5th May 2014, 11:42 AM #1071
Re: Health Bulletin
World’s fastest circuit board modelled on the human brain created
Engineers have now created the world's fastest circuit board modelled on the human brain - a device that would help prosthetic limbs to be controlled by a single chip which would decode brain signals into movements without overheating the brain.
The Neurogrid can simulate one million neurons and billions of synapses or brain connections - far more than other "brain-mimicking" devices.
At present, the speed of computers pale in front of a real human brain which is 9,000 times faster and uses significantly less power than a typical PC.
Scientists therefore created the circuit board which is the size of an IPad consisting of 16 custom-designed "Neurocore" chips.
The scientists from Stanford University in California said "Neurogrid can simulate orders of magnitude more neurons and synapses than other brain mimics on the power it takes to run a tablet computer."
"This could help develop a chip as fast and efficient as the human brain that could drive prosthetic limbs with the speed and complexity of our own actions," they said.
The National Institutes of Health funded development of this million-neuron prototype with a five-year Award. It one day hopes to solve challenges such as controlling a humanoid robot.
Kwabena Boahen from Stanford said "From a pure energy perspective, the brain is hard to match. The human brain, with 80,000 times more neurons than Neurogrid, consumes only three times as much power. Achieving this level of energy efficiency while offering greater configurability and scale is the ultimate challenge."
"Neurogrid is the most cost-effective effort developed so far, but each circuit board still costs about $4000 so the researchers are now working to reduce the cost 100-fold. However, there's still a long way to go in terms of matching the power of the human brain," Boahen added. A small prosthetic arm in Boahen's lab is currently controlled by Neurogrid to execute movement commands in real time.
Boahen notes that "Neurogrid is about 100,000 times more energy efficient than a personal computer simulation of 1 million neurons."
5th May 2014, 11:42 AM #1072
Re: Health Bulletin
Blood from the young may hold a key to reversing aging, research teams agree
Two teams of scientists published studies on Sunday showing that blood from young mice reverses aging in old mice, rejuvenating their muscles and brains. As ghoulish as the research may sound, experts said that it could lead to treatments for disorders like Alzheimer's disease and heart disease.
"I am extremely excited," said Rudolph Tanzi, a professor of neurology at Harvard Medical School, who was not involved in the research. "These findings could be a game changer."
The research builds on centuries of speculation that the blood of young people contains substances that might rejuvenate older adults.
In the 1950s, Clive M McCay of Cornell University and his colleagues tested the notion by delivering the blood of young rats into old ones. To do so, they joined rats in pairs by stitching together the skin on their flanks. After this procedure, called parabiosis, blood vessels grew and joined the rats' circulatory systems. The blood from the young rat flowed into the old one, and vice versa.
Later, McCay and his colleagues performed necropsies and found that the cartilage of the old rats looked more youthful than it would have otherwise. But the scientists could not say how the transformations happened. There was not enough known at the time about how the body rejuvenates itself.
It later became clear that stem cells are essential for keeping tissues vital. When tissues are damaged, stem cells move in and produce new cells to replace the dying ones. As people get older, their stem cells gradually falter.
In the early 2000s, scientists realized that stem cells were not dying off in aging tissues.
"There were plenty of stem cells there," recalled Thomas A Rando, a professor of neurology at Stanford University School of Medicine. "They just don't get the right signals."
Rando and his colleagues wondered what signals the old stem cells would receive if they were bathed in young blood. To find out, they revived McCay's experiments.
The scientists joined old and young mice for five weeks and then examined them. The muscles of the old mice had healed about as quickly as those of the young mice, the scientists reported in 2005. In addition, the old mice had grown new liver cells at a youthful rate.
The young mice, on the other hand, had effectively grown prematurely old. Their muscles had healed more slowly, and their stem cells had not turned into new cells as quickly as they had before the procedure.
The experiment indicated that there were compounds in the blood of the young mice that could awaken old stem cells and rejuvenate aging tissue. Likewise, the blood of the old mice had compounds that dampened the resilience of the young mice.
