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www.sciencedaily.com

Pushing new frontiers in dementia research, Nanyang Technological University, Singapore (NTU Singapore) scientists have found a new way to treat dementia by sending electrical impulses to specific areas of the brain to enhance the growth of new brain cells.

Known as deep brain stimulation, it is a therapeutic procedure that is already used in some parts of the world to treat various neurological conditions such as tremors or Dystonia, which is characterised by involuntary muscle contractions and spasms.

NTU scientists have discovered that deep brain stimulation could also be used to enhance the growth of brain cells which mitigates the harmful effects of dementia-related conditions and improves short and long-term memory.

Their research has shown that new brain cells, or neurons, can be formed by stimulating the front part of the brain which is involved in memory retention using minute amounts of electricity.

The increase in brain cells reduces anxiety and depression, and promotes improved learning, and boosts overall memory formation and retention.

The research findings open new opportunities for developing novel treatment solutions for patients suffering from memory loss due to dementia-related conditions such as Alzheimer's and even Parkinson's disease.

This discovery was published in eLife, a peer-reviewed open-access scientific journal published by the Howard Hughes Medical Institute, the Max Planck Society and the Wellcome Trust.

Assistant Professor Ajai Vyas from NTU's School of Biological Sciences said, "The findings from the research clearly show the potential of enhancing the growth of brain cells using deep brain stimulation.

"Around 60 per cent of patients do not respond to regular anti-depressant treatments and our research opens new doors for more effective treatment options."

Dr Lim Lee Wei, an associate professor at Sunway University, Malaysia, who worked on the research project while he was a Lee Kuan Yew Research Fellow at NTU, said that deep brain stimulation brings multiple benefits.

"No negative effects have been reported in such prefrontal cortex stimulation in humans and studies have shown that stimulation also produces anti-depression effects and reduces anxiety.

"Memory loss in older people is not only a serious and widespread problem, but signifies a key symptom of dementia. At least one in 10 people aged 60 and above in Singapore suffer from dementia and this breakthrough could pave the way towards improved treatments for patients."

Growing new brain cells

For decades, scientists have been finding ways to generate brain cells to boost memory and learning, but more importantly, to also treat brain trauma and injury, and age-related diseases such as dementia.

As part of a natural cycle, brain cells constantly die and get replaced by new ones. The area of the brain responsible for generating new brain cells is known as the hippocampus, which is also involved in memory forming, organising and retention.

By stimulating the front part of the brain known as the prefrontal cortex, new brain cells are formed in the hippocampus although it had not been directly stimulated.

The research was conducted using middle-aged rats, where electrodes which sends out minute micro-electrical impulses were implanted in the brains. The rats underwent a few memory tests before and after stimulation, and displayed positive results in memory retention, even after 24 hours.

"Extensive studies have shown that rats' brains and memory systems are very similar to humans," said Prof Ajai who is a recipient of NTU's prestigious Nanyang Assistant Professorship award.

"The electrodes are harmless to the rats, as they go on to live normally and fulfil their regular (adult) lifespan of around 22 months."

The research was funded by the Lee Kuan Yew Research Fellowship which supports and promotes young and outstanding researchers in their respective areas of specialisation.

JESSICA FIRGER

Scientists have discovered a highly aggressive new strain of HIV in Cuba that develops into full-blown AIDS three times faster than more common strains of the virus. This finding could have serious public health implications for efforts to contain and reduce incidences of the virus worldwide.

Researchers at the University of Leuven in Belgium say the HIV strain CRF19 can progress to full blown AIDS within two to three years of exposure to virus. Typically, HIV takes approximately 10 years to develop into AIDS. Patients with CRF19 may start getting sick before they even know they've been infected, which ultimately means there's a significantly shorter time span to stop the disease's progression. 

The scientists began studying the cases in Cuba when reports began coming in that a growing number of HIV-infected patients were developing AIDS just three years after diagnosis with the virus. The findings of their study were published in the journal EBioMedicine.

Having unprotected sex with multiple partners can expose a person to numerous strains of the HIV virus. Research has found that when this occurs, the different strains can combine and form a new variant of the virus.

When HIV first enters the human body it latches on to anchor points of a certain protein, known as CCR5 on the cell membranes, which then allows it to enter human cells. Eventually the virus then latches onto another protein of the cell membrane, known as CXCR4. This marks the point when asymptomatic HIV becomes AIDS. In CRF19, the virus makes this move much sooner. 

For the study, the researchers analyzed blood samples of 73 recently infected patients. Among the group, 52 already had full-blown AIDS, while the remaining 21 were HIV-positive but the virus had not yet progressed. The researchers compared their findings to blood samples of 22 AIDS patients who had more common strains of the virus. 

The researchers found that patients with CRF19 had higher levels of the virus in their blood compared with those who had more common strains. 

