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Is Morphine a Guy Drug?

 

Science Now - Men get more relief than women do from painkillers like morphine, according to some studies. New research with rats hints at a possible explanation: Male rats have more receptors for the drug in a brain region involved in pain processing. Although it's not yet clear whether the same is true in humans, researchers say the study underscores the need for more research on the sex-specific effects of pain drugs.
The new study used rats in part because they exhibit a clear sex difference in morphine sensitivity, explains lead researcher Anne Murphy, a neuroscientist at Georgia State University in Atlanta. In a standard lab test, for example, both male and female rats will withdraw a paw from a hot probe in 8 or 9 seconds. After a shot of morphine, the females might tolerate the probe for another second or two, but males let the paw linger up to 20 seconds, Murphy says.

In tomorrow's Journal of Neuroscience, Murphy and colleagues report that male rats have a higher density of μ-opioid receptors in a portion of the periaqueductal gray, a brain region implicated in previous experiments as a likely site of action for opioid drugs like morphine. Injecting morphine directly into this area had a powerful analgesic effect for male, but not female, rats. When the researchers killed neurons with μ-opioid receptors by injecting a toxin bound to a morphine lookalike compound, the drug lost its analgesic effect for males, but not females. Murphy says the findings, taken together, suggest that the difference in μ-opioid receptors in the periaqueductal gray explains the sex difference in morphine sensitivity in rats.

A better understanding of underlying neurobiology could one day lead to more effective pain drugs for women, Murphy says, adding that human studies have suggested that morphine produces less analgesia--and more side effects--in women.

"This is ... a breakthrough in finding a viable mechanism of action for sex differences in opiate analgesia in animals," says Richard Bodnar, a neuroscientist at City University of New York, Queens College. Other researchers have suggested that there may be sex differences in opioid receptor number or function in pain-related areas of the brain, but "this work is the first to definitively demonstrate such differences," says neuroscientist Rebecca Craft of Washington State University, Pullman.

Could it also explain differences in opioid sensitivity in people? "There are probably some parallels," says Craft, "but it's a bit early to tell how strong the relationship is between human and animal work in this area."

 


Processed Foods Linked to Lung Cancer

 

Why do some people get lung cancer – even if they never smoke? New research suggests eating a lot of processed foods containing inorganic phosphates could be the explanation. What's more, the study also suggests that dietary changes to avoid these chemical additives may play an important role in lung cancer treatment.

In research just published in the January issue of American Journal of Respiratory and Critical Care Medicine, published by the American Thoracic Society, scientists from Seoul National University conclude that a diet high in inorganic phosphates, which are found in a host of processed foods including meats, cheeses, beverages, and bakery products, might spur the growth of lung cancer. The researchers also suggest the food additive may contribute to the development of malignancies in people predisposed to lung cancer.

Myung-Haing Cho, D.V.M., Ph.D., and his colleagues studied mice with lung cancer tumors for four weeks. The rodents were randomly assigned to eat a diet of either 0.5 or 1.0 percent phosphate, a range roughly equivalent to what's found in most modern human diets that contain processed foods. At the end of the study period, the animals' lung tissues were analyzed to see what effects the inorganic phosphates had on tumors.

"Our results clearly demonstrated that the diet higher in inorganic phosphates caused an increase in the size of the tumors and stimulated growth of the tumors," Dr. Cho said in a statement to the press. "Our study indicates that increased intake of inorganic phosphates strongly stimulates lung cancer development in mice, and suggests that dietary regulation of inorganic phosphates may be critical for lung cancer treatment as well as prevention." [ More ]

 


Grape-seed Extract Kills Laboratory Leukemia Cells

 

An extract from grape seeds forces laboratory leukemia cells to commit cell suicide, according to researchers from the University of Kentucky. They found that within 24 hours, 76 percent of leukemia cells had died after being exposed to the extract.

The investigators, who report their findings in the January 1, 2009, issue of Clinical Cancer Research, a journal of the American Association for Cancer Research, also teased apart the cell signaling pathway associated with use of grape seed extract that led to cell death, or apoptosis. They found that the extract activates JNK, a protein that regulates the apoptotic pathway.