Amy J Wagers, a member of Rando's team, continued to study the blood of young mice after she moved in 2004 to Harvard, where she is an associate professor. Last year, she and her colleagues demonstrated that it could rejuvenate the hearts of old mice.
To pinpoint the molecules responsible for the change, Wagers and her colleagues screened the animals' blood and found that a protein called GDF11 was abundant in young mice and scarce in old ones. To see if GDF11 was crucial to the parabiosis effect, the scientists produced a supply of the protein and injected it into old mice. Even on its own, GDF11 rejuvenated their hearts.
Wagers and her colleagues wondered whether GDF11 was responsible for the rejuvenation of other tissues. In the current issue of the journal Science, they report an experiment on skeletal muscle in mice. They found that GDF11 revived stem cells in old muscles, making old mice stronger and increasing their endurance.
At Stanford, researchers were investigating whether the blood of young mice altered the brains of old mice. In 2011, Saul Villeda, then a graduate student, and his colleagues reported that it did. When old mice received young blood, they had a burst of new neurons in the hippocampus, a region of the brain that is crucial for forming memories.
In a study published Sunday in the journal Nature Medicine, Villeda, now a faculty fellow at the University of California, San Francisco, and his colleagues unveiled more details of what young blood does to the brains of old mice.
After parabiosis, Villeda and his colleagues found that the neurons in the hippocampus of the old mice sprouted new connections. They then moved beyond parabiosis by removing the cells and platelets from the blood of young mice and injecting the plasma that remained into old mice. That injection caused the old mice to perform far better on memory tests.
Wagers' team has been investigating a specific region of the brain involved in perceiving smells.
In a second study in Science, the team reported that parabiosis spurred the growth of blood vessels in the brain. The new blood supply led to the growth of neurons and gave older mice a sharper sense of smell.
After linking the GDF11 protein to the rejuvenation of skeletal muscle and the heart, Wagers and her colleagues studied whether the protein was also responsible for the changes in the brain. They injected GDF11 alone into the mice and found that it spurred the growth of blood vessels and neurons in the brain, although the change was not as large as that from parabiosis.
"There's no conflict between the two groups, which is heartening," said Richard M Ransohoff, director of the Neuroinflammation Research Center at the Cleveland Clinic.
Ransohoff and others hope the experiments on mice will lead to studies on people to see if the human version of GDF11, or other molecules in the blood of young people, has a similar effect on older adults.
"We can turn back the clock instead of slowing the clock down," said Toren Finkel, director of the Center for Molecular Medicine at the National Heart, Lung and Blood Institute. "That's a nice thought if it pans out."
This reversal could occur throughout the body, the new research suggests. "Instead of taking a drug for your heart and a drug for your muscles and a drug for your brain, maybe you could come up with something that affected them all," Wagers said.
But scientists would need to take care in rejuvenating old body parts. Waking up stem cells might lead to their multiplying uncontrollably.
"It is quite possible that it will dramatically increase the incidence of cancer," said Irina M. Conboy, a professor of bioengineering at the University of California, Berkeley. "You have to be careful about overselling it."
5th May 2014, 12:12 PM #1073
Re: Health Bulletin
Swedish scientists want to test heart attack vaccine in India
Swedish scientists who have developed a vaccine that has shown tremendous promise against coronary artery diseases and strokes are keen to test it in India.
Atherosclerosis is a serious condition where arteries become clogged up by fatty substances, such as cholesterol called plaque. They cause arteries to harden and narrow thereby blocking the blood supply to the heart - triggering a heart attack or a stroke in the brain.
The vaccine prevents accumulation of the plaques.
Carani B Sanjeevi from the Karolinska Institute in Stockholm is now in final stage talks with Indian medical institutes to test the vaccine on Indians.
Sanjeevi from the Institute's department of medicine and advisor to its innovation office wants the vaccine to be specific to Indians who are known to be genetically prone to heart attack.
