Scientists Link Autism To These Toxic Chemicals During Fetal Development


Scientists-Link-Autism-To-These-Toxic-Chemicals-During-Fetal-Development

The cause of autism is still unknown, but we are definitely closer to figuring it out. A new study published in the journal PLOS Computational Biology, from researchers at the University of Chicago revealed that autism and intellectual disability (ID) rates are linked with exposure to harmful environmental factors during congenital development.

Essentially what happens is during pregnancy… there are certain sensitive periods where the fetus is very vulnerable to a range of small molecules – from things like plasticisers, prescription drugs, environmental pesticides and other things. Some of these small molecules essentially alter normal development. Autism appears to be strongly correlated with rate of congenital malformations of the genitals in males across the country, this gives an indicator of environmental load and the effect is surprisingly strong. The strongest predictors for autism were associated with the environment; congenital malformations on the reproductive system in males.” (1) –  Andrey Rzhetsky, professor of genetic medicine and human genetics at the University of Chicago

The team analyzed data that covered more than one third of the U.S. population. Data from individual states and more than 2,100 counties were used.

Fetuses, particularly males, are sensitive to multiple toxins such as environmental lead, medications and a wide variety of other synthetic molecules, like pesticides, mercury and more. Exposure to these toxins during critical stages of development is thought to explain a large portion of congenital reproductive malformations.

“It’s really a very significant study, and should trigger the medical community, the scientific community and the government, looking at this especially interesting avenue for the prevention of autism. We know that one of the ways to show that there is a problem with pollution is to show through the presence of these reproductive defects and we know that there is a relationship between the presence of these defects and the presence of autism related disorders” Dr. Harbut, Providence-St John Environmental Medicine Expert

This isn’t the first time that scientists have linked autism to the environment. In 2009, Hertz-Picciotto and Lora Delwiche of the UC Dais Department of Public Health Sciences analyzed 17 years of state data that tracks developmental disabilities.

“It’s time to start looking for the environmental culprits responsible for the remarkable increase in the rate of autism in California.” (2) – Irva Hertz – Picciotto, epidemiology professor at University of California, David

Our environment is full of neurodevelopmental toxins, which means they alter how the brain grows. Mercury, polychlorinated diphenyl, lead, brominated flame retardants and pesticides are a few of many examples. Don’t forget about insecticides and herbicides.

Another recent study published in the New England Journal of Medicinecompared brain autopsies of autistic children who had died from unrelated causes to those of normal ones. The autistic brains demonstrated abnormal patches of disorganized neurons that disrupted the usual distinct layers in the brain’s cortex. The study suggests that abnormalities occurred in utero during key developmental stages between 19 to 30 weeks gestation. It’s not just the toxin, it’s the timing of the exposure as well.(3)

In the United States alone, autism rates have risen from 1:10,000 in 1981 to 1:68 in 2014. Again, multiple studies point to the prevalence of toxins in our environment as the culprit, and there are toxins in many things. No doubt about it, we might not be looking at one cause for autism, but multiple factors associated with how we choose to live our lives on a daily basis.

So, let’s take a look at some of these toxins that could be linked to autism and other neurodevelopmental disorders.

One factor I’d like to touch upon first is the fact that autism rates in Europe have remained pretty steady over the last decade.

This coincides with the fact that in more than 60 countries around the world, including Australia, Japan, and all of the countries in the European Union, there are significant restrictions or complete bans on the production and sale of GMOs and the pesticides that go with them. In the United States, government agencies have approved massive amounts of pesticides, completely ignoring the fact that they are linked to numerous health ailments.

Not long ago, the Environmental Protection Agency (EPA) recently raised the allowable concentrations of Monsanto’s glyphosate, also known as “Roundup” on food crops, edible oils and animal feed. Although we don’t know for sure, it’s important to at least consider the large increase in Genetically Modified Organism (GMOs) and the massive amount of chemicals (pesticides and herbicides) that are dumped on them every year. These pesticides have been linked to numerous health ailments.

A group of scientists put together a comprehensive review of existing data that shows how European regulators have known that Monsanto’s glyphosate causes a number of birth malformations since at least 2002. Regulators misled the public about glyphosate’s safety, and in Germany the Federal Office for Consumer Protection and Food Safety told the European Commission that there was no evidence to suggest that glyphosate causes birth defects.

