Chapter 4. The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
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Ian Sample Science editor They were once considered merely lazy and adorable. But new research into the antics of the slow loris has revealed a wilder side to the docile creatures. Given the chance the innocent-eyed beasts will neck the most alcoholic drinks they can lay their paws on. The ability of the slow loris to seek out the most potent brew in reach was discovered by researchers in the US who wanted to know whether the animals favoured highly-fermented nectar over the less alcoholic forms secreted by plants in their natural habitats. As sugary nectar ferments in the wild, its calorie content rises, making it a potentially more valuable source of energy. In a series of tests with Dharma, an adult female slow loris, biologists at Dartmouth College in New Hampshire found that when presented with a choice of sugary solutions laced with different amounts of alcohol, the loris speedily settled on the most intoxicating. But while the animal was quickly drawn to the nectar substitutes, which contained between 1% and 4% alcohol, the slow loris displayed what the researchers describe as “a relative aversion to tap water”, which was used as a control. Dharma was not alone in her taste for drink. The scientists ran the same series of experiments with two nocturnal aye aye lemurs, a male called Merlin and a female called Morticia. Once again, the primates homed in on the most alcoholic of sugary solutions the researchers knocked up to mimic fermented nectar. © 2016 Guardian News and Media Limited
Research supported by the National Institutes of Health has identified brain patterns in humans that appear to underlie “resilient coping,” the healthy emotional and behavioral responses to stress that help some people handle stressful situations better than others. People encounter stressful situations and stimuli everywhere, every day, and studies have shown that long-term stress can contribute to a broad array of health problems. However, some people cope with stress better than others, and scientists have long wondered why. The new study, by a team of researchers at Yale University, New Haven, Connecticut, is now online in the Proceedings of the National Academy of Sciences. “This important finding points to specific brain adaptations that predict resilient responses to stress,” said George F. Koob, Ph.D., director of the National Institute on Alcohol Abuse and Alcoholism (NIAAA), part of NIH and a supporter of the study. “The findings also indicate that we might be able to predict maladaptive stress responses that contribute to excessive drinking, anger, and other unhealthy reactions to stress.” In a study of human volunteers, scientists led by Rajita Sinha, Ph.D., and Dongju Seo, Ph.D., used a brain scanning technique called functional magnetic resonance imaging (fMRI) to measure localized changes in brain activation during stress. Study participants were given fMRI scans while exposed to highly threatening, violent and stressful images followed by neutral, non-stressful images for six minutes each. While conducting the scans, researchers also measured non-brain indicators of stress among study participants, such as heart rate, and levels of cortisol, a stress hormone, in blood. The brain scans revealed a sequence of three distinct patterns of response to stress, compared to non-stress exposure.
By Maia Szalavitz When a family member, spouse or other loved one develops an opioid addiction — whether to pain relievers like Vicodin or to heroin — few people know what to do. Faced with someone who appears to be driving heedlessly into the abyss, families often fight, freeze or flee, unable to figure out how to help. Families are sometimes overwhelmed with conflicting advice about what should come next. Much of the advice given by treatment groups and programs ignores what the data says in a similar way that anti-vaccination or climate skeptic websites ignore science. The addictions field is neither adequately regulated nor effectively overseen. There are no federal standards for counseling practices or rehab programs. In many states, becoming an addiction counselor doesn’t require a high school degree or any standardized training. “There’s nothing professional about it, and it’s not evidence-based,” said Dr. Mark Willenbring, the former director of treatment research at the National Institute on Alcohol Abuse and Alcoholism, who now runs a clinic that treats addictions. Consequently, families are often given guidance that bears no resemblance to what the research evidence shows — and patients are commonly subjected to treatment that is known to do harm. People who are treated as experts firmly proclaim that they know what they are doing, but often turn out to base their care entirely on their own personal and clinical experience, not data. “Celebrity Rehab with Dr. Drew,” which many people see as an example of the best care available, for instance, used an approach that is not known to be effective for opioid addiction. More than 13 percent of its participants died after treatment,1 mainly of overdoses that could potentially have been prevented with evidence-based care. Unethical practices such as taking kickbacks for patient referrals are also rampant.