They also had higher levels of the immune response molecules known as RANTES, which bond to CCR5 proteins in early stages of the virus. The abnormally high level of RANTES in patients infected with the new strain indicates that the virus runs out of CCR5 anchor points much earlier and moves directly to CXCR4 anchor points.

Thanks to advances in medical treatment and the development of highly effective antiretroviral drugs, HIV/AIDS is no longer a death sentence. But the researchers caution that patients with the new strain of the virus are more likely to be diagnosed when they already have full-blown AIDS and when damage from the disease has taken a toll.

The researchers suspect that this aggressive form of HIV occurs when fragments of other subsets of the virus cling to each other through an enzyme that makes the virus more powerful and easily replicated in the body.

There are currently 35 million people worldwide living with HIV/AIDS, according to the most recent data from the World Health Organization. Scientists have identified more than 60 different strains of the HIV 1 virus, with each type typically found predominantly in a specific region of the world.

Source: www.cbsnews.com

While debate about recreational marijuana use continues, researchers are investigating the effectiveness of cannabis for treating pain, spasticity, and a host of other medical problems. In a symposium organized by the McGill University Health Centre (MUHC) as part of the 2015 American Association for the Advancement of Science Annual Meeting held this week in San Jose, California,  experts from North America and the U.K. share their perspectives on the therapeutic potential of medical cannabis and explore the emerging science behind it.

"We need to advance our understanding of the role of cannabinoids in health and disease through research and education for patients, physicians and policy-makers," says Dr. Mark Ware, director of clinical research at the Alan Edwards Pain Management Unit at the MUHC, in Canada.

As a pain specialist Dr. Ware regularly sees patients with severe chronic pain at his clinic in Montreal, and for some of them, marijuana appears to be a credible option. "I don't think that every physician should prescribe medical cannabis, or that every patient can benefit but it's time to enhance our scientific knowledge base and have informed discussions with patients."

Increasing numbers of jurisdictions worldwide are allowing access to herbal cannabis, and a range of policy initiatives are emerging to regulate its production, distribution, and authorization. It is widely believed that there is little evidence to support the consideration of cannabis as a therapeutic agent. However, several medicines based on tetrahydrocannabinol (THC), the psychoactive ingredient of cannabis, have been approved as pharmaceutical drugs.

Leading British cannabis researcher Professor Roger Pertwee, who co-discovered the presence of tetrahydrocannabivarin (THCV) in cannabis in the 70's, recently published with collaborators some findings of potential therapeutic relevance in the British Journal of Pharmacology. "We observed that THCV, the non-psychoactive component of cannabis, produces anti-schizophrenic effects in a preclinical model of schizophrenia," says Pertwee, professor of Neuropharmacology at Aberdeen University. "This finding has revealed a new potential therapeutic use for this compound."

Neuropsychiatrist and Director of the Center for Medicinal Cannabis Research (CMCR) at the University of California, San Diego Dr. Igor Grant is interested in the short and long-term neuropsychiatric effects of marijuana use. The CMCR has overseen some of the most extensive research on the therapeutic effects of medical marijuana in the U.S. "Despite a commonly held view that cannabis use results in brain damage, meta analyses of extensive neurocognitive studies fail to demonstrate meaningful cognitive declines among recreational users," says Dr. Grant. "Bain imaging has produced variable results, with the best designed studies showing null findings."

Dr. Grant adds that while it is plausible to hypothesize that cannabis exposure in children and adolescents could impair brain development or predispose to mental illness, data from properly designed prospective studies is lacking.

Source: www.sciencedaily.com

Eve, an artificially-intelligent 'robot scientist' could make drug discovery faster and much cheaper, say researchers writing in the Royal Society journal Interface. The team has demonstrated the success of the approach as Eve discovered that a compound shown to have anti-cancer properties might also be used in the fight against malaria.

Robot scientists are a natural extension of the trend of increased involvement of automation in science. They can automatically develop and test hypotheses to explain observations, run experiments using laboratory robotics, interpret the results to amend their hypotheses, and then repeat the cycle, automating high-throughput hypothesis-led research. Robot scientists are also well suited to recording scientific knowledge: as the experiments are conceived and executed automatically by computer, it is possible to completely capture and digitally curate all aspects of the scientific process.

In 2009, Adam, a robot scientist developed by researchers at the Universities of Aberystwyth and Cambridge, became the first machine to independently discover new scientific knowledge. The same team has now developed Eve, based at the University of Manchester, whose purpose is to speed up the drug discovery process and make it more economical. In the study published today, they describe how the robot can help identify promising new drug candidates for malaria and neglected tropical diseases such as African sleeping sickness and Chagas' disease.

"Neglected tropical diseases are a scourge of humanity, infecting hundreds of millions of people, and killing millions of people every year," says Professor Steve Oliver from the Cambridge Systems Biology Centre and the Department of Biochemistry at the University of Cambridge. "We know what causes these diseases and that we can, in theory, attack the parasites that cause them using small molecule drugs. But the cost and speed of drug discovery and the economic return make them unattractive to the pharmaceutical industry.

