Алкоголизм, наркомания, порнозависимость - а с мозгом что?

Отличная статья о разнице в функционировании мозга при наличии зависимостей разного рода. Алкоголь, никотин, психотропные вещества всяческой природы, еда, порно или азартные игры - всё это приносит удовольствие в момент присутствия и боль при отсутствии. Но много ли общего в формировании звисимостей от разных факторов?
Вот и рассуждения на эту увлекательную тему - https://www.sciencenews.org/blog/scicurious/addiction-showcases-brain-flexibility

Очередные новости об избавлении от опиатной зависимости

Действительно интересно. оказывается, на подходе очередное средство борьбы с героиновой и морфиновой наркоманией. Более того, учёные утверждают, что с помощью новейших подходов можно не только избавиться от зависимости, но и не страдать от болезненных ощущений. Подробности:

Unlike the heroin-specific vaccine we covered last year, an international team of scientists from the University of Adelaide in Australia and the University of Colorado Boulder has now found a way to block addiction to various opioid drugs, including heroin and morphine. Importantly, the new approach doesn’t negatively affect the pain-relieving properties of these drugs.
The central nervous system and the immune system both play important roles in the development of an addiction, with opioid drugs such as heroin and morphine binding to an immune receptor known as Toll-like receptor 4 (TLR4) in a similar way to the normal immune response to bacteria. Dr. Mark Hutchinson, ARC Research Fellow in the University of Adelaide’s School of Medical Sciences says, “The problem is that TLR4 then acts as an amplifier for addiction.”
In studies on rats using (+)-naloxone, a drug that automatically shuts down the opioid addiction by altering brain chemistry to stop production of the feel-good chemical dopamine, the researchers found that blocking the immune response is all that is required to prevent cravings for opioid drugs.
“Our studies have shown conclusively that we can block addiction via the immune system of the brain, without targeting the brain’s wiring,” said Hutchinson, who was lead author of the study.
“This work fundamentally changes what we understand about opioids, reward and addiction,” adds senior author Professor Linda Watkins, from the Center for Neuroscience at CU-Boulder. “We’ve suspected for some years that TLR4 may be the key to blocking opioid addiction, but now we have the proof.
“The drug that we’ve used to block addiction, (+)-naloxone, is a non-opioid mirror-image drug that was created by Dr. Kenner Rice in the 1970s,” Watkins said. “We believe this will prove extremely useful as a co-formulated drug with morphine, so that patients who require relief for severe pain will not become addicted but still receive pain relief. This has the potential to lead to major advances in patient and palliative care.”
The researchers say clinical trials may be possible within the next 18 months.
The results of their study are being published in the August 15 edition of the Journal of Neuroscience.
Source: University of Adelaide

За инфу спасибо http://www.gizmag.com/opioid-addiction-immune-system/23706/ 

Опять результаты исследований эффектов экстази

Ну, в общем, читайте: экстази и память, некоторые новые данные.

Though ecstasy is known to cause health risks such as depression, sleep problems, severe anxiety and increasing other drug cravings, there has been a considerable amount of debate questioning whether or not government officials have over-reacted to ecstasy.

Опиаты более страшны для людей с психическими проблемами

С праздничками, коллеги!
Вот вам свежая новость от капитана Очевидность.

Оказывается, люди с психическими расстройствами (биполярный психоз, депрессия и т.д.) более подвержены зависимости от опиатов. Полный текст на http://www.biologynews.net/archives/2011/12/13/opioid_abuse_linked_to_mood_and_anxiety_disorders_.html
Да вы что!1111111111111 Оо

Эффекты разных психоактивных веществ на уровне синапсов

Простенько, но со вкусом.
http://faculty.plattsburgh.edu/donald.slish/DA.html

Хроническое употребление кетамина разрушает клетки мочевого пузыря

Chronic ketamine use kills bladder cells - health - 15 June 2011 - New Scientist - статейка о новом исследовании о вреде кетамина, который раньше массово использовали для наркоза, а совсем недавно предлагали использовать как антидепрессант даже для лечения детей (в минимальных дозах). Внезапно оказалось, что это вещество способно необратимо изменять состояние клеток мочевого пузыря.