See also: The Cancer Industry is Too Prosperous to Allow a Cure

This study was published by Earth Open Sources, which is an organization that uses open source collaboration to advance sustainable food production. The report was headed by Dr M. Antoniou, Head Gene Expression and Therapy Group, from the Department of Medical and Molecular Genetics at King’s College London School of Medicine, UK. Dr. Antoniou was joined by 6 other doctors who have a similar biography. The report provides a comprehensive review of the peer-reviewed scientific literature documenting the serious health hazards posed by glyphosate and Roundup herbicide formulations. You can read the entire document here.

“Our examination of the evidence leads us to the conclusion that the current approval of glyphosate and Roundup is deeply flawed and unreliable. In this report, we examine the industry studies and regulatory documents that led to the approval of glyphosate. We show that industry and regulators knew as long ago as the 1980s and 1990s that glyphosate causes malformation – but that this information was not made public. We demonstrate how EU regulators reasoned their way from clear evidence of glyphosate’s teratogenicity in industry’s own studies to a conclusion that minimized these findings in the EU Commission’s final review report”

Here is another study that shows Glyphosate can cause abnormalities. It was published in 2010 by the American Chemical Society, the research was conducted at the University of Buenos Aires, Argentina.

“The direct effect of glyphosate on early mechanisms of morphogenesis in vertebrate embryos opens concerns about the clinical findings from human offspring in populations exposed to glyphosate in agricultural fields.”

Another study outlines how glyphosate toxicity leads to suppression of critical enzymes, and as a result links the Western diet to heart disease, Alzheimer, Parkinson, autism and more. (4)

Glyphosate has also been linked to cancer, and various other health ailments. There are numerous studies documenting this and you can find our more information here.

It’s no secret that the brain of an embryo, fetus, or infant is at risk for significant and permanent damage from exposure to chemicals, like pesticides. Not long ago, a study published in the Journal Reproductive Toxicologysuccessfully identified the presence of pesticides – associated with genetically modified foods in maternal, fetal and non-pregnant women’s blood. They also found the presence of Monsanto’s Bt toxin, and warn about toxin exposure during critical stages of development. (5)

The study concluded, apart from pesticides, that Monsanto’s Bt toxins are clearly detectable and appear to cross the placenta to the fetus. Some studies have linked Monsanto’s Bt toxin to cancer, damaging kidney cells, and more, especially when they are combined with Round-up

Multiple studies outline the need for further research when it comes to GMOs before we can say they are 100 % safe for consumption.

“Given the potential toxicity of these environmental pollutants and the fragility of the fetus, more studies are needed, particularly those using the placental transfer approach. Thus, our present results will provide baseline data for future studies exploring a new area of research relating to nutrition, toxicology and reproduction in women. Today, obstetric-gynecological disorders that are associated with environmental chemicals are not known.  Thus, knowing the actual concentration of genetically modified foods in humans constitutes a cornerstone in the advancement of research in this area.” (5)

There is more research confirming that mothers who are exposed to commonly used, “safe” pesticides give birth to children with lower intelligence, structural brain abnormalities, behavioral disorders, compromised motor skills, higher rates of brain cancer and small head size. (6)(7)(8)(9)(10)(11)(12)(13)(14)(15)

In Late 2013, the European Food Safety Authority determined that pesticides, like neonicotinamides (linked to killing millions of bees, read more about that here) may negatively affect the development of neurons and brain structures in unborn babies. (16)

These are largely produced by Bayer pharmaceuticals.

“Given the ubiquitous exposure to many environmental toxicants, there needs to be renewed efforts to prevent harm. Such prevention should not await detailed evidence on individual hazards. Toxic exposure to chemical pollutants during these windows of increased susceptibility can cause disease and disability in childhood and across the entire span of human life.”(17)  – Worlds foremost pediatricians, toxicologists, environmental scientists and epidemiologists at a conference held in 2007

Scientists at the conference (quote above) emphasized that common exposure to chemicals during critical stages of development of the fetus or newborns increases their chances of contracting diabetes, cancer, thyroid damage and more.

“Chemical pollution represents a serious threat to children, and to Man’s survival.” (18)  –The Standing Committee of European Doctors.

Did you know that Americans alone are exposed to approximately 100,000 industrial chemicals? When it comes to babies, all pregnant woman are literally stuffed with hazardous chemicals. One study illustrated the tracking of just 163 chemicals, in which 99 percent of pregnant women tested positive for at least 43 different chemicals. (19)

There has even been significant concentrations of glyphosate found in the urine of people across Europe. A new study from the U.S. Geological Survey, titled “Pesticides in Mississippi Air and Rain: A Comparison Between 1995 and 2007,” reveals that Roundup herbicide (aka glyphosate) and its toxic degradation byproduct AMPA were found in over 75% of the air and rain samples tested from Mississippi in 2007.