"Eve exploits its artificial intelligence to learn from early successes in her screens and select compounds that have a high probability of being active against the chosen drug target. A smart screening system, based on genetically engineered yeast, is used. This allows Eve to exclude compounds that are toxic to cells and select those that block the action of the parasite protein while leaving any equivalent human protein unscathed. This reduces the costs, uncertainty, and time involved in drug screening, and has the potential to improve the lives of millions of people worldwide."

Eve is designed to automate early-stage drug design. First, she systematically tests each member from a large set of compounds in the standard brute-force way of conventional mass screening. The compounds are screened against assays (tests) designed to be automatically engineered, and can be generated much faster and more cheaply than the bespoke assays that are currently standard. This enables more types of assay to be applied, more efficient use of screening facilities to be made, and thereby increases the probability of a discovery within a given budget.

Eve's robotic system is capable of screening over 10,000 compounds per day. However, while simple to automate, mass screening is still relatively slow and wasteful of resources as every compound in the library is tested. It is also unintelligent, as it makes no use of what is learnt during screening.

To improve this process, Eve selects at random a subset of the library to find compounds that pass the first assay; any 'hits' are re-tested multiple times to reduce the probability of false positives. Taking this set of confirmed hits, Eve uses statistics and machine learning to predict new structures that might score better against the assays. Although she currently does not have the ability to synthesise such compounds, future versions of the robot could potentially incorporate this feature.

Professor Ross King, from the Manchester Institute of Biotechnology at the University of Manchester, says: "Every industry now benefits from automation and science is no exception. Bringing in machine learning to make this process intelligent -- rather than just a 'brute force' approach -- could greatly speed up scientific progress and potentially reap huge rewards."

To test the viability of the approach, the researchers developed assays targeting key molecules from parasites responsible for diseases such as malaria, Chagas' disease and schistosomiasis and tested against these a library of approximately 1,500 clinically approved compounds. Through this, Eve showed that a compound that has previously been investigated as an anti-cancer drug inhibits a key molecule known as DHFR in the malaria parasite. Drugs that inhibit this molecule are currently routinely used to protect against malaria, and are given to over a million children; however, the emergence of strains of parasites resistant to existing drugs means that the search for new drugs is becoming increasingly more urgent.

"Despite extensive efforts, no one has been able to find a new antimalarial that targets DHFR and is able to pass clinical trials," adds Professor King. "Eve's discovery could be even more significant than just demonstrating a new approach to drug discovery."

The research was supported by the Biotechnology & Biological Sciences Research Council and the European Commission.

Source: www.sciencedaily.com

By Catharine Paddock PhD

The rise of drug-resistant bacteria - such as MRSA - is making it increasingly difficult to control even common infections like pneumonia or urinary tract infections with standard antibiotics. After repeated exposure, the bugs mutate into strains that are immune to the drugs that once killed them.

There is clearly a desperate need for new drugs to fight these superbugs. But there is also another option - to extend the useful life of a drug. Now, researchers have developed a computer algorithm that can help in this area.

Imagine the war against a superbug as a chess game, with each move that your opponent makes being a mutation in the superbug that makes it more drug-resistant. 

To stand a good chance of winning, it helps to anticipate your opponent's most likely counter-moves.

Now, a team of researchers - including members from Duke University in Durham, NC - has developed a computer algorithm that stands a good chance of beating a superbug at its own game.

The software - called OSPREY - predicts the most likely mutations that a bug develops in response to a new drug before the drug is even given to patients.

Writing in the Proceedings of the National Academy of Sciences, the team describes how they tested OSPREY with the superbug MRSA (methicillin-resistant Staphylococcus aureus). 

The researchers programmed the algorithm to identify the genetic changes that MRSA would have to undergo in order to become resistant to a promising new class of experimental drug. And when they exposed MRSA to the new drugs, they found some of the genetic changes the software had predicted actually arose.

"This gives us a window into the future to see what bacteria will do to evade drugs that we design before a drug is deployed," says author Bruce Donald, a professor of computer science and biochemistry at Duke.

The team hopes the approach they are developing will give drug designers a head start in the race against superbugs, as co-author and Duke graduate student Pablo Gainza-Cirauqui explains:

"If we can somehow predict how bacteria might respond to a particular drug ahead of time, we can change the drug, or plan for the next one, or rule out therapies that are unlikely to remain effective for long."

Resistant forms of Staphylococcus aureus now kill 11,000 people in the US every year - more than HIV. In 1975, around 2% of infections caused by the bacterium were resistant to treatment - rising to 29% in 1991 - and now the proportion is 55%.

Depending on the drug, it can take up to 20 years for resistant strains to emerge. Sometimes it only takes 1 year.