Допаминово-серотониновые новости :)

Пабмед принёс новую пачку статей о допаминергической и серотонинергической системах:

Neuropharmacology. 2011 Apr 12.
Enhanced effects of amphetamine but reduced effects of the hallucinogen, 5-MeO-DMT, on locomotor activity in 5-HT(1A) receptor knockout mice: Implications for schizophrenia.

van den Buuse M, Ruimschotel E, Martin S, Risbrough VB, Halberstadt AL.

Behavioural Neuroscience Laboratory, Mental Health Research Institute, Parkville, Melbourne, Australia; Department of Pharmacology, University of Melbourne, Australia.

Neuropharmacology. 2011 Apr 15.
Possible involvement of serotonin 5-HT2 receptor in the regulation of feeding behavior through the histaminergic system.

Murotani T, Ishizuka T, Isogawa Y, Karashima M, Yamatodani A.

Department of Medical Science and Technology, Division of Health Sciences, Graduate School of Medicine, Osaka University, 1-7 Yamadaoka, Suita, Osaka 565-0871, Japan.

Neuropharmacology. 2011 Apr 17.
Differential effects of cocaine and MDMA self-administration on cortical serotonin transporter availability in monkeys.

Gould RW, Gage HD, Banks ML, Blaylock BL, Czoty PW, Nader MA.

Department of Physiology and Pharmacology, Wake Forest University School of Medicine, Winston-Salem, NC 27157, United States.

Neuropharmacology. 2011 Apr 19.
Dopamine-related drugs act presynaptically to potentiate GABA(A) receptor currents in VTA dopamine neurons.

Michaeli A, Yaka R.

Institute for Drug Research, School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel.

Neuropharmacology. 2011 Apr 7.
High concentrations of MDMA ('ecstasy') and its metabolite MDA inhibit calcium influx and depolarization-evoked vesicular dopamine release in PC12 cells.

Hondebrink L, Meulenbelt J, Meijer M, van den Berg M, Westerink RH.

Neurotoxicology Research Group, Institute for Risk Assessment Sciences (IRAS), Utrecht University, P.O. Box 80.177, NL-3508 TD Utrecht, The Netherlands; National Poisons Information Centre (NVIC), National Institute for Public Health and the Environment (RIVM), P.O. Box 1, NL-3720 BA, Bilthoven, The Netherlands.

Передозировки лекарствами

Оказывается, в США существует проблема, выходящая на уровень эпидемии.
Подробнее об этом в статье: Narcotic pain relief drug overdose deaths a national epidemic  

О лечении пристрастия к кокаину

Радикальный метод - прямое влияние на мозг:

Статья опубликована в  http://blog.the-scientist.com/2011/02/15/cocaine/ By Cathryn Denney

It’s clearly no longer just the drug of the young, rich and trendy: a decrease in street value over the years has led to a marked rise in usage and availability of cocaine, and it’s an ever-present favourite with the media. The BBC news website alone has dozens of cocaine-related news results since the beginning of the year (who knew the Highland Games were such a rave!).

The short lived euphoric effects of cocaine and subsequent come down lead to a physical and psychological addiction that cause a user to increase their frequency of intake. Using rats that could self-administer cocaine, Christelle Baunez and colleagues at the French National Center for Scientific Research looked at the effects of lesions in the subthalamic nucleus (STN) on addiction.
Following on from earlier work demonstrating that deep brain stimulation of the STN can reduce motivation of rats to work to get the drug¹, but increase motivation to work for food, they tested the hypothesis that lesions in the STN could prevent an escalation in cocaine intake. As described in a poster presented at the Neuroscience 2010 meeting, they found that treated rats decreased the number of times they helped themselves to cocaine, but with no ill effects on memory or locomotion.
“This has potential implications for the treatment of addicts,” suggests F1000 Section Head Trevor W. Robins of the University of Cambridge, in his evaluation of the poster. Baunez adds, “Before translating it to human addicts, the best thing will be to test the effects of STN inactivation in monkeys, which is one of our plans for the future.”