The above makes it clear, toxins, especially when fetuses and newborns are exposed to them have the potential to be extremely harmful.  So what else are they exposed to at a young age apart from environmental toxins? They are exposed to toxins commonly found in vaccinations.

Let’s be clear, more and more researchers are now considering the fact that toxins at critical stages of development can play a role in autism (as stated and illustrated many times in this article). The vaccine/autism debate has been a controversial one, but for pro-vaccine advocates, saying there is absolutely zero cause for concern is ridiculous. Just because something hasn’t been found, does not mean there is zero cause for concern. So lets look at both sides.

A study published in March of 2013 determined that “Increasing exposure to Antibody-Stimulating Proteins and Polysaccharides (antigens) in Vaccines is Not Associated with Risk of Autism.” You can view that study here.

On the other hand, a study published in the peer-reviewed journal Translational Neurodegeneration provided epidemiological evidence supporting an association between increasing organic-Hg exposure from thimerosal-containing childhood and the risk of ASD diagnosis. You can take a look at that study here.

A paper published in the peer-reviewed International Journal of Environmental Research and Public Health titled Thimerosal Exposure and the Role of Sulfation Chemistry and Thiol Availability in Autism  concluded:

“With the rate of children diagnosed with an ASD in the US now exceeding 1 in 50 children and the rate of children with neurodevelopment/behavioral disorders in the US now exceeding 1 in 6 children, and the preceding evidence showing that there is vulnerability to ™ that would not be known without extensive testing, the preponderance of the evidence indicates that ™ should be removed from all vaccines”

The list goes on and on, bottom line, vaccines are full of toxins, and they are administered at critical stages of development, which includes pregnant woman. This study (study linking autism to toxin exposure) further pushes the importance of looking at the multiple vaccines babies are bombarded with at birth, and the toxins found within them.

It also doesn’t help that vaccine manufactures and health authorities have known about and covered up (hidden from parents) dangers associated with vaccinations in order to protect herd immunity. Documents obtained by Lucija Tomljenovic,  PhD, from the Neural Dynamics Research Group in the Department of Opthalmology and Visual Sciences at the University of British Columbia reveal that vaccine manufacturers, pharmaceutical companies and health authorities have known about multiple dangers associated with vaccines but chose to withhold them from the public. (20)

At the end of the day, you always have a choice and you shouldn’t make that decision based on fear. Ridding your personal environment from harmful pesticides and toxins does contribute to a healthier environment. From personal experience, living in a virtually chemical free environment for a few years now, the difference felt when stepping into another is overwhelming. It’s amazing how desensitized we’ve become, and how we fail to notice these things on a daily basis.

Sources:

(1) http://www.ploscompbiol.org/article/info%3Adoi%2F10.1371%2Fjournal.pcbi.1003518

(2)http://www.scientificamerican.com/article/autism-rise-driven-by-environment/

(3) http://www.nejm.org/doi/full/10.1056/NEJMoa1307491

(4) http://www.mdpi.com/1099-4300/15/4/1416

(5) https://www.uclm.es/Actividades/repositorio/pdf/doc_3721_4666.pdf

6.Rauh V, Arunajadai S, Horton M, Perera F, Hoepner L, Barr DB, et al. 2011. Seven-Year Neurodevelopmental Scores and Prenatal Exposure to Chlorpyrifos, a Common Agricultural Pesticide. Environ Health Perspect 119:1196-1201. 

  1. Bouchard M, Chevrier J, Harley K, Kogut K, Vedar M, Calderon N, Trujillo C, Johnson C, Bradman A, Barr D, Eskenazi B. Prenatal Exposure to Organophosphate Pesticides and IQ in 7-Year Old Children. Environmental Health Perspectives, 2011; DOI: 10.1289/ehp.1003185
  2. Engel S, et al. Prenatal Exposure to Organophosphates, Paraoxonase 1, and Cognitive Development in Childhood. Environmental Health Perspectives, 2011; DOI: 10.1289/ehp.1003183
  3. Horton M, et al. Impact of Prenatal Exposure to Piperonyl Butoxide and Permethrin on 36-Month Neurodevelopment. Pediatrics 2011; 127:3 e699-e706; doi:10.1542/peds.2010-0133
  4. Horton M, Kahn L, Perera F, Barr D, Rauh V. Does the home environment and the sex of the child modify the adverse effects of prenatal exposure to chlorpyrifos on child working memory? Neurotoxicology and Teratology, 2012; DOI: 10.1016/j.ntt.2012.07.004
  5. Rauh V, et al. Brain anomalies in children exposed prenatally to a common organophosphate pesticide. PNAS 2012 109 (20) 7871-7876; published ahead of print April 30, 2012, doi:10.1073/pnas.1203396109