Ability to anticipate new mutations beats searching 'libraries' of known mutations

The team believes approaches like OSPREY beat the current method where scientists have to look up "libraries" of previously observed resistance mutations - an approach that is not necessarily satisfactory for predicting future mutations. Prof. Donald explains:

"With a new drug, there is always the possibility that the organism will develop different mutations that had never been seen before. This is what really worries physicians."

OSPREY - which stands for Open Source Protein REdesign for You - is based on a protein design algorithm. It identifies changes to DNA sequences in the bacteria that would enable the resulting protein to block the drug while still being able to work normally.

The team tested OSPREY with a new class of drugs called propargyl-linked antifolates that attack a bacterial enzyme called dihydrofolate reductase (DHFR), used for building DNA and other tasks. The drugs - still to be tested in humans - are showing promise as a new treatment for MRSA infections.

Using OSPREY, the team came up with a ranked list of possible mutations. They picked out four - none of which had been seen before.

One predicted mutation reduced drug effectiveness by 58%

When they treated MRSA with the new drugs, they found more than half of the bacteria that survived carried the mutation they predicted would give the organism the greatest amount of resistance: a tiny change in the bacterial DNA that reduced the effectiveness of the new drugs by 58%.

"The fact that we actually found the new predicted mutations in bacteria is very exciting," Prof. Donald says, adding that the approach could be expanded to anticipate the bug's responses more than one move ahead:

"We might even be able to coax a pathogen into developing mutations that enable it to evade one drug, but that then make it particularly susceptible to a second drug, like a one-two punch."

The team is now enhancing OSPREY to predict resistance mutations to drugs designed to treat E. coli and Enterococcus infections.

They believe OSPREY will be useful for predicting drug resistance in cancer, HIV, flu and other diseases where culturing resistant strains is harder than it is with bacteria.

Prof. Donald and colleagues are developing OSPREY in open source format so it is freely available for any researcher to use.

In September 2014, Medical News Today learned about a study that showed how an  old drug may lead to a potential new class of antibiotics . The study showed that lamotrigine - currently used as an anticonvulsant - can inhibit the assembly of ribosomes in bacteria.

Source: www.medicalnewstoday.com

Jenna Birch

While cancer can strike anyone — young or old, unhealthy and healthy — we do have some idea of what can affect risk. Genetics often play a role, for instance, as do lifestyle habits. But according to a new study from Johns Hopkins University researchers, much of cancer risk may actually be due to mere chance.

Cancer develops when stem cells of a given tissue make random mistakes, mutating unchecked after one chemical letter of DNA is incorrectly swapped for another — the equivalent of a cell “oops.” It happens without warning, like the body’s roll of the die. 

For the new study, published in the journal Science, researchers wanted to see how much of overall cancer risk was due to these unpreventable random mutations, independent of other factors like heredity and lifestyle. 

“There is this question that is fundamental in cancer research: How much of cancer is due to environmental factors, and how much is due to inherited factors?” Cristian Tomasetti, PhD, a biomathematician and assistant professor of oncology at the Johns Hopkins University School of Medicine and Bloomberg School of Public Health, tells Yahoo Health. “To answer that question, however, the idea came that it would be important to determine first how much of cancer was simply due to ‘replicative chance.’"

To measure this, the researchers plotted the number of stem cell divisions in 31 types of tissues over the course of a lifetime against the lifetime risk of developing cancer in the given tissue. From this chart, the scientists were able to see the correlation between number of divisions and cancer risk — and from that correlation, researchers were able to determine the incidence of cancer in a given tissue due to replicative chance.

Ultimately, researchers found that roughly two-thirds of the cancer incidence was due to this replicative chance, or simply “bad luck.” (However, it’s worth noting researchers did not examine some cancers, such as breast and prostate cancers, because of lack of reliable stem-cell turnover information.)

But don’t assume you’re simply doomed to the hand fate deals you. After additional analysis, researchers found that of the 31 cancers examined, 22 could be explained by “bad luck” — but for the other nine, there was another factor aside from simple chance that likely contributed to the cancer.

This is presumably because environmental and hereditary factors play a role in development. “There are many cancers where primary prevention has huge positive effects, such as vaccines against infectious agents, quitting smoking or other altered lifestyles,” says Tomasetti. 

Incidentally, the cancers where risk could be lowered by primary preventive practices were ones you may expect — diseases like skin cancer, where limiting sun exposure can lower your risk, as well as lung cancer, where avoiding smoking is key. 

Source: www.yahoo.com

By Catharine Paddock PhD

At present, diagnosis of lung cancer relies on an invasive biopsy that is only effective after tumors are bigger than 3 cm or even metastatic. Earlier detection would vastly improve patients' chances of survival. Now a team of researchers is developing a "lab-on-a-chip" that promises to detect lung cancer - and possibly other deadly cancers - much earlier, using only a small drop of a patient's blood.