While grape seed extract has shown activity in a number of laboratory cancer cell lines, including skin, breast, colon, lung, stomach and prostate cancers, no one had tested the extract in hematological cancers nor had the precise mechanism for activity been revealed.

"These results could have implications for the incorporation of agents such as grape seed extract into prevention or treatment of hematological malignancies and possibly other cancers," said the study's lead author, Xianglin Shi, Ph.D., professor in the Graduate Center for Toxicology at the University of Kentucky.

"What everyone seeks is an agent that has an effect on cancer cells but leaves normal cells alone, and this shows that grape seed extract fits into this category," he said.

Shi adds, however, that the research is not far enough along to suggest that people should eat grapes, grape seeds, or grape skin in excess to stave off cancer. "This is very promising research, but it is too early to say this is chemo-protective."

Hematological cancers – leukemia, lymphoma and myeloma – accounted for an estimated 118,310 new cancer cases and almost 54,000 deaths in 2006, ranking these cancers as the fourth leading cause of cancer incidence and death in the U.S.

Given that epidemiological evidence shows that eating vegetables and fruits helps prevent cancer development, Shi and his colleagues have been studying chemicals known as proanthocyanidins in fruits that contribute to this effect. Shi has found that apple peel extract contains these flavonoids, which have antioxidant activity, and which cause apoptosis in several cancer cell lines but not in normal cells. Based on those studies, and findings from other researchers that grape seed extract reduces breast tumors in rats and skin tumors in mice, they looked at the effect of the compound in leukemia cells.

Using a commercially available grape seed extract, Shi exposed leukemia cells to the extract in different doses and found the marked effect in causing apoptosis in these cells at one of the higher doses.

They also discovered that the extract does not affect normal cells, although they don't know why.

The researchers then used pharmacologic and genetic approaches to determine how the extract induced apoptosis. They found that the extract strongly activated the JNK pathway, which then led to up-regulation of Cip/p21, which controls the cell cycle.

They checked this finding by using an agent that inhibited JNK, and found that the extract was ineffective. Using a genetic approach – silencing the JNK gene – also disarmed grape seed extract's lethal attack in leukemia cells. "This is a natural compound that appears to have relatively important properties," Shi said.

 


Nanoparticles delivering drugs can kill skin, breast cancer cells

 

Researchers in Pennsylvania are reporting for the first time that nanoparticles 1/5,000 the diameter of a human hair encapsulating an experimental anticancer agent, kill human melanoma and drug-resistant breast cancer cells growing in laboratory cultures.

 

The discovery could lead to the development of a new generation of anti-cancer drugs that are safer and more effective than conventional chemotherapy agents, the scientists suggest.

The research is scheduled for the Dec. 10 issue of ACS' Nano Letters, a monthly journal.

In the new study, Mark Kester, James Adair and colleagues at Penn State's Hershey Medical Center and University Park campus point out that certain nanoparticles have shown promise as drug delivery vehicles. However, many of these particles will not dissolve in body fluids and are toxic to cells, making them unsuitable for drug delivery in humans. Although promising as an anti-cancer agent, ceramide also is insoluble in the blood stream making delivery to cancer cells difficult.

The scientists report a potential solution with development of calcium phosphate nanocomposite particles (CPNPs). The particles are soluble and with ceramide encapsulated with the calcium phosphate, effectively make ceramide soluble. With ceramide encapsulated inside, the CPNPs killed 95 percent of human melanoma cells and was "highly effective" against human breast cancer cells that are normally resistant to anticancer drugs, the researchers say.

Penn State Research Foundation has licensed the calcium phosphate nanocomposite particle technology known as "NanoJackets" to Keystone Nano, Inc. MK and JA are CMO and CSO, respectively.

 


Sleep gives brain disease warning

 

Physically "acting out" dreams when asleep could be an early warning sign of dementia or Parkinson's disease.

Canadian researchers studied 93 people with "REM sleep behaviour disorder", which can involve punching or kicking out while dreaming.

The Neurology study found more than a quarter were diagnosed with a degenerative brain condition over the next five years.

UK experts said the research could help doctors predict the condition.

Normally, during "Rapid Eye Movement," or "REM" sleep, our muscles relax and do not move, but people with certain sleep disorders are able to lash out, or cry out.