12.Oulhote Y, Bouchard M, Urinary Metabolites of Organophosphate and Pyrethroid Pesticides and Behavioral Problems in Canadian Children Environ Health Perspect; DOI:10.1289/ehp.1306667

13.. Ostrea EM, et al. 2011. Fetal exposure to propoxur and abnormal child neurodevelopment at two years of age. Neurotoxicology.

  1. Greenop K, Peters S, Bailey H, et al. Exposure to pesticides and the risk of childhood brain tumors. Cancer Causes & Control. April 2013
  2. Kimura-Kuroda J, Komuta Y, Kuroda Y, Hayashi M, Kawano H (2012) Nicotine-Like Effects of the Neonicotinoid Insecticides Acetamiprid and Imidacloprid on Cerebellar Neurons from Neonatal Rats. PLoS ONE 7(2): e32432. doi:10.1371/journal.pone.003243

(16) http://www.efsa.europa.eu/en/press/news/131217.htm

(17) http://articles.latimes.com/2007/may/25/nation/na-fetuses25

(18)  http://www.artac.info/fr/appel-de-paris/texte-en-six-langues/english_000082.html

(19) Tracey J. Woodruff, Ami R. Zota, Jackie M. Schwartz. Environmental Chemicals in Pregnant Women in the US: NHANES 2003-2004. Environmental Health Perspectives, 2011; DOI: 10.1289/ehp.1002727

http://www.truth-out.org/news/item/23267-autism-nation-americas-chemical-brain-drain

(20) http://nsnbc.me/wp-content/uploads/2013/05/BSEM-2011.pdf 

Quantum ‘world record’ smashed


An artistic rendition of a 'bound exciton' quantum state used to prepare and read out the state of the qubits
Quantum systems are notoriously fickle to measure and manipulate

A fragile quantum memory state has been held stable at room temperature for a “world record” 39 minutes – overcoming a key barrier to ultrafast computers.

“Qubits” of information encoded in a silicon system persisted for almost 100 times longer than ever before.

Quantum systems are notoriously fickle to measure and manipulate, but if harnessed could transform computing.

The new benchmark was set by an international team led by Mike Thewalt of Simon Fraser University, Canada.

“Start Quote

“39 minutes may not seem very long. But these lifetimes are many times longer than previous experiments”

Stephanie Simmons Oxford University

“This opens the possibility of truly long-term storage of quantum information at room temperature,” said Prof Thewalt, whose achievement is detailed in the journal Science.

In conventional computers, “bits” of data are stored as a string of 1s and 0s.

But in a quantum system, “qubits” are stored in a so-called “superposition state” in which they can be both 1s and 0 at the same time – enabling them to perform multiple calculations simultaneously.

The trouble with qubits is their instability – typical devices “forget” their memories in less than a second.

There is no Guinness Book of quantum records. But unofficially, the previous best for a solid state system was 25 seconds at room temperature, or three minutes under cryogenic conditions.

In this new experiment, scientists encoded information into the nuclei of phosphorus atoms held in a sliver of purified silicon.

Magnetic field pulses were used to tilt the spin of the nuclei and create superposition states – the qubits of memory.

The team prepared the sample at -269C, close to absolute zero – the lowest temperature possible.

Artist's impression of a phosphorus atom qubit in silicon, showing a ticking clock

When they raised the system to room temperature (just above 25C) the superposition states survived for 39 minutes.

What’s more, they found they could manipulate the qubits as the temperature of the system rose and fell back towards absolute zero.

At cryogenic temperatures, their quantum memory system remained coherent for three hours.

“Having such robust, as well as long-lived, qubits could prove very helpful for anyone trying to build a quantum computer,” said co-author Stephanie Simmons of Oxford University’s department of materials.