Дым сигарет с ментолом

Интересная инфа о влиянии ментола на "привыкабельность":
Cigarettes are just plain bad, as we all know by now.
But what about the ones that contain menthol? Are they worse?
A panel of experts is mulling menthol and trying to come up with some advice for the Food and Drug Administration on whether menthol should be forbidden as an additive.
Young people seem to gravitate to menthol-flavored cigarettes, and there's evidence menthol may make it harder for smokers trying to quit. It turns out that tiny amounts of menthol are even added as a subtle flavor-enhancer to many cigarettes that aren't labeled as menthol types.
Should menthol be banned —- just as Congress has banned other flavorings in cigarettes? Tobacco industry representatives say taste is the only thing that distinguishes menthol cigarettes from regular one — they aren't more harmful.
The use of menthol started accidentally, after mint crystals got left in a smoker’s tin of rolling tobacco overnight years ago.
The mint in menthol cigarettes may be natural or synthetic or a combination of both. Natural mint is crystalized from steamed distilled oil of the corn mint plant. Some 99 percent of the mint comes through in the smoke.
So how does the stuff get put on cigarettes? A bunch of ways. Sometimes, it's applied to the foil that is used to wrap the cigarettes. It's also sprayed on the tobacco, and even injected into the tobacco paper or the filter.
After a few weeks for aging, Michael Ogden of R.J. Reynolds says the effect was found to be the same pretty much regardless of method, according to smokers who volunteered for taste tests.
Ogden says testers describe the menthol smokes using terms like "cooling sensation, minty flavor and medicinal flavor."
Menthol can be misleading. "Menthol leads to the perception of an increase in nasal airway openness but in fact there is no actual change and (some studies have shown) minor constriction," Ogden says
R.J. Reynolds is the maker of Kool and Salem, once the leading menthol brands. Now, Newport dominates the market. It's from Lorillard, whose Scientific Director William True can sound like someone on Top Chef when he describes how the company assesses menthol.
True says the company taste experts sample packs the way some people test fine wine. They are sensitive to such things as a cigarette's early draw, the tobacco's papery or woody flavors, whether it's bitter or sweet, has a later draw or an after taste.
But it isn't menthol's taste that is under scrutiny at the hearing.
The scientific advisory panel wanted to know what properties in mentholated cigarettes attract young people, African Americans, and other ethnic groups. Newport is the top menthol cigarette for adolescents, according to the federal Substance Abuse & Mental Health Services Administration. The thinking is that menthol mellows the harshness of tobacco, which makes it easier for initiates to inhale and others to inhale more deeply.
True objected strenuously. "Absolutely not," he says. "Our product developers do not use menthol in any shape or form to cover, mask or minimize that harsh taste. The most significant items that impact the harsh taste of the cigarette are the tobacco blend, the moisture level of the blend and the filter ventilation."
The manufacturers of menthol cigarettes also deny that young people and ethnic groups are targeted with promotions. Industry representatives couldn't explain why menthol smokers tend to smoke fewer cigarettes, or why cancer rates are higher among African American smokers 70 percent of whom smoke menthol but smoke fewer cigarettes per day than non-menthol smokers.
"Internal studies do not indicate that menthol cigarettes are smoked any differently or more intensely than non menthol," according to Lorillard's William True. "These studies reinforce the overwhelming weight of epidemiology literature that menthol and non menthol convey similar risk of chronic disease."
Прочитано на http://www.npr.org/blogs/health/2010/07/16/128563062/menthol-the-mystery-ingredient-in-cigarettes

Может ли метамфетамин улучшить память?

Нет, скорее, он может ухудшить забывание, - пишут на http://www.eurekalert.org/pub_releases/2010-05/tcob-som052010.php
Snails on methamphetamine