By SARAH MASLIN NIR Almost as soon as the young man crouching on a trash-strewed street in Brooklyn pulled out a crumpled dollar bill from his pocket and emptied its contents of dried leaves into a wrapper, he had company. A half-dozen disheveled men and women walked swiftly to where the young man was rolling a cigarette of a synthetic drug known as K2 to wait for a chance to share. The drug has been the source of an alarming and sudden surge in overdoses — over three days this week, 130 people across New York City were treated in hospital emergency rooms after overdosing on K2, almost equaling the total for the entire month of June, according to the city’s health department. About one-fourth of the overdoses, 33, took place on Tuesday along the border of Bedford-Stuyvesant and Bushwick, the same Brooklyn neighborhoods where, despite a heightened presence of police officers, people were again openly smoking the drug on Thursday. In response to the overdoses, the city is sending a health alert to emergency rooms and other health care providers warning about the drug. The outbreak comes after officials this spring lauded what they described as a successful campaign to severely curb the prevalence of K2. On Thursday, Gov. Andrew M. Cuomo announced that the State Police would step up enforcement against the drug and aggressively go after merchants who illegally sell it. The same day, just steps from where people were using the drug, clusters of police officers patrolled beneath the elevated subway tracks along a stretch where, the day before, five bodegas had been raided. K2 is typically sold by convenience stores, though the raids did not turn up any. © 2016 The New York Times Company
Keyword: Drug Abuse
Link ID: 22448 - Posted: 07.16.2016
Suzi Gage Ketamine hydrochloride is a synthetic dissociative anaesthetic. It was first synthesized in the 1960s for medical use, and was first used medicinally during the Vietnam war. Recreationally, it is usually consumed by snorting a white crystalline powder, and at lower doses than when it’s used as an anaesthetic. However it can also be injected, or smoked. It is used in a club setting, but also as a psychedelic. Short term effects When ketamine is snorted, it gets in to the blood stream quickly, and intoxication effects occur soon after it’s taken. Although it’s an anaesthetic, at low doses it raises heart rate. It’s also associated with cognitive impairment during intoxication, including to speech and executive function. It can also induce mild psychedelic effects such as perceptual changes and psychotic-like experiences, which are appealing to some users, but can also be distressing. At slightly higher doses, users can experience a dissociative state, where their mind feels separated from their body. This can also manifest as a feeling of depersonalization. At higher doses, the anaesthetic quality of ketamine becomes more pronounced. People may find it difficult to move and may feel numb, and can experience more vivid hallucinations. This is sometimes called the ‘k-hole’ by users. Amnesia can occur at this level of use. This is a particular danger of using ketamine recreationally: users are vulnerable to assault from others in this state, or can put themselves in danger by not being aware of their surroundings (for example being unaware they are outside and it is cold can lead to hypothermia, or being unaware of surroundings could lead to walking in to traffic). © 2016 Guardian News and Media Limited
Keyword: Drug Abuse
Link ID: 22436 - Posted: 07.14.2016
By Anahad O'Connor Like most of my work, this article would not have been possible without coffee. I’m never fully awake until I have had my morning cup of espresso. It makes me productive, energized and what I can only describe as mildly euphoric. But as one of the millions of caffeine-loving Americans who can measure out my life with coffee spoons, (to paraphrase T.S. Eliot), I have often wondered: How does my coffee habit impact my health? The health community can’t quite agree on whether coffee is more potion or poison. The American Heart Association says the research on whether coffee causes heart disease is conflicting. The World Health Organization, which for years classified coffee as “possibly” carcinogenic, recently reversed itself, saying the evidence for a coffee-cancer link is “inadequate.” National dietary guidelines say that moderate coffee consumption may actually be good for you – even reducing chronic disease. Why is there so much conflicting evidence about coffee? The answer may be in our genes. About a decade ago, Ahmed El-Sohemy, a professor in the department of nutritional sciences at the University of Toronto, noticed