Speaking to TOI at the India Unlimited Festival organized by the Indian embassy in Sweden, Sanjeevi said "The trials of this highly promising vaccine may soon take place in India. We are in discussions with top medical institutes who will jointly develop the vaccine with Swedish researchers specifically for the Indian market. The vaccine stops plaque from building thereby cutting down on inflammation and ultimately preventing people from coronary artery disease."
As many as 45 million coronary artery disease cases were diagnosed in India in 2010 and the figure is expected to go up to 60 million by 2015.
Vaccination against the receptor that the T cells use to recognize bad LDL cholesterol can block the immune reaction and reduce the disease by 70%. The vaccine has been successfully tested on animals and the researchers are now hoping to see if it can be developed into a treatment for patients with a high risk of myocardial infarction and stroke.
A recent study by researchers at the Swedish medical university shows that the immune defence's T cells can attack the bad LDL cholesterol and thereby cause an inflammation that leads to atherosclerosis. By producing a vaccine against the T cell receptors, the researchers have managed to inhibit the development of atherosclerosis in animals.
Cholesterol is transported in the blood in LDL particles. LDL activates the immune defence and triggers an inflammation in the blood vessels that leads to atherosclerosis. When the atherosclerotic plaque finally ruptures, a blood clot is formed that in turn can cause a heart attack or stroke.
It was previously thought that the inflammation in the blood vessels arises when the T cells react to oxidized LDL particles located in the atherosclerotic plaque. The team at Karolinska Institute has found that the opposite is true, namely that the T cells react to components in the normal LDL particles and that they no longer recognize LDL once it has been oxidized.
"Since reactions to LDL can be dangerous, T cells are normally held in check by inhibitory signals," said Professor Goran K Hansson who led the study.
"The body's own control works well as long as the LDL keeps to the blood, liver and lymph glands. But when it accumulates in the artery wall, this inhibition is no longer enough, the T cells are activated and an inflammation arises," Hansson added.
According to the World Congress of Cardiology, it is estimated that by 2020 heart diseases will be the cause of over 40% in India as compared to 24% in 1990.
5th May 2014, 08:47 PM #1074
Re: Health Bulletin
Human fat can help treat brain cancer
Stem cells taken from a patient's own body fat could soon be used to treat deadly brain cancer, according to new research. Scientists have successfully used stem cells derived from human body fat to deliver biological treatments directly to the brains of mice with the most common and aggressive form of brain tumour, significantly extending their lives.
The experiments advance the possibility that the technique could work in people after surgical removal of brain cancers called glioblastomas to find and destroy any remaining cancer cells in difficult-to-reach areas of the brain, researchers said.
Glioblastoma cells are particularly nimble; they are able to migrate across the entire brain, hide out and establish new tumours. Cure rates for the tumour are notoriously low as a result, researchers said. In the mouse experiments, researchers used mesenchymal stem cells (MSCs) - which have an unexplained ability to seek out cancer and other damaged cells - that they harvested from human fat tissue.
They modified the MSCs to secrete bone morphogeneticprotein 4 (BMP4), a small protein involved in regulating embryonic development and known to have some tumour suppression function.
The researchers, who had already given a group of mice glioblastoma cells several weeks earlier, injected stem cells armed with BMP4 into their brains. Researchers said the mice treated this way had less tumour growth and spread, and their cancers were overall less aggressive and had fewer migratory cancer cells compared to mice that didn't get the treatment.
Meanwhile, the mice that received stem cells with BMP4 survived significantly longer, living an average of 76 days, as compared to 52 days in the untreated mice. "These modified mesenchymal stem cells are like a Trojan horse, in that they successfully make it to the tumour without being detected and then release their therapeutic contents to attack the cancer cells," said study leader Alfredo Quinones-Hinojosa, from the Johns Hopkins University School of Medicine.
Standard treatments for glioblastoma include chemotherapy, radiation and surgery, but even a combination of all three rarely leads to more than 18 months of survival after diagnosis.