It is a known symptom of some kinds of brain disease, including Parkinson's disease, and a rare form of dementia called Lewy body dementia. This important finding could boost our understanding of how Lewy body dementia develops and help us detect it early

The exact reason for the link is unclear, although some have suggested that subtle damage to a part of the brain which regulates sleep may be responsible.

However, in some cases, the problem happens long before the onset of the main symptoms of these diseases, and doctors at Montreal General Hospital wanted to see whether apparently otherwise healthy people with the problem were at higher risk.

Their study volunteers were all elderly - on average 65 years old - which already put them at higher risk of developing dementia or Parkinson's compared with a younger person.

However, each was followed on average for five years, and in that period, 26 of the 93 developed a degenerative brain disease.

In total, 14 were diagnosed with Parkinson's disease, seven with Lewy body dementia, four with Alzheimer's Disease, and another diagnosed with a disorder called multiple system atrophy, which involves both Parkinson's and dementia symptoms.

Their predictions suggested that patients of this age with the same sleep disorder would have a greater than 50/50 chance of falling prey to a similar condition over the following 12 years.

The researchers said that knowing more about the risks faced by people with the sleep disorder could not only help doctors to advise their patients, but also to work in the years to come to come up with ways to protect them.

Dr Susanne Sorensen, head of research at the Alzheimer's Society, said that the findings were particularly interesting in relation to Lewy body dementia, which accounts for only 4% of dementia cases.

The researchers had said that even the four Alzheimer's cases might turn out to be Lewy body dementia as the disease progressed.

Dr Sorensen said: "People with Lewy body dementia often have vivid nightmares, restless sleep and hallucinations - this study suggests that people with the disease may experience sleep disorders years before their other symptoms develop.

"This important finding could boost our understanding of how Lewy body dementia develops and help us detect it early. With further research we may be able to stop this devastating disease in its tracks."

 


Origin Of Life On Earth: Simple Fusion To Jump-start Evolution

 

ScienceDaily  — With the aid of a straightforward experiment, researchers have provided some clues to one of biology's most complex questions: how ancient organic molecules came together to form the basis of life.

RNA, the single-stranded precursor to DNA, normally expands one nucleic base at a time, growing sequentially like a linked chain. The problem is that in the primordial world RNA molecules didn't have enzymes to catalyze this reaction, and while RNA growth can proceed naturally, the rate would be so slow the RNA could never get more than a few pieces long (for as nucleic bases attach to one end, they can also drop off the other).

Ernesto Di Mauro and colleagues examined if there was some mechanism to overcome this thermodynamic barrier, by incubating short RNA fragments in water of different temperatures and pH.

They found that under favorable conditions (acidic environment and temperature lower than 70 degrees Celsius), pieces ranging from 10-24 in length could naturally fuse into larger fragments, generally within 14 hours.

The RNA fragments came together as double-stranded structures then joined at the ends. The fragments did not have to be the same size, but the efficiency of the reactions was dependent on fragment size (larger is better, though efficiency drops again after reaching around 100) and the similarity of the fragment sequences.

The researchers note that this spontaneous fusing, or ligation, would a simple way for RNA to overcome initial barriers to growth and reach a biologically important size; at around 100 bases long, RNA molecules can begin to fold into functional, 3D shapes.

 


Scientist: stem cells could end animal testing

 

As well as their potential for creating effective therapies for debilitating diseases, embryonic stem cells could open the door to more effective pharmaceutical drug testing, according to a leading British stem cell researcher.

 

Speaking at a recent meeting of the British Pharmacological Society in Brighton, UK, Christine Mummery described how using embryonic stem cells to create human heart cells could be a viable and scientifically exciting alternative to animal testing.

Mummery, a Professor of Developmental Biology at Leiden University Medical Center in The Netherlands told CNN: "It could save a lot of time and effort of taking the wrong drugs through, or it may allow drugs through which are lost at an early stage, because they affect the animal cells but don't have an effect on human cells.

"It may also allow more and better drugs to come through the first tests or flag up safety issues at an earlier stage."
 