How methamphetamine improves snail's memory

Crystal meth (methamphetamine) is a highly addictive drug that seduces victims by increasing self-esteem and sexual pleasure, and inducing euphoria. But once hooked, addicts find the habit hard to break. Barbara Sorg from Washington State University, USA, explains that amphetamines enhance memory. 'In addiction we talk about the "drug memory" as a "pathological memory". It is so potent as to not be easily forgotten,' she explains. As memory plays an important role in addiction, Sorg wondered whether it might be possible to find out more about the effects of meth on memory by looking at the effect it has on a humble mollusc: the pond snail Lymnaea stagnalis.
Lymnaea hold memories about when to breathe through their breathing tubes (pneumostomes) in a three neuron network, which is much simpler than the colossal circuits that hold our memories. Ken Lukowiak from University of Calgary, Canada, has been working on the mechanisms of memory formation in these snails for most of his career, so he and Sorg decided to team up to find out whether a dose of meth could improve the snails' memories in the way it does human memories. They publish their discovery that memories formed by snails under the influence of meth are harder to forget, which could help us to understand human addiction, on 28 May 2010 in The Journal of Experimental Biology at http://jeb.biologists.org/.
First Sorg and her students had to discover whether a dose of meth could affect the snails' breathing behaviour. According to Lukowiak, the snails breathe through their skins when oxygen levels are high, but when oxygen levels drop the snails extend their pneumostomes above the water's surface to supplement the supply. As the drug easily crosses the snail's skin, the team immersed the snails in de-oxygenated pond water spiked with meth, and watched to see how it affected their breathing. The snails stopped raising their pnemostomes at 1 and 3.3·μmol·l-1 meth, so having found a dose that altered the snail's behaviour, the team began testing its effects on the mollusc's long term memory.
The team trained the snails to remember to keep their pneumostomes closed when oxygen levels were low by poking them with a stick every time they tried to open their pneumostomes. Giving the snails two training sessions separated by an hour, the team knew that the molluscs would hold the memory for over 24·h, but what would happen if they trained the snails in meth-laced water?
Testing the snails in de-oxygenated pond water 24 hours later, the team were surprised to see that the snails seemed to have no recollection of their training, popping their pneumostomes above the water's surface. Maybe meth did not affect the snails' memories. But then Lukowiak remembered: 'If you put snails in a novel context even though they have memory they respond as if they don't have memory,' he says. Without meth in the water, the snails were ignoring their memory. However, when the team reintroduced meth to the test water, the snails suddenly remembered to keep their pneumostomes closed. This could explain why it's so hard for human addicts to kick the habit when returning to old haunts that trigger the addiction memory.

Next the team wondered whether meth could improve the snails' memories. First they immersed the snails in meth-laced pond water, then they moved them into regular de-oxygented pond water and gave them a training session that the snails should only recall for a few hours. In theory the snails should have forgotten their training 24 hours later, but would the meth improve the snails' memories so they remembered to keep their pneomostomes closed a day later? It did. A dose of meth prior to training had improved the snails' memories, allowing them to recall a lesson that they should have already forgotten. And when the team tested whether they could mask the meth memory with another memory, they found that the meth memory was much stronger and harder to mask.

So memories formed under the influence of meth seem to be harder to forget, possibly because the drug disrupts the mechanisms for forgetting, and could help us to understand how amphetamines enhance memory in humans.


###

IF REPORTING ON THIS STORY, PLEASE MENTION THE JOURNAL OF EXPERIMENTAL BIOLOGY AS THE SOURCE AND, IF REPORTING ONLINE, PLEASE CARRY A LINK TO: http://jeb.biologists.org/

REFERENCE: Kennedy, C. D., Houmes, S. W., Wyrick, K. L., Kammerzell, S. M., Lukowiak, K. and Sorg, B. A. (2010). Methamphetamine enhances memory of operantly conditioned respiratory behavior in the snail Lymnaea stagnalis. J. Exp. Biol. 213, 2055-2065.

This article is posted on this site to give advance access to other authorised media who may wish to report on this story. Full attribution is required, and if reporting online a link to jeb.biologists.com is also required. The story posted here is COPYRIGHTED. Therefore advance permission is required before any and every reproduction of each article in full. PLEASE CONTACT permissions@biologists.com

THIS ARTICLE APPEARS IN THE JOURNAL OF EXPERIMENTAL BIOLOGY ON: 28 May 2010. EMBARGOED UNTIL THURSDAY, 27 May 2010, 17:00 HRS EST

Солярий = наркотик?