“39 minutes may not seem very long. But these lifetimes are many times longer than previous experiments.

“We’ve managed to identify a system that seems to have basically no noise.”

However she cautions there are still many hurdles to overcome before large-scale quantum computations can be performed.

For one thing, their memory device was built with a highly purified form of silicon – free from the magnetic isotopes which interfere with the spin of nuclei.

For another, the spins of the 10 billion or so phosphorus ions used in this experiment were all placed in the same quantum state.

Continue reading the main story

“Start Quote

“What’s most important is this is silicon. The global investment in this material means it has a lot of potential for engineering”

Dr Thaddeus Ladd HRL Laboratories

Whereas to run calculations, physicists will need to place different qubits in different states – and control how they couple and interact.

“To have them controllably talking to one another – that would address the last big remaining challenge,” said Dr Simmons.

Independent experts in the quantum field said the new record was an “exciting breakthrough” that had long been predicted.

“This result represents an important step towards realising quantum devices,” said David Awschalom, professor in Spintronics and Quantum Information, at the University of Chicago.

“However, a number of intriguing challenges still remain. For instance – will it be possible to precisely control the local electron-nuclear interaction to enable initialisation, storage, and readout of the nuclear spin states?”

The previous “world record” for a solid state quantum system at room temperature – 25 seconds – was held by Dr Thaddeus Ladd, formerly of Stanford University‘s Quantum Information Science unit, now working for HRL Laboratories.

“It’s remarkable that these coherence states could be held for so long in a measurable system – as measurement normally introduces noise,” he told BBC News.

“It’s also a nice surprise that nothing goes wrong warming up and cooling the sample again – from an experimental point of view that’s pretty remarkable.

“What is perhaps most important is that this is silicon. The global investment in this particular material means that it has a lot of potential for engineering.”

Monkey feels touch with prosthetic hand.


A sense of touch lets you connect with loved ones, makes your limbs feel your own, and helps you to interact with your surroundings. But people who are paraplegics or have lost limbs have to navigate the world without this most fundamental of sensory inputs.

Sliman Bensmaia at the University of Chicago, Illinois, is working to change that with a new model for transmitting a sense of touch to the brain that bypasses regular routes. He hopes it will be a blueprint for constructing prosthetics that convey touch in the same way that natural limbs do.

One day they'll feel the same <i>(Image: PNAS, 2013)</i>

To start, Bensmaia and his colleagues trained rhesus macaques to focus their gaze in different directions depending on whether their index finger or fourth finger were being prodded.

Microelectrodes were then placed in an area of the brain called the primary somatosensory cortex. This area represents an entire map of the body, with each neuron responsible for sensing when a different part of the skin is touched.

Microelectrodes record the activity pattern of neurons. They can also be used in reverse – to deliver electrical stimulation to make neurons fire.

Fourth finger exercise

Next, the team recorded what activity occurred and where it registered in the somatosensory cortex when a monkey had its index or fourth finger poked.

Then they stimulated the brain using the same pattern of activity. The monkeys reacted as if they had been touched – fixing their gaze in the direction they been taught in response to a poke.

In similar experiments, the monkeys were also able to differentiate between pokes of varying strength to a prosthetic hand that transmitted the information to their brain via the microelectrodes.

“Information about location and pressure of a touch is often unavailable visually or is inadequate to guide motor behaviour for people with prosthetics,” Bensmaia says. “But it is crucial. Without it we crush or drop objects in our grasp.”

He hopes that one day prosthetic sensors will be able to transmit signals to implants in humans that dispatch the correct pattern of electrical pulses to the brain to allow them to sense touch. Such prosthetics, he says, will confer a greater feeling of embodiment – the sense that your limbs feel like a part of your body, and foster richer interactions with the environment.

“Maybe this will help a person touch a loved one for the first time,” Bensmaia says. “That’s powerful.”

Though electrode implants has been used in humans, Bensmaia says that hurdles remain. Implants must be safe and durable enough to remain in the brain over a long period of time, as well as adaptable enough to function as a person’s brain changes with age.

Despite the obstacles, Lee Miller at Northwestern University in Evanston, Illinois, says that Bensmaia’s biomimetic approach holds great promise for prosthetics, which have limited sensory capacity at the moment.

“Bensmaia is trying to reproduce a natural pattern of sensory activity and that’s a big distinction,” he says. “The best approach to conveying touch will likely be imitating as faithfully as possible the brain’s own signalling.”