Before new drugs can go forward for clinical trials, it's necessary for the chemical compounds which make up a drug to undergo thousands of tests for toxicity before beginning trials on animals -- initially on rodents and then often on dogs.

It's here, at this ethically sensitive stage, that Professor Mummery believes stem cell research could transform drug development.

"Many drugs are designed to affect the heart deliberately, controlling beats and rates of contraction," said Mummery, who specializes in converting embryonic stem cells into cardiac and vascular cells.

But, as she points out, plenty of drugs designed to treat other complaints can also have negative side effects on the heart -- the painkiller Vioxx being a notable example.

Stem cell based drug testing is already being promoted in the UK with the public/private initiative "Stem Cells for Safer Medicine" which was set up in 2007.

It's something Mummery hopes will be replicated in other countries and particularly in the U.S. under President-elect Obama who is a proponent of stem cell research.
 

A 2007 sabbatical at the Harvard Stem Cell Institute in Cambridge, Massachusetts gave Mummery first-hand experience of the ethical debates that have engulfed stem cell research debates in the U.S..

"I was shocked at the light years we are away from the way people think about embryonic stem cells in the States," she said. "It's very mixed up with the abortion issue. It's put into the same category."

Public funding, or the lack of it, under President George W. Bush has also stymied research.

"What's happened in the U.S. is that people have become very frustrated and a lot of private initiatives -- like the Harvard Stem Cell Institute -- were started up to circumvent the lack of National Institute of Health (NIH) funding. NIH researchers are either left behind or have a huge administrative burden," Mummery said.

Drug company interest in stem cell drug testing was demonstrated in July 2008, when GlaxoSmithKline entered into a $25 million-plus agreement with the Harvard Stem Cell Institute.

Commenting on the deal, Professor Patrick Vallance, Head of Drug Discovery at GSK said: "GSK believes stem cell science has great potential to aid the discovery of new medicines by improving the screening, identification and development of new compounds."

Clearly, the BUAV would like to do away with all animal testing altogether. Their obvious ethical objections, are backed up by questions about its efficacy.

"One of issues with drug development," Thew said, "is that animal testing is not very successful at getting drugs through the process because a lot of the tests aren't very predictive. They are also very expensive and time-consuming."

 

 


Genes May Influence Popularity, Study Of Students Finds

 

ScienceDaily — A groundbreaking study of popularity by a Michigan State University scientist has found that genes elicit not only specific behaviors but also the social consequences of those behaviors.

 

According to the investigation by behavioral geneticist S. Alexandra Burt, male college students who had a gene associated with rule-breaking behavior were rated most popular by a group of previously unacquainted peers.

It’s not unusual for adolescent rule-breakers to be well-liked – previous research has made that link – but Burt is the first to provide meaningful evidence for the role of a specific gene in this process. The study appears in the latest issue of the Journal of Personality and Social Psychology, which is published by the American Psychological Association.

“The idea is that your genes predispose you to certain behaviors and those behaviors elicit different kinds of social reactions from others,” said Burt, assistant professor of psychology. “And so what’s happening is, your genes are to some extent driving your social experiences.”

The concept – which researchers call “evocative gene-environment correlation” – had been discussed in scientific literature but only in theory. This study is the first to really flesh out the process, establishing clear connections between a specific gene, particular behaviors and actual social situations, she said.

Burt collected DNA from more than 200 male college students in two separate samples. After interacting in a lab setting for about an hour, the students filled out a questionnaire about whom they most liked in their group. In both samples, the most popular students turned out to be the ones with a particular form of a serotonin gene that was also associated with rule-breaking behavior.

“So the gene predisposed them to rule-breaking behavior and their rule-breaking behavior made them more popular,” Burt said.

Burt is working on similar studies with female college students, as well as mixed-gender social groups. She also plans to explore associations with other social behaviors and other genes in larger samples.

 


Pain Hurts More If Person Hurting You Means It

 

Researchers at Harvard University have discovered that our experience of pain depends on whether we think someone caused the pain intentionally. In their study, participants who believed they were getting an electrical shock from another person on purpose, rather than accidentally, rated the very same shock as more painful. Participants seemed to get used to shocks that were delivered unintentionally, but those given on purpose had a fresh sting every time.