Очень классное исследование показывает, что между посещением соляриев и склонностью к зависимостям, в том числе и наркотической, есть прямая связь. Материал с http://blisstree.com/feel/white-hot-addiction-skin-cancer-and-the-tanning-bed/:
Even though the 80s are long gone, tanning bed addiction is alive and well, a recent study suggests. Fake rays are like crack for some UV bed frequenters.
Researchers decided to examine a link from tanning to substance abuse and depression in college students, and found that among 229 of them, 90 qualified as “addicted to indoor tanning.” And those addicts reported greater symptoms of anxiety and more drug and alcohol use.
Heavy tanners actually missed going outside to catch the sun’s natural rays. More than 3/4 of the most frequent tanners tried to cut down on indoor tanning sessions, but had been unable to, according to The New York Times.
How can a person be addicted to a neon blue lit coffin? As with exercise, research suggests that UV rays may release endorphins. And even though everyone in the study knew the health risks involved with tanning, it seems that – for some people – achieving that golden goddess glow might be worth a little skin cancer.

О вреде кокаина и метамфетамина

2 новых статьи:
http://www.eurekalert.org/pub_releases/2010-03/uoc--sdi031710.php - о том, что при повышенной температуре  воздуха, риск негативного влияния кокаина на организм увеличивается

http://www.eurekalert.org/pub_releases/2010-03/sfn-bai031210.php - о страшных последствиях употребления метамфетамина матерями.

Три новых статьи об эффектах наркотических веществ

http://scienceblogs.com/drugmonkey/2010/02/synthetic_marijuana_k2_spice_j.php - о синтетической марихуане
http://www.scientificblogging.com/news_articles/does_recreational_drug_use_damage_memory - о проблемах с памятью у употребляющих психотропные вещества
http://scienceblogs.com/drugmonkey/2010/02/as_many_dependent_on_cannabis.php - о связи курения марихуаны и употребления героина

Средство борьбы с кокаином!

Интересные новости. Новый способ борьбы с кокаиновой зависимостью описан на http://www.eurekalert.org/pub_releases/2010-01/fo1b-ana122309.php:
A new ally in the battle against cocaine addiction


A recent study shows that a bacterial protein may help cocaine addicts break the habit.
Cocaine esterase (CocE) is a naturally-occurring bacterial enzyme that breaks down cocaine, thereby reducing its addictive properties. The efficacy of CocE in animals and its suitability for treatment of addiction has been limited by its short half-life in the body.

A recent study, published in the Journal of Pharmacology and Experimental Therapeutics and reviewed by Faculty of 1000 Medicine's Friedbert Weiss, demonstrates that a more stable version of CocE, double mutant or DM CocE, significantly decreased the desire for cocaine and prevented death from cocaine overdose.
In the study, rats were trained to self-administer cocaine by pressing a button in their cage, mimicking the need for regular doses of the drug during addiction. Rats treated with the double mutant form of CocE pressed the button to receive cocaine less often, suggesting that DM-CocE broke down the drug and dampened addiction.

DM-CocE decreased the rats' urge for cocaine but not for an addictive analogue, highlighting the degree of specificity for cocaine. Weiss notes that the DM-CocE enzyme also provides "long-lasting protection" against the toxic effects of a potentially lethal dose.

Though the effects of CocE can be overcome by a sufficiently large dose of cocaine, the present findings suggest that CocE has great promise as a drug abuse treatment.
Weiss says, "These therapeutic approaches may therefore not be "fail-safe" for reducing cocaine intake by determined users" but "long-acting forms of CocE represent potentially valuable treatment approaches not only for the prevention of cocaine-induced toxicity but also for ongoing cocaine abuse in humans."

Что думают наркоманы?

Интересно о мнениях наркоманов о том, что они употребляют. Что опаснее - легальные или нелегальные вещества? Читаем: http://www.eurekalert.org/pub_releases/2009-11/ucl-duk112309.php
Drug users know their stuff

Drug users are well informed about the harms associated with the drugs they use, and perceive alcohol and tobacco to be amongst the most dangerous substances, according to a survey by UCL (University College London) and Imperial College London researchers. The findings, published in the Journal of Psychopharmacology, suggest that the current system of classifying psychoactive drugs in the UK may need to be revisited.

The study, led by Dr Celia Morgan and Professor Valerie Curran at UCL, surveyed 1,500 UK drug users via the website www.nationaldrugsurvey.org. Drug users were asked to rate twenty psychoactive substances on a 'rational' scale previously developed by Professor David Nutt, Imperial College London, who collaborated on this study. Heroin, crack and cocaine topped the list in terms of harm, but alcohol was rated fifth, solvents seventh and tobacco ninth. Ecstasy came 13th in the harm rating, LSD 16th and cannabis 18th. Thus, the survey found no relationship between the drug's legal status, based on the current classification system, and users' ratings of harm. In the UK, the Misuse of Drugs Act (1971) currently classifies psychoactive drugs as A, B or C, though alcohol and tobacco remain unclassified.