Scientists Recreate The Sense Of Touch With Direct-To-Brain Electrical Signals .


We’ve seen some very cool prosthetic arms recently, including ones people are able to control—just as they control biological arms—with their thoughts. So what’s one of the next great frontiers for prosthetics? Letting people experience touches through them, too.

photo of an experimental prosthetic arm

The human sense of touch does a lot more than let people enjoy fresh sheets or soft kitties. It’s also crucial for helping people judge how hard to hold stuff they want to pick up, or whether they’ve got a good grip on something slippery. In a feature published earlier this year, Nature News talked with one prosthetic arm user, Igor Spetic, who accidentally broke dishes and bruised fruit he tried to hold with his device. If he had a prosthesis that had a sense of touch, he told Nature News, “I’d probably lay everything on the countertop and just start grabbing stuff. I’d be so excited.”

Now one research group is reporting a major step toward a touchy-feely prosthetic. A team of researchers from the University of Chicago and Johns Hopkins University performed a series of experiments that showed they could send electrical signals directly to the brains of rhesus macaques and that the macaques were able to interpret the signals as touches on different parts of their hands. Another series of experiments showed rhesus macaques could interpret different direct-to-brain signals as touches of varying pressure. A third explored whether direct-to-brain signals work quickly enough to be able to accurately tell macaques when a prosthetic is touching something and when it stops the touch. (The signals seem to move too slowly to be totally accurate, but the researchers thought of some workarounds, which they discussed in a paper they published today in the Proceedings of the National Academy Sciences.)

The macaques were quickly able to interpret electrical brain stimulation as analogues to physical touches.

The team will surely work to incorporate those findings into a device. For one thing, some of the researchers’ experiments actually involved a prosthetic finger that sent signals to the research monkeys‘ brains. For another, Johns Hopkins University is working on a prototype that’s the most sophisticated touch-enabled prosthesis in the world, with more than 100 sensors, Nature News reports.

There was one especially cool thing the Chicago-Johns Hopkins team demonstrated. While it’s impossible to know exactly what the monkeys feel when they get electrical buzzes to their brains, one series of experiments showed the animals were quickly able to interpret electrical brain stimulation as analogues to physical touches.

First, the researchers taught rhesus macaques to look either left or right after feeling two presses into their hands—say, pressure on the index finger, and then pressure on the pinky finger. After running several trials to make sure the monkeys learned the press-look game as well as they could, the researchers stimulated parts of the monkeys’ brains they’d learned corresponded with different parts of the monkeys’ hands. The two macaques in whom the researchers tested this looked in the correct direction 81 percent and 72 percent of the time, the very first time researchers sent electrical signals to their brains.

This research could help scientists develop touch-enabled prosthetics that send signals that are intuitive for people to interpret, the researchers wrote in their paper.

It’ll be years yet before technology like this will show up in prosthetics for people, however. It is invasive, requiring wiring to the brain, so researchers will have to do a lot to show it’s safe and durable. (Nobody wants to have to undergo frequent brain implants for tune-ups or software updates.) It’s also not clear yet whether electrical signals sent to the brain are able to reproduce touches as specific as human or monkey skin is able to feel. The electric signals could be lower resolution than true touches.

President Bush’s unnecessary heart surgery.


Vinay Prasad is chief fellow of medical oncology at the National Cancer Institute and the National Institutes of Health. Adam Cifu is a professor of medicine at the University of Chicago.

Former president George W. Bush, widely regarded as a model of physical fitness, received a coronary artery stent on Tuesday. Few facts are known about the case, but what is known suggests the procedure was unnecessary.

Before he underwent his annual physical, Mr. Bush reportedly had no symptoms. Quite the opposite: His exercise tolerance was astonishing for his age, 67. He rode more than 30 miles in the heat on a bike ride for veterans injured in the wars in Iraq and Afghanistan.

If Mr. Bush had visited a general internist practicing sound, evidence-based care, he would not have had cardiac testing. Instead, the doctor would have had conducted age-appropriate cancer screening. For the former president, this would include only colon cancer screening. It no longer would include even prostate-specific antigen testing for cancer. The doctor would have screened for cholesterol, checked for hypertension and made sure the patient was up to date on age-appropriate vaccinations, including those for pneumococcal pneumonia and shingles. Presumably Mr. Bush got these things, and he got the cardiac test as well.

