The Teen Brain on Weed

April 24, 2015

By Medical Discovery News

A brain

It is now legal to use marijuana (recreationally and/or medically) in more than 20 states and the District of Columbia, and as more places debate legalizing the substance, more people are asking about its consequences on human health. There are many myths and misconceptions out there, but this is what science has to say about the subject.

As with all substances, the health effects depend on the potency, amount, and a person’s age. An independent scientific committee in the United Kingdom evaluated how harmful various drugs were based on 16 criteria and ranked heroin, crack cocaine, and methamphetamine as the most harmful drugs to individuals using them, and ranked alcohol, heroin, and crack cocaine as the drugs that cause the most harm to others. Marijuana ranks eighth, with slightly more than one-quarter the harm of alcohol.

Short-term use is associated with impaired short-term memory, making it difficult to learn and retain information while under the influence. Short-term use can also impair motor coordination, interfering with tasks such as driving. The overall risk of an accident doubles if a person drives soon after using marijuana. In comparison, those with blood alcohol levels above the legal limit are five times more likely to have an accident, and the combination of alcohol and marijuana is higher than either one alone.

Long-term or heavy use is associated with diminished life satisfaction and achievement overall. At high doses, marijuana can cause paranoia and psychosis, and long-term marijuana use increases the risk of developing schizophrenia or other chronic psychotic illnesses. Nine percent of all marijuana users, or 2.7 million people, develop an addiction to it. That figure jumps to 25-50 percent for those who use marijuana daily, and 17 percent of people who begin using marijuana as adolescents become addicted. Cannabis withdrawal syndrome is real and includes symptoms of irritability, sleep disturbance, dysphoria, craving, and anxiety.

Adults who occasionally use marijuana do so with little to no risk, but adolescent brains are not fully developed, making them more vulnerable to the adverse effects of marijuana. Using marijuana during adolescence can alter brain development, causing impaired cognition and lower IQs. This is probably because the active ingredient in marijuana, tetrahydrocannabinol, affects the brain’s ability to make connections between neurons in certain regions of the brain. Adolescent marijuana users also have a smaller hippocampus, which is important in learning and memory, and a less active prefrontal cortex, which is important in cognitive tasks such as planning and problem-solving.

Since acute marijuana intoxication can impair cognitive functions for days, students who use marijuana may function well below their natural abilities, causing academic difficulties. High school dropouts do report higher marijuana usage than their peers. Some evidence suggests that these cognitive impairments could be long-lasting or permanent in long-term users who started at younger ages, which can impact their abilities to succeed academically and professionally.

There is no clear association between long-term marijuana use and any deadly disease, although chronic marijuana smokers have increased rates of respiratory infections and pneumonia and an increased risk of heart attack and stroke. The effects of marijuana on a developing embryo and the effects of second-hand or third-hand marijuana smoke have not been well-studied, but as marijuana legalization continues to be an issue the science behind it will as well.

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Beer: It’s the Yeast that Counts

March 13, 2015

By Medical Discovery News

Beer - It's the Yeast That Counts

Humans have been drinking fermented beverages such as beer for thousands of years. Long before microbrews were invented, men relied on wild yeast to produce their ale. But we aren’t the only ones who found something so appealing in yeast – fruit flies do as well.

A beer’s aroma and flavor are due to it ingredients, which usually include malted grains, commonly barley and wheat, then hops for bitterness. However, a key determinant of a beer’s flavor is the yeast. During fermentation, yeast introduces a variety of aromatic molecules called acetate esters. The question of why yeast produces these aromatic compounds has been a mystery, until now.

Fifteen years ago, a scientist in Belgium named Kevin Verstrepen rushed out of the lab to get to a bar one Friday evening, leaving three flasks of yeast sitting open on his lab bench. Upon returning on Monday, he discovered that fruit flies from a neighboring genetics lab had invaded his own. Fifty flies were floating in the flask of yeast that had been engineered to make 100 times more of the aromatic molecules that a standard strain. Two flies were in the flask of normal yeast, and none were in the flask of yeast that did not produce those aromatic molecules. He deduced that yeast produces aromatic molecules with aromas similar to ripening fruit to attract flies, but wondered why.