The research, published in the current issue of Psychological Science, was led by Kurt Gray, a graduate student in psychology, along with Daniel Wegner, professor of psychology.

It has long been known that our own mental states can alter the experience of pain, but these findings suggest that our perceptions of the mental states of others can also influence how we feel pain.

"This study shows that even if two harmful events are physically identical, the one delivered with the intention to hurt actually hurts more," says Gray. "Compare a slap from a friend as she tries to save us from a mosquito versus the same slap from a jilted lover. The first we shrug off instantly, while the second stings our cheek for the rest of the night."

The study's authors suggest that intended and unintended harm cause different amounts of pain because they differ in meaning.

"From decoding language to understanding gestures, the mind distills meaning from our social environment," says Gray. "An intended harm has a very different meaning than an accidental harm."

The study included 48 participants who were paired up with a partner who could administer to them either an audible tone or an electric shock. In the intentional condition, participants were shocked when their partner chose the shock option. In the unintentional condition, participants were shocked when their partner chose the tone option. Thus, in this condition, they only received a shock when their partner did not intend them to receive one. The computer display ensured that participants both knew their partner's choice and that a shock would be coming, to ensure the shock was not more surprising in the unintentional condition.

Despite identical shock voltage between conditions, those in the intentional condition rated the shocks as significantly more painful. Furthermore, those in the unintentional condition habituated to the pain, rating them as decreasingly painful, while those in the intentional condition continued to feel the full sting of pain.

Gray suggests that it may be evolutionarily adaptive for this difference in meaning to be represented as different amounts of pain.

"The more something hurts, the more likely we are to take notice and stop whatever is hurting us," he says. "If it's an accidental harm, chances are it's a one-time thing, and there's no need to do anything about it. If it's an intentional harm, however, it may be the first of many, so it's good to take notice and do something about it. It makes sense that our bodies and brains might amplify our experience of pain when we know that the pain could signal threats to our survival."

These findings speak to how people experience pain and negative life events. If negative events are seen as intended, they may hurt more. This helps to explain why torture is so excruciating – not only are torture techniques themselves exceptionally painful, but it's the thought that counts—and makes torture hurt more than mere pain.

On the other hand, if negative events are seen as unintended, they may hurt less. This may explain, in part, why people in abusive relationships sometimes continue to stay in them. By rationalizing that an abusive partner did not intend harm, some victims may reduce their experience of pain, which could make them less likely to leave the relationship and escape the abuse.

The research was supported by the National Institute of Mental Health, the Canadian Social Sciences and Humanities Research Council and the Institute for Humane Studies.

 


Scientists use PlayStations to create supercomputer

 

CBC.ca — Computer hobbyists and researchers take note: two U.S. scientists have created a step-by-step guide on how to build a supercomputer using multiple PlayStation 3 video-game consoles.

The instructional guide, posted this week online at ps3cluster.org, allows users with some programming knowledge to install a version of the open-source operating system Linux on the video consoles and connect a number of consoles into a computing cluster or grid.

The two researchers say the guide could provide scientists with another, cheaper alternative to renting time on supercomputers to run their simulations.

University of Massachusetts Dartmouth physics professor Gaurav Khanna first built the cluster a year ago to run his simulations estimating the gravitational waves produced when two black holes merged.

Frustrated with the cost of renting time on supercomputers, which he said can cost as much as $5,000 to run a 5,000-hour simulation, Khanna decided to set up his own computer cluster using PS3s, which had both a powerful processor developed by Sony, IBM and Toshiba, but also an open platform that allows different system software to run on it. PlayStation 3 systems retail for about $400 Cdn.

On the how-to-guide Khanna says the eight-console cluster is roughly comparable in speed to a 200 node IBM Blue Gene supercomputer. Khanna says his research now runs using a cluster of 16 PS3s.

The fastest supercomputer in the world, IBM's Roadrunner supercomputer at Los Alamos National Laboratory, has 3,250 nodes and is capable of 1.105 petaflops, or 1.105 quadrillion floating point operations per second, about 100,000 times faster than a home computer.

Massachusetts Dartmouth computer scientist Chris Poulin, who co-wrote the instructional manual with Khanna, wouldn't reveal the number of flops the system can achieve, but said anecdotally the cluster has allowed him to run simulations in hours that used to take days on a powerful server computer.