What value does a stress test add for an otherwise healthy 67-year-old?No study has shown that this examination improves outcomes. The trials that have been done for so-called routine stress testing examined higher-risk patients. They found that performing stress tests on people at high risk of cardiovascular disease may detect blockages but does not improve symptoms or survival. Routine stress testing does, however, increase the use of procedures such as coronary stenting.

Unfortunately, Mr. Bush, like many VIPs, may be paying the price of these in-depth investigations. His stress test revealed an abnormality, prompting another test: a CT angiogram. This study showed a blockage, which was stented open during an invasive procedure. It is worth noting that at least two large randomized trials show that stenting these sorts of lesions does not improve survival. Because Mr. Bush had no symptoms, it is impossible that he felt better after these procedures.

Instead, George W. Bush will have to take two blood thinners, aspirin and Plavix, for at least a month and probably a year. (The amount of time a blood thinner is needed depends on the type of stent placed). While he takes these medications, he will have a higher risk of bleeding complications with no real benefit.

Although this may seem like an issue important only to the former president, consider the following: Although the price of excessive screening of so-called VIPs is usually paid for privately, follow-up tests, only “necessary” because of the initial unnecessary screening test, are usually paid for by Medicare, further stressing our health-care system. The media coverage of interventions like Mr. Bush’s also leads patients to pressure their own doctors for unwarranted and excessive care.

Source: http://www.washingtonpost.com

 

Physicists Twist Water into Knots .


 

physicists-twist-water-into-knots_1

A 3-D-printed vortex-maker may improve understanding of braided fluids in nature, such as in the sun’s outer atmosphere, superconductive materials, liquid crystals and quantum fields

More than a century after the idea was first floated, physicists have finally figured out how to tie water in knots in the laboratory. The gnarly feat, described today in Nature Physics, paves the way for scientists to experimentally study twists and turns in a range of phenomena — ionized gases like that of the Sun’s outer atmosphere, superconductive materials, liquid crystals and quantum fields that describe elementary particles.

Lord Kelvin proposed that atoms were knotted “vortex rings” — which are essentially like tornado bent into closed loops and knotted around themselves, as Daniel Lathrop and Barbara Brawn-Cinani write in an accompanying commentary. In Kelvin’s vision, the fluid was the theoretical ‘aether’ then thought to pervade all of space. Each type of atom would be represented by a different knot.

Kelvin’s interpretation of the periodic table never went anywhere, but his ideas led to the blossoming of the mathematical theory of knots, part of the field of topology. Meanwhile, scientists also have come to realize that knots have a key role in a host of physical processes.

Creating a knot in a fluid bears little resemblance to tying a knot in a shoelace, say Dustin Kleckner and William Irvine, physicists at the University of Chicago in Illinois. The entire three-dimensional (3D) volume of a fluid within a confined region, such as a vortex, must be twisted. Kleckner and Irvine have now created a knotted vortex using a miniature version of an airplane wing built with a 3D printer.

During an airplane’s flight, a wing induces a rotational or vortex-like motion of air currents that gives lift to an airplane. When a wing at rest suddenly accelerates, it creates two vortices of air circulating in opposite directions. The researchers submerged their tiny wings in a tank of water and gave it a sudden acceleration to create a knotted structure (videos below and at top).

Capturing images of the knot was another technical tour-de-force. Fluid dynamicists often use colored dye to trace the motion of fluids, but Kleckner and Irvine injected tiny gas bubbles into the water that were drawn to the center of the knotted vortex by buoyancy forces. A high-speed laser scanner capable of producing CT-scan views of the fluid at 76,000 frames per second enabled the researchers to reconstruct the 3D arrangement of the bubbles, thus revealing the knots.

“The authors have managed a remarkable achievement to be able to images these vortex knots,” says Mark Dennis, an optical physicist at the University of Bristol, UK, who has made knotted vortices from light beams. The new study, he adds, transforms abstract notions about physical processes involving knots into testable ideas in the laboratory.

“Knotted vortices are an ideal model system for allowing us to study the precise way in which knots untie themselves in a real physical field,” says Irvine.

Knotted vortices show up in several branches of physics. Particle physicists, for example, have proposed that ‘glueballs’, hypothetical agglomerations of gluons — the elementary particles that bind quarks to form protons and neutrons — are tightly knotted quantum fields.

And in January, scientists reported evidence of ‘unbraiding’ or relaxation of knotted magnetic fields that may help to transfer heat to the Sun’s corona, or outer atmosphere, explaining why the plasma in this region is much hotter than the Sun’s surface.