Years later, Verstrepen teamed up with other scientists to repeat the experiment, and once again the amount of aromatic molecules produced by a strain of yeast correlated with the number of flies attracted to it. To be sure the aroma was responsible for attracting the flies, they synthesized the aromatic molecules and added them to a flask of yeast that did not produce them. Sure enough, the flies returned. They then used flies whose brains had been modified to express a fluorescent protein, which would light up when there was neural activity. They discovered that a compound called isoamyl nitrate, which has a smell similar to overripe bananas, causes intense brain activity in flies. Fruit flies apparently can use such aromatic molecules to find yeast, an important part of their diet.

They then wondered whether the yeast that attract flies have an advantage by spreading further into their environment. Using normal yeast and scentless yeast that had been colored differently showed that the aromatic yeast spread four times more into the environment. Basically, yeast emit signals in the form of molecules that flies are attracted to as a food source, but the yeast benefits by being spread by the flies. Yeasts do not have any means of propulsion, so hitching a ride to a new food source on the tiny hairs of a fruit fly’s legs solves their travel problems.

While not reported in a scientific publication, they collected fruit flies from their homes, crushed them up, and analyzed them for yeast. Sure enough, the flies harbored yeast that produced the aromatic compounds. For the final experiment, Verstrepen cultured the yeast and guess what he did with them?  Made beer, of course.  It was reportedly delicious.

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Dark Secrets of Medicine Shows

Aug. 23, 2013

By Medical Discovery Shows

It’s hard to believe that people used to drink snake oil as a “universal remedy,” or rely on a patent medicine called Mugwumps to prevent sexually transmitted diseases.

Yet, from colonial times to the 1900s, people would unquestionably turn to such “cures.” Patent medicines were sold directly to a patient from the manufacturer without a prescription through mail order, in shops, and in traveling medicine shows. They were trademarked (which is not the same as today’s patenting) by the seller yet untested and unregulated, and as such, rarely worked as advertised. Eventually, people even used the term snake oil salesman as a synonym for a fraudster.

Among the early patent medicines to arrive in America were Daffy’s Elixir Salutis for “colic and griping,” Dr. Bateman’s Pectoral Drops and John Hooper’s Female Pills. These and many other remedies were available for just about any ailment and often made outlandish claims of their effectiveness. An interesting study revisited these patent medicines to discover just what they contained and if they could have lived up to the hype.

At a meeting of the American Chemical Society, the research team headed by Dr. Mark Benvenuto presented their examination of patent medicines from the Henry Ford Museum in Dearborn, Mich. They tested 50 of the hundreds of such medicines in the museum’s Health Aids collection.

Patent medicines were produced long before the advent of the Food and Drug Administration’s regulations and testing standards. Many patent medicines were based on vegetable extracts along with abundant amounts of alcohol. Others contained dangerous substances such as opium, cocaine, heroin, mercury, silver, arsenic, or even the radioactive element thorium. Sadly, some of these potent concoctions were used to treat babies for colic or fussiness, sometimes with tragic results. 

But some were found to contain some substances that could actually be healthy. For example, Dr. F.G. Johnson’s French Female pills contained iron, calcium, and zinc, all of which are common supplements taken by people today. However, these pills also contained potentially toxic lead.

The patent medicine industry flourished during the Industrial Revolution due to the progress of manufacturing, advertisements in newspapers and magazines, and a general distrust of conventional medical care at the time. That started to change when journalist Samuel Hopkins Adams wrote a series of articles for Collier’s Weekly in 1905 entitled “The Great American Fraud,” exposing the industry’s fraudulent and deceitful practices and unsafe manufacturing processes. In 1906, with the strong support of then President Teddy Roosevelt, Congress passed the Pure Food and Drug Act. Drug laws have continued to evolve and in 2002, over-the-counter medications were required to print a “Drug Facts” label. 

While traveling medicine shows have disappeared, advertisements for herbal supplements with improbable claims for rapid weight loss and sexual enhancement litter magazines and TVs. Just as they do now, scientists 100 years in the future will probably wonder what we were thinking!

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