the conflicting research on coffee and the widespread variation in how people respond to it. Some people avoid it because just one cup makes them jittery and anxious. Others can drink four cups of coffee and barely keep their eyes open. Some people thrive on it. Dr. El-Sohemy suspected that the relationship between coffee and heart disease might also vary from one individual to the next. And he zeroed in on one gene in particular, CYP1A2, which controls an enzyme – also called CYP1A2 – that determines how quickly our bodies break down caffeine. One variant of the gene causes the liver to metabolize caffeine very quickly. People who inherit two copies of the “fast” variant – one from each parent – are generally referred to as fast metabolizers. Their bodies metabolize caffeine about four times more quickly than people who inherit one or more copies of the slow variant of the gene. These people are called slow metabolizers. © 2016 The New York Times Company
Tough love, interventions and 12-step programs are some of the most common methods of treating drug addiction, but journalist Maia Szalavitz says they're often counterproductive. "We have this idea that if we are just cruel enough and mean enough and tough enough to people with addiction, that they will suddenly wake up and stop, and that is not the case," she tells Fresh Air's Terry Gross. Szalavitz is the author of Unbroken Brain, a book that challenges traditional notions of addiction and treatment. Her work is based on research and experience; she was addicted to cocaine and heroin from the age of 17 until she was 23. Szalavitz is a proponent of "harm reduction" programs that take a nonpunitive approach to helping addicts and "treat people with addiction like human beings." In her own case, she says that getting "some kind of hope that I could change" enabled her to get the help she needed. On her criticism of 12-step programs I think that 12-step programs are fabulous self help. I think they can be absolutely wonderful as support groups. My issue with 12-step programs is that 80 percent of addiction treatment in this country consists primarily of indoctrinating people into 12-step programs, and no other medical care in the United States is like that. The data shows that cognitive behavioral therapy and motivational enhancement therapy are equally effective, and they have none of the issues around surrendering to a higher power, or prayer or confession. © 2016 npr
Keyword: Drug Abuse
Link ID: 22408 - Posted: 07.08.2016
Shefali Luthra Prescription drug prices continue to climb, putting the pinch on consumers. Some older Americans appear to be seeking an alternative to mainstream medicines that has become easier to get legally in many parts of the country. Just ask Cheech and Chong. Research published Wednesday found that states that legalized medical marijuana — which is sometimes recommended for symptoms like chronic pain, anxiety or depression — saw declines in the number of Medicare prescriptions for drugs used to treat those conditions and a dip in spending by Medicare Part D, which covers the cost on prescription medications. Because the prescriptions for drugs like opioid painkillers and antidepressants — and associated Medicare spending on those drugs — fell in states where marijuana could feasibly be used as a replacement, the researchers said it appears likely legalization led to a drop in prescriptions. That point, they said, is strengthened because prescriptions didn't drop for medicines such as blood-thinners, for which marijuana isn't an alternative. The study, which appears in Health Affairs, examined data from Medicare Part D from 2010 to 2013. It is the first study to examine whether legalization of marijuana changes doctors' clinical practice and whether it could curb public health costs. The findings add context to the debate as more lawmakers express interest in medical marijuana. This year, Ohio and Pennsylvania passed laws allowing the drug for therapeutic purposes, making it legal in 25 states, plus Washington, D.C. The approach could also come to a vote in Florida and Missouri this November. A federal agency is considering reclassifying medical marijuana under national drug policy to make it more readily available. © 2016 npr
Keyword: Drug Abuse
Link ID: 22406 - Posted: 07.07.2016