Dr Celia Morgan, UCL Clinical Psychopharmacology Unit, says: "Given that the Misuse of Drugs Act aims to signal to young people the harmfulness of drugs, this suggests a flaw with the current classification of drugs. We found that drug users rated legal substances such as alcohol and tobacco as more harmful than Class A substances like LSD and ecstasy. We found a high correlation between harm ratings by users and those made previously by scientific experts across all substances, suggesting users are well informed about the harms of drugs.

"The reported prevalence of use of each substance also suggests that the classification of drugs has little bearing on the choice of whether to use substances or not. For example ecstasy, a Class A substance, was the fourth most regularly used psychoactive drug, according to our survey.

"We also asked drug users about their perceived benefits of taking psychoactive substances, as this is clearly important in a person's decision of whether to take a drug or not. Psychoactive substances LSD, cannabis and ecstasy were consistently rated as having the highest short and long-term benefits. These findings add to the debate on the validity of the current classification of drugs in the UK.

"Worldwide, there are an estimated two billion alcohol users, 1.3 billion smokers and 185 million users of other drugs. Despite public health campaigns, levels of substance misuse continue to rise. One of the reasons for this may be the public's confusion about the actual risks of different drugs as they often receive conflicting messages from the legal system, the media and health campaigns. We recommend that future health campaigns consider whether to include the benefits of some drugs. By only citing harms, such campaigns likely represent – from a user's perspective – an unbalanced view and may mean that the overall message is more likely to be ignored."

The authors are following up the study with the launch of a new larger survey, in collaboration with the Beckley Foundation, hosted at www.internationaldrugsurvey.org.

Хм. О летальности смеси кокаин+перечный газ

Отличная статья на http://www.newscientist.com/article/mg20427345.300-cocaine-and-pepper-spray--a-lethal-mix.html?DCMP=OTC-rss&nsref=online-news:
DEATHS in US police custody during the early 1990s may have been the result of an interaction between capsaicin, the key ingredient in pepper sprays, and psychostimulant drugs, an experiment in mice suggests.

If the two have a fatal interaction in people then police forces might have to rethink their use of pepper spray as a non-lethal weapon, says John Mendelson of the Addiction and Pharmacology Research Laboratory at St Luke's Hospital in San Francisco, who led the mouse research.

In the early nineties, anecdotal reports emerged in the US of people dying after being sprayed by police. "They seemed to die very quickly," says Mendelson. At post-mortem, many of these people showed signs of having taken cocaine, so Mendelson wondered if capsaicin and cocaine could interact fatally in the body.

To investigate, his team injected cocaine, capsaicin or both at once into the abdomens of several groups of about 30 mice. Injections allowed them to control the dose of capsaicin the mice received, which wouldn't have been possible if the mice were simply sprayed, says Mendelson.

In one group of mice, cocaine was injected at a dose of 60 milligrams per kilogram of mouse weight, which killed just a few of them. But when the researchers injected a group with the same dose of cocaine plus capsaicin, the death toll was about half. "The presence of capsaicin in mice makes smaller amounts of cocaine more lethal," Mendelson says. When the team gave another group of mice capsaicin along with a higher dose of cocaine - enough to kill half of the mice on its own - the death toll rose to 90 per cent (Forensic Toxicology, DOI: 10.1007/s11419-009-0079-9). "We don't actually know how capsaicin reacts with cocaine to produce a lethal effect," admits Mendelson.

However, his team also reviewed 26 autopsy reports and Californian police reports between 1993 and 1995 of people who died shortly after being subdued with pepper spray. They noted that 19 of them had evidence of psychostimulants in their blood and nine had cocaine. Mendelson suspects that a fatal interaction takes place in the brain between capsaicin and psychostimulants.

Toxicologists are intrigued, but say further evidence is needed. "In real-life situations, humans inhale pepper spray, whereas these mice had the substance injected directly into their abdominal cavities," says Andy Smith of the Medical Research Council in Cambridge, UK. Kathryn Cunningham of the Department of Pharmacology and Toxicology at the University of Texas in Galveston says we don't know how much of the capsaicin that is sprayed in someone's face makes it into their bloodstream.