Finding a way to get biologic therapy to mop up what other treatments can't get is a long-sought goal, said Quinones-Hinojosa, who cautions that years of additional studies are needed before human trials of fat-derived MSC therapies could begin.
The finding was published in the journal Clinical Cancer Research.
6th May 2014, 12:13 AM #1075
Re: Health Bulletin
New operation invented for complex Anal Fistulas
Dr Pankaj Garg, a senior colorectal surgeon from Panchkula, has invented a new operation for complex Anal Fistulas. The new operation, GARG PERFACT procedure (Proximal Fistulotomy, External Repositioning of Fistula tract and Curettage of Tracts) is a next generation procedure to manage this dreaded disease.
This new procedure has now been recognized by the biggest society of Colorectal surgeons in the world, AMERICAN Society of Colo-Rectal Surgeons (ASCRS). Dr Garg has been formally invited by this prestigious society to give a lecture and demonstration of his invention in Fort Lauderdale (Miami), Florida, USA on 21 May, 2014. This meeting would be attended by over 7000 renowned surgeons from all over the world.
This is a big honor for the country as only 4 new operations have been invented across the globe for this complex disease in the last 50 years. And this is only the second time in the last six decades that this prominent American society has invited a non- American to demonstrate a new Fistula procedure.
After conventional operation for complex anal fistula, there is a big wound, a lot of pain, significant risk of incontinence (losing control over bowel motions), requires bed rest for 10-25 days and 30-40% risk of recurrence (the disease coming back). However, after the Garg PERFACT procedure, there is no/minimal wound, no risk of incontinence ( the sphincter is not cut at all), the patient is sent home the same or the very next day of operation and the patient can resume all normal activities thereafter. This includes walking upto 5 kms, jogging, running, climbing stairs etc. The success rate of this procedure is also more than 90% (recurrence rate less than 10%).
6th May 2014, 02:28 PM #1076
Re: Health Bulletin
Forget brain, wiring in your retina detect motion first
Making sense of at which direction and at what speed a car is moving may not be possible without the interpretation of the brain, but processing of some of these information starts right at the retinas of the eyes.
Researchers have now explained how the various types of cells in the retina are wired to help the eyes detect the direction and speed of moving objects.
"The wiring diagram represents only a tiny proportion of the total number of connections on the retina," said Sebastian Seung, a computational neuro scientist at Massachusetts Institute of Technology in the US.
To understand how cells are wired together in the retina, the researchers analysed high-resolution electron microscope images of a mouse retina with the help of nearly 2,200 members of EyeWire, an online 'citizen-science' game set up to help with brain-mapping efforts.
Players traced the pathways through the layers of cells to create a high-resolution wiring diagram of part of the retina.
The reconstructed map showed that while one type of bipolar cell (that transmit signals from the photoreceptors to the ganglion cells) connects to the amacrine cells (responsible for 70 percent of input to retinal ganglion cells) filaments close to the cell body, another does do so farther away along the length of the filaments.
The bipolar cells that connect closer to the starburst amacrine cell bodies are known to relay their messages with a time delay, whereas the others transmit their immediately, the researchers discovered.
Because of the lag in the first type of connection, signals that hit two nearby locations on the retina at two slightly different times - as would happen when an object moves across the visual field - could reach the same amacrine-cell filament at the same time.
According to the researchers, the following could help explain how the retina detects motion: The amacrine cell might fire only when it receives this combined information, signalling that something is moving in the direction of the filament.
Stimuli not moving in the direction of the filament would produce impulses that reach the amacrine cell at different times, so that it would not fire.
The study appeared in the journal Nature.
6th May 2014, 08:14 PM #1077
Re: Health Bulletin
Anger, anxiety and depression may lead to a heart attack: study
Anger, anxiety and depression not only affect the functioning of the heart, but also increase the risk for heart disease, scientists have warned. Stroke and heart attacks are the end products of progressive damage to blood vessels supplying the heart and brain, a process called atherosclerosis.