Susan Gaidos By age 25, Patrick Schnur had cycled through a series of treatment programs, trying different medications to kick his heroin habit. But the drugs posed problems too: Vivitrol injections were painful and created intense heroin cravings as the drug wore off. Suboxone left him drowsy, depressed and unable to study or go running like he wanted to. Determined to resume the life he had before his addiction, Schnur decided to hunker down and get clean on his own. In December 2015, he had been sober for two years and had just finished his first semester of college, with a 4.0 grade point average. Yet, just before the holidays, he gave in to the cravings. Settling into his dorm room he stuck a needle in his vein. It was his last shot. Scientists are searching for a different kind of shot to prevent such tragedies: a vaccine to counter addiction to heroin and other opioids, such as the prescription painkiller fentanyl and similar knockoff drugs. In some ways, the vaccines work like traditional vaccines for infectious diseases such as measles, priming the immune system to attack foreign molecules. But instead of targeting viruses, the vaccines zero in on addictive chemicals, training the immune system to usher the drugs out of the body before they can reach the brain. Such a vaccine may have helped Schnur, a onetime computer whiz who grew up in the Midwest, far removed from the hard edges of the drug world. His overdose death reflects a growing heroin epidemic and alarming trend. In the 1960s, heroin was seen as a hard-core street drug abused mostly in inner cities. Now heroin is a problem in many suburban and rural towns across America, where it is used primarily by young, white adults — male and female, according to research published by psychiatrist Theodore Cicero of Washington University in St. Louis and colleagues in 2014 in JAMA Psychiatry. © Society for Science & the Public 2000 - 201
By BENEDICT CAREY New York University’s medical school has quietly shut down eight studies at its prominent psychiatric research center and parted ways with a top researcher after discovering a series of violations in a study of an experimental, mind-altering drug. A subsequent federal investigation found lax oversight of study participants, most of whom had serious mental issues. The Food and Drug Administration investigators also found that records had been falsified and researchers had failed to keep accurate case histories. In one of the shuttered studies, people with a diagnosis of post-traumatic stress caused by childhood abuse took a relatively untested drug intended to mimic the effects of marijuana, to see if it relieved symptoms. “I think their intent was good, and they were considerate to me,” said one of those subjects, Diane Ruffcorn, 40, of Seattle, who said she was sexually abused as a child. “But what concerned me, I was given this drug, and all these tests, and then it was goodbye, I was on my own. There was no follow-up.” It’s a critical time for two important but still controversial areas of psychiatry: the search for a blood test or other biological sign of post-traumatic stress disorder, which has so far come up empty, and the use of recreational drugs like ecstasy and marijuana to treat it. At least one trial of marijuana, and one using ecstasy, are in the works for traumatized veterans, and some psychiatrists and many patients see this work as having enormous promise to reshape and improve treatment for trauma. But obtaining approval to use the drugs in experiments is still politically sensitive. Doctors who have done studies with these drugs say that their uncertain effects on traumatic memory make close supervision during treatment essential. © 2016 The New York Times Company
by German Lopez and Javier Zarracina After years of struggling with treatments for his worsening cancer, Roy was miserable — anxious, depressed, hopeless. Traditional cancer treatments had left him debilitated, and it was unclear whether they would save his life. But then Roy secured a spot in a clinical trial to test an exotic drug. The drug was not meant to cure his cancer; it was meant to cure his terror. And it worked. A few hours after taking a little pill, Roy declared to researchers, "Cancer is not important, the important stuff is love." His concerns about his imminent death had suddenly vanished — and the effects lasted for at least months, according to researchers. It was not a traditional antidepressant, like Zoloft, or anti-anxiety medication, like Xanax, that led Roy to reevaluate his life. It was a drug that has been illegal for decades but is now at the center of a renaissance in research: psilocybin, from hallucinogenic magic mushrooms. Psychologists and psychiatrists have been studying hallucinogens for decades — as treatment for things like alcoholism and depression, and to stimulate creativity. But support for studies dried up in the 1970s, after the federal government listed many psychedelics as Schedule 1 drugs. But now researchers are giving the drugs another look. © 2016 Vox Media, Inc.