Source: Scientific American.

Homolog of Mammalian Neocortex Found in Bird Brain.


A seemingly unique part of the human and mammalian brain is the neocortex, a layered structure on the outer surface of the organ where most higher-order processing is thought to occur. But new research at the University of Chicago has found the cells similar to those of the mammalian neocortex in the brains of birds, sitting in a vastly different anatomical structure.

he work, published in Proceedings of the National Academy of Sciences, confirms a 50-year-old hypothesis about the identity of a mysterious structure in the bird brain that has provoked decades of scientific debate. The research also sheds new light on the evolution of the brain and opens up new animal models for studying the neocortex.

“If you want to study motor neurons or dopamine cells, which are biomedically important, you can study them in mammals, in chick embryos, in zebrafish. But for these neurons of the cerebral cortex, we could only do that in mammals before,” said Clifton Ragsdale, PhD, associate professor of neurobiology at University of Chicago Biological Sciences and senior author of the study. “Now, we can take advantage of these other experimental systems to ask how they are specified, can they regenerate, and other questions.”

Both the mammalian neocortex and a structure in the bird brain called the dorsal ventricular ridge (DVR) originate from an embryonic region called the telencephalon. But the two regions mature into very different shapes, with the neocortex made up of six distinct cortical layers while the DVR contains large clusters of neurons called nuclei.

Because of this divergent anatomy, many scientists proposed that the bird DVR does not correspond to the mammalian cortex, but is analogous to another mammalian brain structure called the amygdala.

“All mammals have a neocortex, and it’s virtually identical across all of them,” said Jennifer Dugas-Ford, PhD, postdoctoral researcher at the University of Chicago and first author on the paper. “But when you go to the next closest group, the birds and reptiles, they don’t have anything that looks remotely similar to neocortex.”

But in the 1960s, neuroscientist Harvey Karten studied the neural inputs and outputs of the DVR, finding that they were remarkably similar to the pathways traveling to and from the neocortex in mammals. As a result, he proposed that the DVR performs a similar function to the neocortex despite its dramatically different anatomy.

Dugas-Ford, Ragsdale and co-author Joanna Rowell decided to test Karten’s hypothesis by using recently discovered sets of molecular markers that can identify specific layers of mammalian cortex: the layer 4 “input” neurons or layer 5 “output” neurons. The researchers then looked for whether these marker genes were expressed in the DVR nuclei.

In two different bird species — chicken and zebra finch — the level 4 and 5 markers were expressed by distinct nuclei of the DVR, supporting Karten’s hypothesis that the structure contains cells homologous to those of mammalian neocortex.

“Here was a completely different line of evidence,” Ragsdale said. “There were molecular markers that picked out specific layers of cortex; whereas the original Karten theory was based just on connections, and some people dismissed that. But in two very distant birds, all of the gene expression fits together very nicely with the connections.”

Dugas-Ford called the evidence “really incredible.”

“All of our markers were exactly where they thought they would be in the DVR when you’re comparing them to the neocortex,” she said.

A similar experiment was conducted in a species of turtle, and revealed yet another anatomical possibility for these neocortex-like cells. Instead of a six-layer neocortex or a cluster of nuclei, the turtle brain had layer 4- and 5-like cells distributed along a single layer of the species’ dorsal cortex.

“I think that’s the interesting part, that you can have all these different morphologies built with the same cell types, just in different conformations,” Rowell said. “It’s a neocortex or a big clump of nuclei, and then in reptiles they have an unusual dorsal cortex unlike either of those.”

Future experiments will test the developmental steps that shape these neurons into various structures, and the relative pros and cons of these anatomical differences. The complex language and tool-use of some bird species suggests that the nuclear organization of this pathway is also capable of supporting advanced functions — and even may offer advantages over the mammalian brain.

“If you wanted to have a special nuclear processing center in Broca’s area to carry out language processing, you can’t do that in a mammal,” Ragsdale said. “But in a bird they have these special nuclei that are involved in vocalization. It’s as if you have additional flexibility: You can have shorter circuits, longer circuits, you can have specialized processing centers.”

Beyond the structural differences, the discovery of homologous neocortex cell types will allow scientists to study cortical neurons in bird species such as the chicken, a common model used for examining embryonic development. Such research could help scientists more easily study the neurons lost in paralysis, deafness, blindness, and other neurological conditions.

Source: http://www.sciencedaily.com