Peter Bibring, an attorney at the American Civil Liberties Union in Los Angeles, says the study adds weight to the ACLU's concern that pepper spray could be fatal. "Police departments need to make adjustments to minimise the chance it will be used on those under the influence of cocaine."

Norm Leong, a sergeant at the Sacramento Police Department in California says this could be a tough call: "It's impossible to know if someone is under the influence of cocaine, some other drug", has mental issues, or is just resisting arrest.

Конопля без каннабиноидов

До чего дошла наука... Читаем на http://www.biology-blog.com/blogs/permalinks/9-2009/drug-free-cannabis-plant.html
Drug-free Cannabis plant
In a first step toward engineering a drug-free Cannabis plant for hemp fiber and oil, University of Minnesota scientists have identified genes producing tetrahydrocannabinol (THC), the psychoactive substance in marijuana. Studying the genes could also lead to new and better drugs for pain, nausea and other conditions. The finding is reported in the recent issue of the Journal of Experimental Botany Main author is David Marks, a professor of plant biology in the College of Biological Sciences. The study revealed that the genes are active in tiny hairs covering the flowers of Cannabis plants. In marijuana, the hairs accumulate high amounts of THC, whereas in hemp the hairs have little. Hemp and marijuana are difficult to distinguish apart from differences in THC. With the genes identified, finding a way to silence themand thus produce a drug-free plant comes a step closer to reality. Another desirable step is to make drug-free plants visually recognizable. Since the hairs can be seen with a magnifying glass, this could be accomplished by engineering a hairless Cannabis plant. The scientists are currently using the methods of the latest study to identify genes that lead to hair growth in hopes of silencing them. "We are beginning to understand which genes control hair growth in other plants, and the resources created in our study will allow us to look for similar genes in Cannabis sativa," said Marks. "Cannabis genetics can contribute to better agriculture, medicine, and drug enforcement," said George Weiblen, an associate professor of plant biology and a co-author of the study. As with Dobermans and Dachshunds, marijuana and hemp are different breeds of the same species (Cannabis sativa), but marijuana contains much more THC than hemp, which is a source of industrial fiber and nutritious oil. Hemp was raised for its fiber which is similar to cotton but more durable in the United States until legislation outlawed all Cannabis plants because they contain THC. Today, marijuana contains as much as 25 percent THC, whereas hemp plants contain less than 0.3 percent. Hemp was once a popular crop in the upper Midwest because it tolerates a cool climate and marginal soils that won't support other crops but, after drug legislation, hemp fiber was replaced by plastic and other alternatives. Recent popular demand for hemp products has led some states to consider the economic and environmental benefits of hemp. North Dakota legislation aims to reintroduce it as a crop, and Minnesota is considering similar legislation. At the same time, California and other states permit the medicinal use of marijuana. "I can't think of a plant so regarded as a menace by some and a miracle by others," says Weiblen, who is one of the few scientists in the United States permitted to study Cannabis genetics. In 2006, Weiblen and his colleagues developed a DNA "fingerprinting" technique capable of distinguishing among Cannabis plants in criminal investigations. Posted by: Erica Source

Новое о курении марихуаны

Нашла на http://www.eurekalert.org/pub_releases/2009-08/acs-geo_1080509.php

In a finding that challenges the increasingly popular belief that smoking marijuana is less harmful to health than smoking tobacco, researchers in Canada are reporting that smoking marijuana, like smoking tobacco, has toxic effects on cells. Their study is scheduled for the Aug. 17 issue of ACS' Chemical Research in Toxicology, a monthly journal.

Rebecca Maertens and colleagues note that people often view marijuana as a "natural" product and less harmful than tobacco. As public attitudes toward marijuana change and legal restrictions ease in some countries, use of marijuana is increasing. Scientists know that marijuana smoke has adverse effects on the lungs. However, there is little knowledge about marijuana's potential to cause lung cancer due to the difficulty in identifying and studying people who have smoked only marijuana.