By MAIA SZALAVITZ I SHOT heroin and cocaine while attending Columbia in the 1980s, sometimes injecting many times a day and leaving scars that are still visible. I kept using, even after I was suspended from school, after I overdosed and even after I was arrested for dealing, despite knowing that this could reduce my chances of staying out of prison. My parents were devastated: They couldn’t understand what had happened to their “gifted” child who had always excelled academically. They kept hoping I would just somehow stop, even though every time I tried to quit, I relapsed within months. There are, speaking broadly, two schools of thought on addiction: The first was that my brain had been chemically “hijacked” by drugs, leaving me no control over a chronic, progressive disease. The second was simply that I was a selfish criminal, with little regard for others, as much of the public still seems to believe. (When it’s our own loved ones who become addicted, we tend to favor the first explanation; when it’s someone else’s, we favor the second.) We are long overdue for a new perspective — both because our understanding of the neuroscience underlying addiction has changed and because so many existing treatments simply don’t work. Addiction is indeed a brain problem, but it’s not a degenerative pathology like Alzheimer’s disease or cancer, nor is it evidence of a criminal mind. Instead, it’s a learning disorder, a difference in the wiring of the brain that affects the way we process information about motivation, reward and punishment. And, as with many learning disorders, addictive behavior is shaped by genetic and environmental influences over the course of development. Scientists have documented the connection between learning processes and addiction for decades. Now, through both animal research and imaging studies, neuroscientists are starting to recognize which brain regions are involved in addiction and how. © 2016 The New York Times Company
Keyword: Drug Abuse
Link ID: 22365 - Posted: 06.27.2016
By DONALD G. McNEIL Jr. Global health authorities are trying to get more countries to mandate the use of the “world’s ugliest color” on cigarette packaging to discourage smoking. In 2012, GfK Bluemoon, a market research company under contract to the Australian government, announced that nearly 1,000 smokers had voted that a drab greenish brown known as opaque couché, number 448c in the Pantone color matching system, was the world’s most repulsive color. It was described as looking like death, filth, lung tar or baby excrement. Color aficionados later noted that it was also similar to the hue of the dress worn by the Mona Lisa. Photo Cigarettes on sale in Sydney, New South Wales. Credit Ryan Pierse/Getty Images Australia then mandated “plain packaging” for cigarettes that was actually anything but plain. The opaque couché-colored boxes have vivid pictures of rotted teeth, tongues with tumors and dangerously tiny newborns, along with warnings about smoking’s dangers printed in type larger than the brand names. Australia has been very successful in getting smokers to quit, so health officials in Britain, France and Ireland have announced plans to imitate the packaging. Last month, the European Court of Justice rebuffed legal challenges, by tobacco companies, to the use of shocking images, and India’s Supreme Court ruled in favor of letting them cover 85 percent of packs. A recent study in JAMA Internal Medicine found that these pictures prompt more smokers to at least try to quit, but the American tobacco industry has blocked all attempts to put them on cigarette packs sold in the United States. © 2016 The New York Times Company
Keyword: Drug Abuse
Link ID: 22344 - Posted: 06.22.2016
Laurel Hamers People hooked on cocaine are more likely to stick to other habits, too. They’re also less sensitive to negative feedback that tends to push nonaddicts away from harmful habitual behaviors, new research published in the June 17 Science suggests. The findings might help explain why cocaine addicts will do nearly anything to keep using the drug, despite awareness of its negative consequences. Instead, treatments that encourage new, healthier habits in place of drug use might click better. Similar results have been demonstrated with mice and rats, but the effect hadn’t been well-established in humans. There’s no pharmacological treatment approved by the U.S. Food and Drug Administration that targets cocaine addiction as there is for opioid addiction. So the best treatment currently focuses on changing patients’ behavior — and it’s not easy. “It’s such a devastating situation for families,” says Karen Ersche, a psychologist at the University of Cambridge who led the study. Drug users “know they’ll lose their job. They’ll tell you they want to change, but still they carry on using the drug. It seems incomprehensible.” Habits can be helpful because they free up brainpower for other things. A new driver has to think through every push of the pedal and flick of the turn signal, while an experienced one can perform these actions almost effortlessly, allowing them to also carry on a conversation. But people can also snap out of that automation when necessary, slamming on the brakes when a deer darts across the road. It’s harder for someone addicted to cocaine to get off autopilot. © Society for Science & the Public 2000 - 2016.
