analyzes water diffusion into tissues. For white matter, less water diffusion means the tissue is more fibrous and compact, both desirable traits.

The researchers controlled for several variables – such as social and economic status, the timing of puberty, IQ, or a diagnosis of ADHD or other learning disabilities – that might have contributed to the reported fitness differences in the brain.

The analysis revealed significant fitness-related differences in the integrity of several white-matter tracts in the brain: the corpus callosum, which connects the brain’s left and right hemispheres; the superior longitudinal fasciculus, a pair of structures that connect the frontal and parietal lobes; and the superior corona radiata, which connect the cerebral cortex to the brain stem.
“All of these tracts have been found to play a role in attention and memory,” Chaddock-Heyman said.

The team did not test for cognitive differences in the children in this study, but previous work has demonstrated a link between improved aerobic fitness and gains in cognitive function on specific tasks and in academic settings.

“Previous studies in our lab have reported a relationship between fitness and white-matter integrity in older adults,” Kramer said. “Therefore, it appears that fitness may have beneficial effects on white matter throughout the lifespan.”

To take the findings further, the team is now two years into a five-year randomized, controlled trial to determine whether white-matter tract integrity improves in children who begin a new physical fitness routine and maintain it over time. The researchers are looking for changes in aerobic fitness, brain structure and function, and genetic regulation.

“Prior work from our laboratories has demonstrated both short- and long-term differences in the relation of aerobic fitness to brain health and cognition,” Hillman said. “However, our current randomized, controlled trial should provide the most comprehensive assessment of this relationship to date.”

The new findings add to the evidence that aerobic exercise changes the brain in ways that improve cognitive function, Chaddock-Heyman said.

“This study extends our previous work and suggests that white-matter structure may be one additional mechanism by which higher-fit children outperform their lower-fit peers on cognitive tasks and in the classroom,” she said.

Hm… I wonder why. Is it purely due to physical/motor activity or to things that happen while being active.

Music to your ears?

neurosciencestuff:

Many people listen to loud music without realizing that this can affect their hearing. This could lead to difficulties in understanding speech during age-related hearing loss which affects up to half of people over the age of 65.

image

New research led by the University of Leicester has examined…

Our genes determine the traces that stress leaves behind on our brains

neurosciencestuff:

Our individual genetic make-up determines the effect that stress has on our emotional centres. These are the findings of a group of researchers from the MedUni Vienna. Not every individual reacts in the same way to life events that produce the same degree of stress. Some grow as a result of the…

asylum-art:

Bryan Christie Design

Bryan Christie. I had seen this name over and over again in the fine print every time I saw a beautiful medical visual in a magazine. From Scientific American to Newsweek it seemed like Bryan Christie’s crisp, clear, and aesthetically pleasing visuals dominated medical editorial illustration. Problem was I had never heard of him in the rather small sphere of medical illustrators.

(via staceythinx)

neurosciencenews:

Bypass Commands From the Brain to Legs Through a Computer

Read the full article Bypass Commands From the Brain to Legs Through a Computer at NeuroscienceNews.com.

Gait disturbance in individuals with spinal cord injury is attributed to the interruption of neural pathways from brain to the spinal locomotor center, whereas neural circuits locate below and above the lesion maintain most of their functions. An artificial connection that bridges the lost pathway and connects brain to spinal circuits has potential to ameliorate the functional loss. A Japanese research group, led by Shusaku Sasada and Yukio Nishimura, has successfully made an artificial connection from the brain to the locomotion center in the spinal cord by bypassing with a computer interface. This allowed subjects to stimulate the spinal locomotion center using volitionally-controlled muscle activity and to control walking in legs.

The research is in Journal of Neuroscience. (full access paywall)

Research: “Volitional Walking via Upper Limb Muscle-Controlled Stimulation of the Lumbar Locomotor Center in Man” by Syusaku Sasada, Kenji Kato, Suguru Kadowaki, Stefan J. Groiss, Yoshikazu Ugawa, Tomoyoshi Komiyama, and Yukio Nishimura in Journal of Neuroscience. doi:10.1523/JNEUROSCI.4674-13.2014

Image: When turning off the computer-aided spinal cord bypass, the lower extremities which were in a relaxed state did not move even if the subject was swinging his/her arms. With the bypass turned on, when the subject swung his/her arms by his/her own will and a walking motion of the lower extremities began in rhythm to the motion of the arms. Credit Yukio Nishimura.

This image shows an artificial connection that connects brain to spinal circuits. Credit Yukio Nishimura.

Stuck in neutral: brain defect traps schizophrenics in twilight zone

neurosciencestuff:

People with schizophrenia struggle to turn goals into actions because brain structures governing desire and emotion are less active and fail to pass goal-directed messages to cortical regions affecting human decision-making, new research reveals.

Published in Biological Psychiatry, the finding…

Passengers who survived terrifying Air Transat flight in 2001, help psychologists uncover new clues about post-traumatic stress vulnerability

neurosciencestuff:

An extraordinary opportunity to study memory and post-traumatic stress disorder (PTSD) in a group of Air Transat passengers who experienced 30 minutes of unimaginable terror over the Atlantic Ocean in 2001 has resulted in the discovery of a potential risk factor that may help predict who is most…

fuckyeahfluiddynamics:

Superhydrophobic surfaces repel water. Both naturally occurring and manmade materials with this property share a common feature: micro- or nanoscale structures on their surface. Lotus and lily leaves are coated with tiny hairs, and synthetic coatings or micro-manufactured surfaces like the one in the video above can be made in the lab. This nanoscale roughness traps air between the surface and the water, preventing adhesion to the surface and enabling the water-repelling behavior we observe at the human scale. Although effective, these nanoscale structures are also extremely delicate, which makes widespread application of superhydrophobic coatings and textures difficult. (Video credit: G. Azimi et al.)

(via scinerds)