In the Royal Society of Chemistry journal, Yong Zeng, assistant professor of chemistry at the University of Kansas, and colleagues report a breakthrough study describing their invention.

For some time, scientists have been excited by the idea of testing for disease biomarkers in "exosomes" - tiny vesicles or bags of molecules that cells, including cancer cells - release now and again. When they first spotted them, researchers thought exosomes were just for getting rid of cell waste, but now they know they also do other important things such as carry messages to other cells near and far.

The challenge, however, is developing a technology that is small enough to target and analyze the contents of exosomes - mostly nucleic acids and proteins - to find unique biomarkers of disease. This is because exosomes are tiny - around 30 to 150 nanometers (nm) in diameter - much smaller, for example, than red blood cells.

Current methods for separating out and testing exosomes require several steps of ultracentrifugation - a lengthy and inefficient lab procedure, as Prof. Zeng explains:

"There aren't many technologies out there that are suitable for efficient isolation and sensitive molecular profiling of exosomes. First, current exosome isolation protocols are time-consuming and difficult to standardize. Second, conventional downstream analyses on collected exosomes are slow and require large samples, which is a key setback in clinical development of exosomal biomarkers."

Now, using microfluid technology, he and his colleagues have developed a lab-on-a-chip that can analyze the contents of targeted exosomes and spot the early signs of deadly cancer. They have already successfully tested it on lung cancer.

Lab-on-a-chip device uses smaller samples, is faster, cheaper and more sensitive

The new device, which uses much smaller samples, promises to produce results faster, more cheaply, with better sensitivity compared to conventional benchtop instruments, as Prof. Zeng continues to explain:

"A lab-on-a-chip shrinks the pipettes, test tubes and analysis instruments of a modern chemistry lab onto a microchip-sized wafer."

The technology behind the device - known as microfluidics - came out of new semiconductor electronics and has been under intensive development since the 1990s, he adds:

"Essentially, it allows precise manipulation of minuscule fluid volumes down to one trillionth of a liter or less to carry out multiple laboratory functions, such as sample purification, running of chemical and biological reactions, and analytical measurement."

Unlike breast and colon cancer, there is no widely accepted screening tool for lung cancer, which in most cases is first diagnosed based on symptoms that normally indicate lung function is already impaired.

To diagnose lung cancer, doctors have to perform a biopsy - remove a piece of tissue from the lung and send it to a lab for molecular analysis. It is rarely possible to do this in the early stages as tumors are too small to be spotted on scans.

"In contrast, our blood-based test is minimally invasive, inexpensive, and more sensitive, thus suitable for large population screening to detect early-stage tumors," says Prof. Zeng, adding that the technique offers a general platform for detecting exosomes from cancer cells. The team has already used the device to test for ovarian cancer, and in theory, says Prof. Zeng, it should also be applicable to other cancer types.

"Our long-term goal is to translate this technology into clinical investigation of the pathological implication of exosomes in tumor development. Such knowledge would help develop better predictive biomarkers and more efficient targeted therapy to improve the clinical outcome," he adds.

The team has received further funding from the National Cancer Institute at the National Institutes of Health to further develop the lab-on-a-chip.

In March 2013, Medical News Today learned how another team of scientists is developing a lab-on-a-chip that is implanted under the skin to track levels of substances in the blood and transmit the results wirelessly to a smartphone or other receiving device.

Source: www.medicalnewstoday.com

By LAWRENCE K. ALTMAN

A British-American scientist and a pair of Norwegian researchers were awarded this year’s Nobel Prize in Physiology or Medicine on Monday for discovering “an inner GPS, in the brain,” that makes navigation possible for virtually all creatures.

John O’Keefe, 75, a British-American scientist, will share half of the prize of 8 million kronor, or $1.1 million, in what is considered the most prestigious scientific award. May-Britt Moser, 51, and Edvard I. Moser, 52, who are married, will share the other half, said the Karolinska Institute in Sweden, which chooses the laureates.

The three scientists’ discoveries “have solved a problem that has occupied philosophers and scientists for centuries — how does the brain create a map of the space surrounding us and how can we navigate our way through a complex environment,” the institute said in a news release.

The positioning system in the brain that they discovered helps us know where we are, find our way from place to place and store the information for the next time, said Goran K. Hansson, secretary of the Karolinska’s Nobel Committee, in announcing the laureates.

The researchers documented that certain cells are responsible for higher cognitive function that steers the navigational system, the committee said.

Dr. O’Keefe began using neurophysiological methods in the late 1960s to study how the brain controls behavior. In 1971 he discovered the first component of the inner navigational system in rats. He identified nerve cells in the hippocampus region of the brain that were always activated when a rat was at a certain location. He called them “place cells” and showed that the cells registered not only what they saw, but also what they did not see, by building up inner maps in different environments.