Keyword: Drug Abuse
Link ID: 22340 - Posted: 06.20.2016
By Jane E. Brody Smokers who think they are escaping the lung-damaging effects of inhaled tobacco smoke may have to think again, according to the findings of two major new studies, one of which the author originally titled “Myth of the Healthy Smoker.” Chronic obstructive pulmonary disease, or C.O.P.D., may be among the best known dangers of smoking, and current and former smokers can be checked for that with a test called spirometry that measures how much air they can inhale and how much and how quickly they can exhale. Unfortunately, this simple test is often skipped during routine medical checkups of people with a history of smoking. But more important, even when spirometry is done, the new studies prove that the test often fails to detect serious lung abnormalities that cause chronic cough and sputum production and compromise a person’s breathing, energy level, risk of serious infections and quality of life. “Current or former smokers without airflow obstruction may assume that they are disease-free,” but that’s not necessarily the case, one of the research teams pointed out. These researchers projected that there are 35 million current or former smokers older than 55 in the United States with unrecognized smoking-caused lung disease or impairments. Many, if not most, of these people could get worse with time, even if they have quit smoking. They are also unlikely to be referred for pulmonary rehabilitation, a treatment that can head off encroaching disability. Perhaps most important, those currently smoking may be inclined to think they’ve dodged the bullet and so can continue to smoke with impunity. Doctors, who are often reluctant to urge patients with symptoms to quit smoking, may be even less likely to recommend smoking cessation to those with normal spirometry results. Referring to C.O.P.D., one of the researchers, Dr. Elizabeth A. Regan, said, “Smoking is really taking a terrible toll on our society.” Dr. Regan, a clinical researcher at National Jewish Health in Denver, is the lead author of one of the new studies, published last year in JAMA Internal Medicine. “We live happily in the world thinking that only a small percentage of people who smoke get this devastating disease,” she said. “However, the lungs of millions of people in the United States are negatively impacted by smoking, and our methods for identifying their lung disease are relatively insensitive.” © 2016 The New York Times Company
Keyword: Drug Abuse
Link ID: 22339 - Posted: 06.20.2016
By Brady Dennis In one city after another, the tests showed startling numbers of children with unsafe blood lead levels: Poughkeepsie and Syracuse and Buffalo. Erie and Reading. Cleveland and Cincinnati. In those cities and others around the country, 14 percent of kids — and in some cases more — have troubling amounts of the toxic metal in their blood, according to new research published Wednesday. The findings underscore how despite long-running public health efforts to reduce lead exposure, many U.S. children still live in environments where they're likely to encounter a substance that can lead to lasting behavioral, mental and physical problems. "We've been making progress for decades, but we have a ways to go," said Harvey Kaufman, senior medical director at Quest Diagnostics and a co-author of the study, which was published in the Journal of Pediatrics. "With blood [lead] levels in kids, there is no safe level." Kaufman and two colleagues at Quest, the nation's largest lab testing provider, examined more than 5.2 million blood tests for infants and children under age 6 that were taken between 2009 and 2015. The results spanned every state and the District of Columbia. The researchers found that while blood lead levels declined nationally overall during that period, roughly 3 percent of children across the country had levels that exceed five micrograms per deciliter — the threshold that the Centers for Disease Control and Prevention considers cause for concern. But in some places and among particular demographics, those figures are much higher.
By Brian Platzer It started in 2010 when I smoked pot for the first time since college. It was cheap, gristly weed I’d had in my freezer for nearly six years, but four hours after taking one hit I was still so dizzy I couldn’t stand up without holding on to the furniture. The next day I was still dizzy, and the next, and the next, but it tapered off gradually until about a month later I was mostly fine. Over the following year I got married, started teaching seventh and eighth grade, and began work on a novel. Every week or so the disequilibrium sneaked up on me. The feeling was one of disorientation as much as dizziness, with some cloudy vision, light nausea and the sensation of being overwhelmed by my surroundings. During one eighth-grade English class, when I turned around to write on the blackboard, I stumbled and couldn’t stabilize myself. I fell in front of my students and was too disoriented to stand. My students stared at me slumped on the floor until I mustered enough focus to climb up to a chair and did my best to laugh it off. I was only 29, but my father had had a benign brain tumor around the same age, so I had a brain scan. My brain appeared to be fine. A neurologist recommended I see an ear, nose and throat specialist. A technician flooded my ear canal with water to see if my acoustic nerve reacted properly. The doctor suspected either benign positional vertigo (dizziness caused by a small piece of bonelike calcium stuck in the inner ear) or Ménière’s disease (which leads to dizziness from pressure). Unfortunately, the test showed my inner ear was most likely fine. But just as the marijuana had triggered the dizziness the year before, the test itself catalyzed the dizziness now. In spite of the negative results, doctors still believed I had an inner ear problem. They prescribed exercises to unblock crystals, and salt pills and then prednisone to fight Ménière’s disease. All this took months, and I continued to be dizzy, all day, every day. It felt as though I woke up every morning having already drunk a dozen beers — some days, depending on how active and stressful my day was, it felt like much more. Most days ended with me in tears. © 2016 The New York Times Company
[Agata Blaszczak-Boxe, Contributing Writer] People who use marijuana for many years respond differently to natural rewards than people who don't use the drug, according to a new study. Researchers found that people who had used marijuana for 12 years, on average, showed greater activity in the brain's reward system when they looked at pictures of objects used for smoking marijuana than when they looked at pictures of a natural reward — their favorite fruits. "This study shows that marijuana disrupts the natural reward circuitry of the brain, making marijuana highly salient to those who use it heavily," study author Dr. Francesca Filbey, an associate professor of behavioral and brain science at the University of Texas at Dallas, said in a statement. "In essence, these brain alterations could be a marker of transition from recreational marijuana use to problematic use." [11 Odd Facts About Marijuana] In the study, researchers looked at 59 marijuana users who had used marijuana daily for the past 60 days, and had used the drug on at least 5,000 occasions during their lives. The researchers wanted to see whether the brains of these long-term marijuana users would respond differently to picures of objects related to marijuana use than they did to natural rewards, such as their favorite fruits, compared with people who did not use marijuana.
