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Showing posts from September, 2017

What makes alcoholics drink? Research shows it's more complex than supposed

This work once again shows that alcoholism is not a one-size-fits-all condition," said lead researcher, Victor Karpyak (Mayo Clinic, MN, USA). "So the answer to the question of why alcoholics drink is probably that there is no single answer; this will probably have implications for how we diagnose and treat alcoholism." The work, presented at the ECNP congress by researchers from the Mayo Clinic*, determined the alcohol consumption of 287 males and 156 females with alcohol dependence over the previous 90 days, using the accepted Time Line Follow Back method and standardized diagnostic assessment for life time presence of psychiatric disorders (PRISM); they were then able to associate this with whether the drinking coincided with a positive or negative emotional state (feeling "up" or "down"), and whether the individual had a history of anxiety, depression (MDD) or substance abuse. The results showed that alcohol dependent men tended to drink mo...

Do we need to reform international drug treaties as more countries legalize cannabis?

The international drug control treaties are endorsed by most member states of the United Nations (UN). The treaties prohibit the non-medical use of amphetamines, cannabis, cocaine and heroin. They aim to reduce the harmful use of prohibited drugs and facilitate access to these drugs for medical and scientific purposes. Critics claim that the treaties have failed to tackle non-medical use of prohibited drugs and have justified policies that conflict with UN human rights treaties by incarcerating large numbers of drug users. Hall's paper outlines types of policies that nations could adopt to address the different types of harm that different illicit drugs cause to users and others. Some would require treaty change, while others could be accomplished by more 'flexible interpretations' of treaty provisions by member states and UN agencies. His suggestions are: Cannabis:  This is the strongest candidate for national policy experiments on different ways of regulating its ...

E-cigarettes linked to increased arterial stiffness, blood pressure and heart rate in humans

Presenting the research at the Europea n Respiratory Society I nternational Congress today (Monday), Dr Magnus Lundbäck said: "The number of e-cigarette users has increased dramatically in the last few years. E-cigarettes are regarded by the general public as almost harmless. The e-cigarette industry markets their product as a way to reduce harm and to help people to stop smoking tobacco cigarettes. However, the safety of e-cigarettes is debated, and a growing body of evidence is suggesting several adverse health effects. "The results are preliminary, but in this study we found there was a significant increase in heart rate and blood pressure in the volunteers who were exposed to e-cigarettes containing nicotine. Arterial stiffness increased around three-fold in those who were exposed to nicotine containing e-cigarettes compared to the nicotine-free group." Dr Lundbäck (MD, PhD), who is a research leader and clinical registra r at the Danderyd University Hospital, ...

Cocaine users' brains unable to extinguish drug associations

Their study, published September 5 in  Addiction Biology , finds that chronic users have a "global impairment" in the ventromedial prefrontal cortex (VMPFC), an area of the brain that is linked to impulse and self-control, and is responsible for the kind of learning that assigns value to objects and behaviors. The Mount Sinai study investigated a specific type of learning called extinction -- the process by which a new, affectively neutral, association replaces an old, affectively arousing association -- to identify the neurobiological mechanism that underlies the persistence of drug seeking in addiction despite negative consequences and a reduction in the drug's rewarding affects. To investigate these questions, the research team collected functional magnetic resonance imaging (fMRI) data on a three-phase classical conditioning paradigm in individuals with a history of chronic cocaine use and healthy control individuals without the drug habit. They found that in dr...

Running group helps half its graduates quit smoking

This shows that physical activity can be a successful smoking-cessation aid and that a community-based program might offer that. Because doing it on your own is very difficult," said Carly Priebe, postdoctoral fellow in UBC's school of kinesiology and lead author of the study. One hundred and sixty-eight smokers from across Canada registered for the 2016 Run to Quit program at Running Room stores, and 72 of them stuck it out until the final week, when 37 participants had their claims of quitting verified by carbon-monoxide testing. The number of successful quitters held up during follow-up interviews six months later. The group that finished the program also included 91 per cent who reported reducing their smoking. The weekly sessions included classroom time divided between running instruction and strategies for quitting smoking, plus an outdoor walking/running component that progressed toward a five-kilometre run. Participants had access throughout the program to one-o...