Dr. O’Keefe was born in New York City and graduated from the City College of New York. He earned a Ph.D. in physiological psychology at McGill University in Montreal, in 1967, and moved for postdoctoral training to University College London, where he remains. He is a professor of cognitive neuroscience.

In 2005, the Mosers discovered a second crucial component of the brain’s positioning system by identifying another type of nerve cell that permits coordination and positioning. The scientists, who work at the Norwegian University of Science and Technology in Trondheim, called the cells grid cells. While mapping connections to the hippocampus in rats moving about a room in a laboratory, “they discovered an astonishing pattern of activity in a nearby part of the brain called the entorhinal cortex,” the Nobel committee said.

When the rat passed multiple locations, the cells formed a hexagonal grid. Each cell activated in unique spatial patterns. Their research showed “how both ‘place’ and ‘grid’ cells make it possible to determine position and to navigate,” the committee said.

The Mosers grew up in rural Norway and came from nonacademic families. May-Britt was born in Fosnavag and Edvard in Alesund. Although they went to the same high school, they did not know each other well until they were undergraduates at the University of Oslo. They married while they were college students and have two daughters. Both are professors at the university in Trondheim.

At one point they were visiting scientists at University College London, studying under Dr. O’Keefe.

The three also won Columbia University’s Louisa Gross Horwitz Prize last year for their discoveries.

Only a handful of married couples have shared a Nobel Prize, and the Mosers are only the second in the medicine category, which has been awarded since 1901. Fewer than a dozen women have been named laureates in medicine.

Evidence that place and grid cells exist in humans comes from recent studies using brain imaging techniques and from patients who have undergone neurosurgery.

The laureates’ findings may eventually lead to a better understanding of the spatial losses that occur in Alzheimer’s and other neurological diseases. The hippocampus and entorhinal cortex are often damaged in early stages of Alzheimer’s, with affected individuals’ losing their way and failing to recognize the environment. The findings also open new avenues for understanding cognitive processes like memory, thinking and planning, the Nobel Committee said.

According to The Associated Press, May-Britt Moser said the couple was elated. “This is such a great honor for all of us and all the people who have worked with us and supported us,” she said in a telephone interview with The A.P. “We are going to continue and hopefully do even more groundbreaking work in the future.”

Her husband was flying when the prize was announced, she said, and he later told the Norwegian news agency NTB that he learned about it when he landed and turned on his cellphone, to a barrage of messages and calls. “I didn’t know anything. When I got off the plane there was a representative there with a bouquet of flowers who said ‘congratulations on the prize,’   ” The Associated Press reported.

The laureates traditionally receive their awards at a banquet in Stockholm on Dec. 10, the anniversary of the death in 1896 of the prize’s creator, Alfred Nobel, an industrialist and inventor of dynamite.

Source: http://www.nytimes.com

By Ian Lee

 Far from the sea, a man-made coral reef is taking shape -- and it could change medical operations forever.

Step inside the OkCoral lab in Israel's Negev Desert and you'll find row after row of quietly bubbling fish tanks, each containing a precious substance.

It is hoped the coral grown in this surreal "farm," could one day be used in bone operations -- encompassing everything from dental implants to spinal procedures.

Unlike animal and human bones, coral can't be rejected by the body, say medical experts at the company CoreBone, which manufactures bone replacements from coral.

Grown in the lab, this coral is also free from the diseases you might find in the oceanic variety.

Start-up science

Assaf Shaham founded the unusual laboratory six years ago at a cost of $2.5 million, with an ambitious vision of tapping into the billion dollar worldwide bone grafting industry.

But first he'll need the approval of authorities in the European Union and U.S., with a decision expected next year.

The father-of-two's dedication to the business is astounding -- if not a little disconcerting.

"In six years of growing corals, I haven't left these four walls for more than 12 hours -- not even once," he said.

"For me, it's 100% learning as I go. I take the mother colony, and I cut off a branch of the coral with a diamond saw. Then I glue it to another base made out of cement."

The delicate ecosystem needs constant care to ensure the water's salinity, temperature, and chemical make-up is perfect -- any variations and the coral could die.

The fish swimming around each tank are essentially the "worker bees" of the artificial reef. They eat the algae growing on the coral, their feces helps feed the coral, and finally, their movements in the water keep the coral strong.

And much like the traditional canary in the coalmine, if the fish die, you know something's not quite right in the water.

Clever company?

Happily for Shaham, his ambitious experiment appears to be thriving, with coral in the lab growing at ten times the normal rate.

Just a small container of the coral costs roughly $5 to $10 to produce, and sells for around $250.

One of the biggest benefits of the business is its environmental sustainability.

"We have a constant supply," says Ohad Schwartz of company CoreBone.

"We don't have to worry that in several years, harvesting from the sea could be forbidden."

It's a concern they'll never have to think about, when harvesting these remarkable fruits of the desert.