Khanna's not the first researcher to use PS3s to simulate the effects of a supercomputer. The University of Stanford's Folding at Home project allows people to help with research into how proteins self-assemble — or fold — by downloading software onto their home PS3s, creating a virtual supercomputer. Their research is currently targeting proteins relevant to diseases such as Alzheimer's and Huntington's disease.

But the guide posted by Khanna and Poulin is the first that might allow someone to set up a supercomputer in their own home.

Poulin said there are two major practical issues, however, that might limit the practicality of a PS3 cluster supercomputer.

The first issue is power. He said the video-game consoles use about 200 to 300 watts per unit, so finding a room that could hook up eight of the consoles might be an issue for hobbyists, he says.

"I think if you put four or more than four of the systems on one plug you'd probably blow a fuse," Poulin said.

The second issue is memory. The console has only 256 MB of RAM, far less than most personal computers available now. Poulin said that while the low memory wouldn't be a problem for straightforward computations, running multiple simulations or programs could tax the system. As a result, simulations running on the cluster would have to be tailored to consider the cluster's memory limitations.

Poulin said he hopes the project will help open doors to more partnerships between industry and universities that will lead to better access to supercomputing power.

 


The Future of Man — How Will Evolution Change Humans?

 

Scientific American - People commonly assume that our species has evolved very little since prehistoric times. Yet new studies using genetic information from populations around the globe suggest that the pace of human evolution increased with the advent of agriculture and cities.


If we are still evolving, what might our species look like in a millennium should we survive whatever environ­mental and social surprises are in store for us? Specu­la­tion ranges from the hopeful to the dystopian.

 

When you ask for opinions about what future humans might look like, you typically get one of two answers. Some people trot out the old science-fiction vision of a big-brained human with a high forehead and higher intellect. Others say humans are no longer evolving physically—that technology has put an end to the brutal logic of natural selection and that evolution is now purely cultural.

The big-brain vision has no real scientific basis. The fossil record of skull sizes over the past several thousand generations shows that our days of rapid increase in brain size are long over. Accordingly, most scientists a few years ago would have taken the view that human physical evolution has ceased. But DNA techniques, which probe genomes both present and past, have unleashed a revolution in studying evolution; they tell a different story. Not only has Homo sapiens been doing some major genetic reshuffling since our species formed, but the rate of human evolution may, if anything, have increased. In common with other organisms, we underwent the most dramatic changes to our body shape when our species first appeared, but we continue to show genetically induced changes to our physiology and perhaps to our behavior as well. Until fairly recently in our history, human races in various parts of the world were becoming more rather than less distinct. Even today the conditions of modern life could be driving changes to genes for certain behavioral traits.

If giant brains are not in store for us, then what is? Will we become larger or smaller, smarter or dumber? How will the emergence of new diseases and the rise in global temperature shape us? Will a new human species arise one day? Or does the future evolution of humanity lie not within our genes but within our technology, as we augment our brains and bodies with silicon and steel? Are we but the builders of the next dominant intelligence on the earth—the machines?

The Far and Recent Past


Tracking human evolution used to be the province solely of paleontologists, those of us who study fossil bones from the ancient past. The human family, called the Hominidae, goes back at least seven million years to the appearance of a small proto-human called Sahelanthropus tchadensis. [ More ]

 


Scientists ask: Is technology rewiring our brains?

 

(AP) - What does a teenage brain on Google look like? Do all those hours spent online rewire the circuitry? Could these kids even relate better to emoticons than to real people? These sound like concerns from worried parents. But they're coming from brain scientists.

While violent video games have gotten a lot of public attention, some current concerns go well beyond that. Some scientists think the wired world may be changing the way we read, learn and interact with each other.

There are no firm answers yet. But Dr. Gary Small, a psychiatrist at UCLA, argues that daily exposure to digital technologies such as the Internet and smart phones can alter how the brain works.

When the brain spends more time on technology-related tasks and less time exposed to other people, it drifts away from fundamental social skills like reading facial expressions during conversation, Small asserts.