Atherosclerosis progresses when there are high levels of chemicals in the body called pro-inflammatory cytokines.
It is thought that persisting stress increases the risk for atherosclerosis and cardiovascular disease by evoking negative emotions that, in turn, raise the levels of pro-inflammatory chemicals in the body. Researchers have now investigated the underlying neural circuitry of this process.
"Drawing upon the observation that many of the same brain areas involved in emotion are also involved in sensing and regulating levels of inflammation in the body, we hypothesised that brain activity linked to negative emotions - specifically efforts to regulate negative emotions - would relate to physical signs of risk for heart disease," said Dr Peter Gianaros, Associate Professor at the University of Pittsburgh and first author on the study.
Gianaros and his colleagues recruited 157 healthy adult volunteers who were asked to regulate their emotional reactions to unpleasant pictures while their brain activity was measured with functional imaging. Researchers also scanned their arteries for signs of atherosclerosis to assess heart disease risk and measured levels of inflammation in the bloodstream, a major physiological risk factor for atherosclerosis and premature death by heart disease.
They found that individuals who show greater brain activation when regulating their negative emotions also exhibit elevated blood levels of interleukin-6, one of the body's pro-inflammatory cytokines, and increased thickness of the carotid artery wall, a marker of atherosclerosis. The inflammation levels accounted for the link between signs of atherosclerosis and brain activity patterns seen during emotion regulation. "These new findings agree with the popular belief that emotions are connected to heart health," said Gianaros.
"We think that the mechanistic basis for this connection may lie in the functioning of brain regions important for regulating both emotion and inflammation.
"These findings may have implications for brain-based prevention and intervention efforts to improve heart health and protect against heart disease," said Gianaros.
The study was published in the journal Biological Psychiatry.
6th May 2014, 08:17 PM #1078
Re: Health Bulletin
How to minimize risk of skin cancer in summers
Scientists have revealed that sun tanning equals skin damage and teens should take special care in summer to minimize the risk of skin cancer.
Dr. David R. Byrd, director of surgery at Seattle Cancer Care Alliance and professor at the University of Washington School of Medicine, said that as it only takes a few bad sunburns or trips to the tanning bed to put someone at risk for melanoma, people should use a daily sunscreen with an SPF of 30 and limit the amount of time spent in the sun between the hours of 10 a.m. and 4 p.m.
The researchers found that teens choosing to tan indoors under UV light are more likely to get melanoma and 76 percent of melanomas found in women between the ages of 18 and 29 are associated with tanning bed use.
According to the study, only 15 percent of males and 37 percent of females claim to use sunscreen most of the time or always.
7th May 2014, 12:38 AM #1079
Re: Health Bulletin
Being born 4-6 weeks premature can affect the brain
Scientists have found that brains of children who were born just a few weeks early differ from those born on time, and these differences may affect learning and behaviour.
Studies have shown that children who were born between 34 and 36 weeks' gestation (late preterm) have more social, behavioural and academic problems than children born at full term (37-41 weeks).
However, few studies have looked at the brain structure of late preterm children.
Researchers from the University of Iowa conducted magnetic resonance imaging (MRI) scans on 32 children ages 7-13 years old who were born at 34-36 weeks' gestation.
In addition, they administered cognitive tests to the children while parents completed a behavioural assessment.
Results were compared to 64 children born at full term who were recruited for another study in which they completed the same cognitive and behavioural assessments, neurological exam, and MRI sequences as the late preterm group.
Preliminary analysis showed differences in both cognitive function and brain structure in the late preterm children compared to full term children.
Functionally, late preterm children had more difficulties with visuospatial reasoning and visual memory. They also had slower processing speed.
Processing speed refers to the ability to perform automatically a simple task in an efficient manner. Children with slower processing speed may require more time in the classroom setting to accomplish a task.