Source: http://www.cnn.com

By David McNamee

Recently, Medical News Today reported on a breakthrough in xenotransplantation - the science of transplanting functional organs from one species to another. Scientists from the Cardiothoracic Surgery Research Program of the National Heart, Lung and Blood Institute (NHLBI) demonstrated success in keeping genetically engineered piglet hearts alive in the abdomens of baboons for more than a year.

While that is a sentence that might sound absurd, or even nightmarish to some, xenotransplantation is a credible science involving the work of leading scientists and respected organizations like the NHLBI and the Mayo Clinic, as well as large private pharmaceutical firms such as United Therapeutics and Novartis.

What is more, xenotransplantation is not a new science, with experiments in cross-species blood transfusion dating as far back as the 17th century.

Why transplant the organs of animals into living humans?

The reason why xenotransplantation is a burning issue is very simple: because of a crippling shortage of available organs for patients who require transplants, many people are left to die.

US Government information on transplantation reports that an average of 79 people receive organ transplants every day, but that 18 people die each day because of a shortage of organs.

The number of people requiring an organ donation in the US has witnessed a more than five-fold increase in the past 2 decades - from 23,198 in 1991 to 121,272 in 2013. Over the same period, the number of people willing to donate has only doubled - 6,953 donors in 1991, compared with 14,257 donors in 2013.

Although some researchers are attempting to solve this shortage by developing mechanical components that could assist failing organs, these devices are considered to increase the risk of infection, blood clots and bleeding in the patient.

Stem cell research is also actively pursuing the goal of growing replacement organs, but despite regular news of breakthroughs, the reality of a functional lab-grown human organ fit for transplant is a long way off.

As the NHLBI's Dr. Muhammad M. Mohiuddin, who led the team responsible for the baboon trial, explained:

"Until we learn to grow organs via tissue engineering, which is unlikely in the near future, xenotransplantation seems to be a valid approach to supplement human organ availability. Despite many setbacks over the years, recent genetic and immunologic advancements have helped revitalized progress in the xenotransplantation field.

Xenotransplantation could help to compensate for the shortage of human organs available for transplant."

Xenotransplantation's eccentric history

The earliest known example of using animal body parts to replace diseased or faulty components of human bodies dates back to the 17th century, when Jean Baptiste Denis initiated the clinical practice of animal-to-human blood transfusion.

Perhaps predictably, the results were not successful and xenotransfusion was banned in Denis' native France.

Fast forward to the 19th century and a fairly unusual trend for skin xenotransplantation had emerged. Animals as varied as sheep, rabbits, dogs, cats, rats, chickens and pigeons were called upon to donate their skin, but the grafting process was not for the squeamish.

Medical records show that, in order for the xenosurgeons of the time to be satisfied that the donor skin had vascularized (developed capillaries), the living donor animal would usually have to be strapped to the patient for several days. However, the most popular skin donor - the frog - was typically skinned alive and then immediately grafted onto the patient.

Despite several reputed successes, modern physicians are skeptical that these skin grafts could have been in any way beneficial to the patient.

The first corneal xenotransplantation - where the cornea from a pig was implanted in a human patient - took place as early as 1838. However, scientists would not look seriously again at the potential for xenotransplantation until the 20th century and the first successes in human-to-human organ transplantation.

In 1907, the Nobel prize-winning surgeon Alexis Carrel - whose work on blood vessels made organ transplantation viable for the first time - wrote:

"The ideal method would be to transplant in man organs of animals easy to secure and operate on, such as hogs, for instance. But it would in all probability be necessary to immunize organs of the hog against the human serum. The future of transplantation of organs for therapeutic purposes depends on the feasibility of hetero [xeno] transplantation."

These words have been described as "prophetic" because Carrel is describing the exact line of research adopted by xenotransplantation scientists a century later.

A few years later, another leading scientist, Serge Voronoff, would also predict modern science's interest in using the pancreatic islets of pigs to treat severe type 1 diabetes in human patients. However, other xeno experiments by Voronoff have not endured critical reappraisal quite so well.

Voronoff's main scientific interest was in restoring the "zest for life" of elderly men. His attempt to reverse this element of the aging process was to transplant slices of chimpanzee or baboon testicle into the testicles of his elderly patients.

Incredibly, this surgery proved quite popular, with several hundred operations taking place during the 1920s in both the US and Europe.

By the 1960s, despite limited availability, the transplantation of kidneys from deceased to living humans had been established by French and American surgeons.

Dialysis was not yet in practice and given that, in the absence of an available donor kidney, his renal failure patients were facing certain death, the Louisiana surgeon Keith Reemtsma took the unprecedented step of transplanting animal kidneys. He chose chimpanzees as the donor animals, due to their close evolutionary relationship with humans.

Although 12 of his 13 chimpanzee-to-human transplants resulted in either organ rejection or infectious complications within 2 months, one patient of Reemtsma continued to live and work in good health for 9 months, before dying suddenly from acute electrolyte disturbance. Autopsy showed that the chimpanzee kidneys had not been rejected and were working normally.