 

So brain circuits involved in face-to-face contact can become weaker, he suggests. That may lead to social awkwardness, an inability to interpret nonverbal messages, isolation and less interest in traditional classroom learning.

Small says the effect is strongest in so-called digital natives - people in their teens and 20s who have been "digitally hard-wired since toddlerhood." He thinks it's important to help the digital natives improve their social skills and older people - digital immigrants - improve their technology skills.

 

At least one 19-year-old Internet enthusiast gives Small's idea a mixed review. John Rowe, who lives near Pasadena, Calif., spends six to 12 hours online a day. He flits from instant messaging his friends to games like Cyber Nations and Galaxies Ablaze to online forums for game players and disc jockeys.

Social skills? Rowe figures he and his buddies are doing just fine in that department, thank you. But he thinks Small may have a point about some other people he knows.

"If I didn't actively go out and try to spend time with friends, I wouldn't have the social skills that I do," said Rowe, who reckons he spends three or four nights a week out with his pals. "You can't just give up on having normal friends that you see on a day-to-day basis."

More than 2,000 years ago, Socrates warned about a different information revolution - the rise of the written word, which he considered a more superficial way of learning than the oral tradition. More recently, the arrival of television sparked concerns that it would make children more violent or passive and interfere with their education.
 [ More ]

 


A toke a day keeps memory loss at bay

 

Globe and Mail - Turns out a few dances with Mary Jane can do wonders for an aging brain.

Yes, a daily toke in later-middle and old age can help slow memory loss, or the onset of diseases such as Alzheimer's, Parkinson's and multiple sclerosis, a new study suggests.

It's a pre-emptive strike, one not effective at reversing previous memory loss. But aging boomers still shouldn't go overboard, researchers say. In tests on lab rats, all it took was the equivalent of one human puff.

"We are not trying to make anyone high," said Gary Wenk, professor of psychology and neuroscience at Ohio State University. "We are trying to tease out the positive aspects of this plant."

The benefit was found in a synthetic compound identical to tetrahydrocannabinol, or THC, the psychoactive substance in marijuana, which researchers say activated areas of aged brains in rats affected by memory loss, and stimulated the formation of new brain cells.

Prof. Wenk, who presented the research in Washington, yesterday at the annual meeting of the Society for Neuroscience, was motivated to look into the effects of marijuana on aging brains after repeatedly noticing the drug mentioned on the blogs of patients with MS who use it to curb pain. Memory impairment is connected to such chronic brain inflammation.

"There was discussion of smoking a little pot to reduce inflammation, which makes their disease less painful," Prof. Wenk said.

Pot is popular among older sufferers, because conventional anti-inflammatory medications are not effective in older brains.

"Millions of people have used this plant for thousands of years," Prof. Wenk said. "There is a lot of evidence that there are some interesting things going on in the brains of these people."

So, while testing with rats, researchers used a THC-like drug, called WIN-55212-2, to activate receptors in the brain's endocannabinoid system - usually stimulated by smoking marijuana - which involves memory, appetite, mood and pain response.

After three weeks, the rats were given a memory test where they were placed in a small swimming pool to determine how well they used visual cues to find a platform hidden under the surface of the water.

The treated rats were given enough of the drug to boost brain cells, though not enough to get high, and did better in the swimming-pool test than the control - strait-laced rats without THC - in learning and remembering how to find the hidden platform.

"Old rats are not very good at that task," said Yannick Marchalant, co-author of the study and assistant professor of psychology at Ohio State. "When we gave them the drug, it made them a little better at that task."

They also experienced reduced inflammation and growth of new brain cells.

The researchers hope their findings could lead to the development of a drug to stave off memory loss in people with a history of degenerative disease in their families.

"The model could be used for anyone at risk," Prof. Marchalant said. "Perhaps 20 years before the usual onset of the decline in memory."

Cannabis joins a long list of taboo substances now shown to reduce brain inflammation. Nicotine, alcohol and caffeine have also been shown to do so, possibly leading to reduced memory loss later in life.

"What is it about coffee, what is it about smoking and what is it about marijuana that is causing us to see these effects?" Prof. Wenk asked. "Different compounds that may be bad for one part of the brain may be good for another."

 

 

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