Keyword: Drug Abuse
Link ID: 22317 - Posted: 06.14.2016
By Monique Brouillette The brain presents a unique challenge for medical treatment: it is locked away behind an impenetrable layer of tightly packed cells. Although the blood-brain barrier prevents harmful chemicals and bacteria from reaching our control center, it also blocks roughly 95 percent of medicine delivered orally or intravenously. As a result, doctors who treat patients with neurodegenerative diseases, such as Parkinson's, often have to inject drugs directly into the brain, an invasive approach that requires drilling into the skull. Some scientists have had minor successes getting intravenous drugs past the barrier with the help of ultrasound or in the form of nanoparticles, but those methods can target only small areas. Now neuroscientist Viviana Gradinaru and her colleagues at the California Institute of Technology show that a harmless virus can pass through the barricade and deliver treatment throughout the brain. Gradinaru's team turned to viruses because the infective agents are small and adept at entering cells and hijacking the DNA within. They also have protein shells that can hold beneficial deliveries, such as drugs or genetic therapies. To find a suitable virus to enter the brain, the researchers engineered a strain of an adeno-associated virus into millions of variants with slightly different shell structures. They then injected these variants into a mouse and, after a week, recovered the strains that made it into the brain. A virus named AAV-PHP.B most reliably crossed the barrier. © 2016 Scientific American,
Link ID: 22313 - Posted: 06.13.2016
By JOHN ELIGON and SERGE F. KOVALESKI Prince, the music icon who struggled with debilitating hip pain during his career, died from an accidental overdose of self-administered fentanyl, a type of synthetic opiate, officials in Minnesota said Thursday. The news ended weeks of speculation about the sudden death of the musician, who had a reputation for clean living but who appears to have developed a dependency on medications to treat his pain. Authorities have yet to discuss how he came to be in possession of the fentanyl and whether it had been prescribed by a doctor. Officials had waited several weeks for the results of a toxicology test undertaken as part of an autopsy performed after he was found dead April 21 in an elevator at his estate. He was preparing to enroll in an opioid treatment program when he died at 57, according to the lawyer for a doctor who was planning to treat him. The Midwest Medical Examiner’s Office, which conducted the autopsy, declined to comment beyond releasing a copy of its findings. The Carver County Sheriff’s Office is continuing to investigate the death with help from the federal Drug Enforcement Administration. The sheriff’s office had said it was looking into whether opioid abuse was a factor, and a law enforcement official had said that painkillers were found on Prince when investigators arrived. “The M.E. report is one piece of the whole thing,” said Jason Kamerud, the county’s chief deputy sheriff. Fentanyl is a potent but dangerous painkiller, estimated to be more than 50 times more powerful than heroin, according to the Centers for Disease Control and Prevention. The report did not list how much fentanyl was found in Prince’s blood. Last year, federal officials issued an alert that said incidents and overdoses with fentanyl were “occurring at an alarming rate throughout the United States.” © 2016 The New York Times Company