Experiments in the xenotransplantation of essential organs continued in living patients until the 1980s - without lasting success. However, the procedures attracted widespread publicity, with some attributing a subsequent rise in organ donation to the failed attempt to transplant a baboon heart into a baby girl in 1983.

Where does research currently stand?

Despite the more obvious similarities between humans and other primates, pigs are now considered to be the most viable donor animal for xenotransplantation.

Despite diverging from humans on the evolutionary scale about 80 million years ago, whole genome sequencing of the pig has shown that humans and pigs share similar DNA, while the pig's organs - in size and function - are anatomically comparable to humans.

However, perhaps the main advantage of the pig as donor is in its availability - potentially providing an "unlimited supply" of donor organs. If transplantation is viable, pig donors would provide an immediate solution for the organ shortage problem.

Xenotransplantation optimists also believe that the process can improve on the existing success rate of transplantation of human organs. By keeping the pigs healthy, regularly monitored for infection, and alive right until the point when the required organs are excised under anesthesia, the adverse effects associated with transplantation from deceased donors - such as non-function of organs or transmission of pathogens - would be much less likely, this group argues.

However, there are still significant scientific barriers to the successful implementation of xenotransplantation.

The company United Therapeutics - who moved into xenotransplantation research after the daughter of CEO Martine Rothblatt was diagnosed with pulmonary hypertension, a condition with a 90% shortage rate of available lung donors - claim to be making progress with eliminating these barriers.

MedIcal News Today spoke to Rothblatt, who once claimed that the company will have successfully transplanted a pig lung into a human patient "before the end of the decade."

"For a first clinical trial, which was my goal, I think we are on track," she told us. "I said our goal by end of decade is to transplant a xeno lung into a patient with end-stage lung disease and bring them safely back to health."

As well as pioneering lung xenotransplants, the company has ambitions of making pig kidneys, livers, hearts and corneas available for human transplant.

"All are years away, but lung may well be most difficult," admits Rothblatt. "We call it the canary in the coal mine."

In order to make pig lungs compatible with humans, Rothblatt has estimated that 12 modifications need to be made to the pig genome that will prevent rejection. She claims United Therapeutics have now succeeded in making six of these genome modifications.

Also, it was United Therapeutics' genetically modified piglets that provided the world record-beating pig hearts for the NHLBI study in baboons.

Opposition to xenotransplantation

However, science is not the only obstacle to xenotransplantation. Despite clearing all steps of the research with ethics committees at every step, Rothblatt - who has a doctorate in medical ethics - admits there will be unforeseeable regulatory dilemmas and ethics conversations before xenotransplantation can be accepted into clinical practice.

In 2004, the UK's Policy Studies Institute conducted the first major survey of public attitudes towards potential solutions for the organ shortage crisis. The public perception of xenotransplantation was shown to be overwhelmingly negative.

Indeed, response to animal-to-human transplantation was so hostile that some respondents demanded that it be removed as an option on the survey. Although many respondents considered xenotransplantation unethical, the major concern was that animal viruses could infect humans and spread into the population.

Following the survey, an intriguing debate over the ethics of xenotransplantation took place in the pages of Philosophy Now. Making the case against xenotransplantation, Laura Purdy - professor emerita of philosophy at Wells College in Aurora, NY - commented that "the xeno debate proceeds as if saving lives is our top moral priority." She argues that, from this perspective, it suggests that the lives lost down the line as a result of perfecting xenotransplantation do not count.

"What about the 11 million babies and children who die every year from diarrhea, malaria, measles, pneumonia, AIDS and malnutrition?" she questioned. "What about the half-million women who die every year during pregnancy and childbirth when simple measures could save most of them?"

We asked Prof. Purdy why the fact that people die from matters unrelated to transplantation issues would morally preclude science from attempting to also solve the issue of organ donor shortages.

"I agree that, other things being equal, saying that people are dying from other causes doesn't show why we should not also tackle this cause," she replied.

"But once one has taken on board the larger risks to society, both from the research as well as the deployment of the technology, as well as the probability that this is merely a bridge technology that, hopefully will be made obsolete by future developments (such as partial or whole artificial hearts) or advances in public health (making headway against diabetes) and the probability that both research and implementation will be very expensive, that seriously erodes the case for proceeding.

Resources for health are far from infinite. There is a great deal that we could be doing now to advance human health that does not have these downsides - why not focus more there?"

Whether public attitudes toward xenotransplantation have mellowed in the decade since the Policy Studies Institute's survey is not currently known.

However, as the technology advances and the likelihood of implementation draws closer, so too must the public conversation over the perceived rights and wrongs of animal organ transplantation advance in order to hold the science accountable.

Do you have a view on this issue? If so, use our comments box to join the debate.

Source: http://www.medicalnewstoday.com