The new study begins to address that question by comparing marijuana smoke vs. tobacco smoke in terms of toxicity to cells and to DNA. Scientists exposed cultured animal cells and bacteria to condensed smoke samples from both marijuana and tobacco. There were distinct differences in the degree and type of toxicity elicited by marijuana and cigarette smoke. Marijuana smoke caused significantly more damage to cells and DNA than tobacco smoke, the researchers note. However, tobacco smoke caused chromosome damage while marijuana did not.

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ARTICLE #2 FOR IMMEDIATE RELEASE
"The Genotoxicity of Mainstream and Sidestream Marijuana and Tobacco Smoke Condensates"

DOWNLOAD FULL TEXT ARTICLE: http://pubs.acs.org/stoken/presspac/presspac/full/10.1021/tx9000286

Восстановление функций мозга после метамфетаминовой абстиненции

Интересно написано на http://www.biologynews.net/archives/2009/06/29/brain_functions_that_can_prevent_relapse_improve_after_a_year_of_methamphetamine_abstinence.html
Іn a study published online by the Journal of Substance Abuse Treatment, UC Davis researchers report that it takes at least a year for former methamphetamine users to regain impulse control. The results tell recovering substance abusers, their families and drug-treatment specialists that it can take an extended period of time for the brain functions critical to recovery to improve.

"Recovery from meth abuse does not happen overnight," said Ruth Salo, lead author of the study and a UC Davis assistant professor of psychiatry and behavioral sciences. "It may take a year — or even longer — for cognitive processes such as impulse control and attentional focus to improve. Treatment programs need to consider this when monitoring recovering addicts' progress during their early periods of abstinence."

Salo specializes in the behavioral, neuropsychiatric and cognitive outcomes of methamphetamine addiction — a particularly difficult condition to treat, primarily due to prolonged, intense cravings for the drug. During her career, she has worked with hundreds of methamphetamine addicts.

"All of them want to know if there is hope," Salo said. "We used to think most, if not all, effects of meth addiction were permanent. This study adds to the growing evidence that this assumption is not true. I can confidently tell patients that the longer they stay in a structured rehabilitation program and remain drug free, the more likely it is that they will recover some important brain functions."

For the current study, Salo used the widely-validated, computer-based Stroop attention test to measure the abilities of 65 recovering methamphetamine abusers to use cognitive control — or direct their attention to specific tasks while ignoring distractors. Study participants had been abstinent for a minimum of three weeks and a maximum of 10 years, and they had previously used the drug for periods ranging from 24 months to 28 years. The data for the 65 individuals were compared to Stroop attention test data from 33 participants who had never used methamphetamine.

"The test taps into something people do in everyday life: make choices in the face of conflicting impulses that can promote a strong but detrimental tendency," Salo explained. "For meth users, impairments in this decision-making ability might make them more likely to spend a paycheck on the immediate satisfaction of getting high rather than on the longer-term satisfaction gained by paying rent or buying groceries."

The study analyzed cognitive control in terms of the amount of time since methamphetamine was last used as well as total time spent using the drug. The researchers found that those who were recently abstinent (three weeks to six months) performed significantly worse on the Stroop test than those who had been abstinent one year or longer. In addition, there was no statistical difference between test results for those abstinent at least one year and non-drug using controls. Longer-term methamphetamine use was associated with worse test scores. Similarly, longer-term abstinence was connected to improved test performance.

According to Salo, the new study mirrors previous magnetic resonance imaging (MRI) studies she and her colleagues published in 2005 showing a partial normalization of chemicals in selected brain regions after one year of methamphetamine abstinence.

"Together, the studies provide strong evidence that, eventually, meth abusers in recovery may be able to make better decisions and regain the impulse control that was lost during their drug use period," she said.

Salo said that more research is needed to determine just how the brain recovers from methamphetamine addiction and if behavioral treatments can hasten that recovery. She plans to continue neuroimaging studies to further define the brain functions affected by the drug. Her ultimate goal is to provide information essential to refining treatment programs for this population of drug users.

"Meth use worldwide is pandemic," she said, referring to the estimated 35 million people who have used the neurotoxic stimulant or similar drugs. "Recovery is difficult, but possible. The point of my research is to better understand the neural and behavioral consequences of this toxic drug along with the brain and behavior changes that are possible with long-term abstinence."

Source : University of California - Davis - Health System