Structurally, the brains of late preterm children had less total cerebral white matter, which is critical to communication between nerve cells, and smaller thalami, a brain region involved in sensory and motor signalling.
"Late preterm birth accounts for 8 per cent of all births each year in the United States, making it a public health issue," said Jane E Brumbaugh from the University of Iowa Stead Family Department of Pediatrics.
"The effects of late preterm birth on the brain have not yet been fully characterised, and it has been assumed that there are no significant consequences to being born a few weeks early.
"Our preliminary findings show that children born late preterm have differences in brain structure and deficits in specific cognitive skills compared to children born full term," Brumbaugh said.
Parents of late preterm children also reported more problems with hyperactivity, inattention, opposition and aggression than parents of full term children.
The study was presented at the Pediatric Academic Societies (PAS) annual meeting in Vancouver, British Columbia, Canada.
7th May 2014, 03:48 PM #1080
Re: Health Bulletin
Maternal deaths falling, but not fast enough: WHO
Global maternal deaths have fallen sharply in recent decades, but women in sub-Saharan Africa are still by far the most likely to perish while pregnant, the World Health Organization said Tuesday.
Fresh WHO statistics show the number of maternal deaths worldwide fell to 289,000 last year, down 45 percent from 1990, when an estimated 523,000 women died during pregnancy or childbirth.
While this marks a big step forward, the UN's health agency stressed it was far from good enough.
"There is still one woman dying every one and a half to two minutes somewhere in the world ... because she is trying to give life," said Marleen Temmerman, who heads the WHO's department of reproductive health and co-authored the report.
"That is like having two airplanes crashing every day," she told reporters in Geneva, insisting "this should be much higher on the agenda".
The WHO report emphasises that the dangers of childbearing are still felt far more acutely in the developing world, and in sub-Saharan Africa especially, than in wealthy countries.
While a woman in Chad faces a one in 15 risk of dying during pregnancy and childbirth during her lifetime, the risk is more than 1,000 times smaller for a woman in Finland, the statistics show.
African nations are heavily represented among the 10 countries that account for around 60 percent of all maternal deaths globally, including Nigeria, Democratic Republic of Congo, Ethiopia and Kenya.
Several African nations meanwhile also figure among those who had succeeded in slashing their maternal mortality rates the most in the past 23 years, WHO said.
Rwanda, Equatorial Guinea and Eritrea were among a select group of only 11 countries, mainly in Asia, that have reduced maternal deaths by over 75 percent since 1990, thus reaching the Millennium Development Goal target ahead of the 2015 deadline.
US mortality rates jump
Most countries however are unlikely to meet that target by next year, Temmerman said, calling for far more investment in care for expecting mothers.
Expanding family planning and access to contraception is also vital to help avoid unwanted pregnancies, especially among teens, at far greater risk of complications.
The new WHO report provides a startling new overview of the reasons women die during pregnancy and childbirth.
It shows that 28 percent of the deaths are linked to pre-existing medical conditions, like diabetes, malaria, HIV or obesity, exacerbated by pregnancy.
Severe bleeding, mainly during and after childbirth, is the second leading cause,accounting for 27 percent of the deaths, the report shows.
"Integrated care for women with conditions like diabetes and obesity will reduce deaths and prevent long-lasting health problems," Temmerman said.
A number of wealthy countries have seen an increase in maternal mortality rates, with the rate in the United States for instance jumping 136 percent to 28 deaths for 100,000 live births last year.
In Canada, the number of deaths also shot up 81 percent to 11 deaths for 100,000 live births in 2013.
The report did not provide an explanation for the hikes, but WHO scientist Colin Mathers stressed such countries had started off with low numbers so the statistical changes were not as significant, and were likely largely explained by improved reporting methods for maternal deaths.
Temmerman hinted though that women waiting longer and having children in wealthy nations might explain some increases in maternal deaths.
"Older age in pregnant women contributes to a higher risk for diabetes, and more hypertension-related problems," she said, pointing out that "there are issues with being pregnant too young, but also being pregnant too old."