Reversing the negative effects of adolescent marijuana use

"What is important about this study is that not only have we identified a specific mechanism in the prefrontal cortex for some of the mental health risks associated with adolescent marijuana use, but we have also identified a mechanism to reverse those risks," said Steven Laviolette, professor at Western's Schulich School of Medicine & Dentistry. In a study published online today in  Scientific Reports  the researchers demonstrate that adolescent THC exposure modulates the activity of a neurotransmitter called GABA in the prefrontal cortex region of the brain. The team, led by Laviolette and post-doctoral fellow Justine Renard, looked specifically at GABA because of its previously shown clinical association with schizophrenia. "GABA is an inhibitory neurotransmitter and plays a crucial role in regulating the excitatory activity in the frontal cortex, so if you have less GABA, your neuronal systems become hyperactive leading to behavioural changes consiste...

Marijuana may produce psychotic-like effects in high-risk individuals

The study was published last month in an online edition of  Psychiatry Research . Individuals who have had mild or transient psychotic symptoms (such as unusual thoughts, suspiciousness, perceptual disturbances) without using substances such as marijuana or alcohol and have a family history of psychosis or other risk factors are considered at clinical high risk for psychotic disorder. Previous studies have found an association between marijuana use and psychosis in the general population, but none have rigorously examined marijuana's effects in those at greatest risk for psychosis. "Many adolescents and young adults who are at high risk for psychosis smoke marijuana regularly or have a cannabis use disorder," said Margaret Haney, PhD, professor of neurobiology (in Psychiatry) at CUMC and senior author of the paper. "Yet researchers haven't studied the effects of marijuana in this population in a rigorous, controlled manner." In this double-blinded,...

Young binge drinkers show altered brain activity

For many students, college involves a lot of socializing at parties and at bars, and alcohol is a common factor in these social environments. Excessive alcohol use, in the form of binge drinking, is extremely common among college students, and one study has estimated that as many as one third of young North Americans and Europeans binge drink. So, what defines binge drinking? The National Institute of Alcohol Abuse and Alcoholism describes a binge as drinking five or more drinks for men and four or more for women within a two-hour period, and for many college students, these limits wouldn't equate to a particularly heavy night. Previous research has linked binge drinking to a variety of negative consequences including neurocognitive deficits, poor academic performance, and risky sexual behavior. While numerous studies have shown that the brains of chronic alcoholics have altered brain activity, there is also evidence that bingeing can change adolescents' brains. Eduar...

Medical students not trained to prescribe medical marijuana

Their findings are available online in the journal  Drug and Alcohol Dependence . "Medical education needs to catch up to marijuana legislation," said senior author Laura Jean Bierut, MD, the Alumni Endowed Professor of Psychiatry at Washington University and a member of the National Advisory Council on Drug Abuse. "Physicians in training need to know the benefits and drawbacks associated with medical marijuana so they know when or if, and to whom, to prescribe the drug." Doctors are being asked to guide patients through areas in which most have no training, she explained. The research team, led by first author Anastasia B. Evanoff, sent surveys to medical school curriculum deans at 172 medical schools in North America, including 31 that specialize in osteopathic medicine, and received 101 replies. Two-thirds (66.7 percent) reported that their graduates were not prepared to prescribe medical marijuana. A quarter of deans said their trainees weren't eve...

Immune system linked to alcohol drinking behavior

In laboratory studies using mice, researchers have been able to switch off the impulse to drink alcohol by giving mice a drug that blocks a specific response from the immune system in the brain. Now published in the journal  Brain, Behavior and Immunity , this research is one of the first of its kind to show a link between the brain's immunity and the motivation to drink alcohol at night. "Alcohol is the world's most commonly consumed drug, and there is a greater need than ever to understand the biological mechanisms that drive our need to drink alcohol," says lead author Jon Jacobsen, PhD student in the University of Adelaide's Discipline of Pharmacology. "Our body's circadian rhythms affect the 'reward' signals we receive in the brain from drug-related behavior, and the peak time for this reward typically occurs during the evening, or dark phase. We wanted to test what the role of the brain's immune system might have on that reward,...