Medicine and Me

Hello everyone! We're three British medical students from the UK, who somehow managed to survive the arduous process of getting into medical school. One of us goes to King's College London, another to UCL, and the third person to Seoul National University. If you have any questions about applying to med school/what medical is like/about those universities in particular, feel free to ask! We have our own private Tumblrs as well: http://jaunebanane.tumblr.com/ http://jiti.tumblr.com/ http://spicyveggieburger.tumblr.com/ Enjoy!

[medicineblogs]

Update

We have somehow managed to acquire several followers today, so thought it would be a good idea to reintroduce ourselves! We’re three first-year medical students, studying at KCL, UCL and Seoul National University. If you have any questions about applying to medical school, the course, those universities in particular, or medical school in general, feel free to ask us.  

Thanks for following us! 

- people that should be revising right now instead of wasting time on Tumblr 

[themedicalstate]

Brain Scans Can Predict Which Alcoholics Are Most Likely to Relapse

For any addiction, external cues and stress can trigger cravings that are hard to resist, and the latest research points to an area of the brain that might be responsible for sabotaging recovery.

The study, which was published in JAMA Psychiatry, found that those with elevated activity in a region called the ventromedial prefrontal cortex (vmPFC) even while they were at rest were eight times more likely to drink again within 90 days than those whose vmPFC was calmer when they were feeling relaxed.

The findings are “a major contribution,” to understanding alcohol addiction, said Dr. Nora Volkow, director of the National Institute on Drug Abuse, in a co-written editorial that accompanied the research.

The authors, led by Rajita Sinha, professor of psychiatry at Yale University, studied the brain activity of 45 recovering alcoholics who were in a treatment program based on the 12 steps of Alcoholics Anonymous, during three different experiences — a stressful one, one that enticed them to drink, and a neutral, relaxing situation. The scientists compared their brain activity patterns to those of 30 social drinkers of similar age, intelligence and gender. The participants in the rehabilitation program were abstinent for four to eight weeks.

In order to generate the three experiences, the researchers asked all of the participants to describe recent stressful events, situations in which they ended up drinking, and circumstances that helped them to feel relaxed (such as sitting on a beach and listening to the waves). These were compiled into personalized two-minute videos that the team played back to the volunteers while they were brains were scanned using functional MRI. The scenarios induced the desired emotional states; heart rates rose during the stressful experiences and fell during the more relaxing ones.

But while the alcoholics appeared to be relaxed while picturing themselves on sunlit beaches, their brains — specifically the vmPFC — told a different story. “With relaxation, social drinkers relax their prefrontal cortex. It’s deactivation,” says Sinha, “For the alcoholic brain, what we found in this region was hyperactivity, as if it were stuck and primed and ready to go.” The alcoholics also showed elevated activity in an area linked with craving reward and pleasure even while they were relaxed.

Under stress, these regions also looked very different in the two groups. “[The stress response in] social drinkers goes up and responds as [it] needs to do when faced with a challenge: you want the system regulated to get ready for stress and to calm down afterwards. In the alcoholic brain, that [response] was flat or blunted,” Sinha says.

The discrepancy suggests that a more sensitive or active vmPFC could be making alcoholics vulnerable to drinking cues or to seeking out the satisfaction that comes from alcohol – a set-up for relapse. “The most important finding is the identification of a functional disruption in the brain that predicts who is most at risk for relapse,” Sinha says.

The vmPFC and the reward circuit are key nodes in the neural network that guides decision-making. These regions help to add value to experiences, allowing the brain to determine whether they will be helpful or harmful, punishing or pleasant.  “[Activity in these areas is] important in predicting what’s important and what’s not,” says Sinha, explaining that stimulating these circuits alerts other regions in the brain about how to respond once values are set. In the case of addictions, the heightened activity in these areas may bias the system to see the drugs or alcohol as more important than anything else.

“If it’s not working, and petered out like we’re showing [in the alcoholics], then other areas of brain like [those that control your] automatic response under stress are likely to override everything else,” she adds.  For alcoholics, not surprisingly, this automatic response would be to drink to satisfy cravings and respond to stress.

The findings may dovetail with the results from another study, published in the same issue of JAMA Psychiatry, that explored another key factor in alcoholic drinking: counteracting unpleasant moods.

Among more than 40,000 adults participating in the National Survey on Alcohol and Related Conditions, the researchers found that those who drank to lift their spirits tripled their risk of alcoholism, as well as prolonging the disorder.  The study estimated that nearly one-third of persistent alcoholism is linked to such self-medication, as well as 12% of new cases.

Both studies suggest potentially more sophisticated ways of addressing alcoholism by focusing on the stress and cues that can drive excessive drinking. In Sinha’s research, for example, the relapse rate overall was 71%— and it was even higher in those with over-activity in the vmPFC during relaxation. New approaches, such as mindfulness meditation, which could potentially calm the hyperactive alcoholic brain, might be more effective than programs that focus solely on changing behavior. Sinha is also studying a medication called Prazocin, which could affect the activity of the vmPFC. With better prediction of who is most likely to relapse, she says, could come better prevention strategies that are better tailored to what is driving alcoholics to drink again.

[thisblogdeadyeet]

A White Blood Cell chasing and consuming a Bacterial Organism through a process called Phagocytosis.

[sagansense]

Scientists Implant Monkeys’ Cells Back Into Their Own Brains The research is a step along the way to personalized stem cell therapies.

A Neuron This is a photo of neuron created from a stem cell, but it is not one of the cells that was implanted in the monkeys in the study below. Courtesy Yan Liu and Su-Chun Zhang, Waisman Center, University of Wisconsin–Madison

Scientists have taken cells from rhesus monkeys’ skin, turned them into neural cells, then implanted them successfully into the monkeys’ brains. After six months, the transplanted cells showed no scarring and looked healthy and normal—except that they glowed green, a characteristic the scientists added to the cells so they could find the cells later.

The feat is a basic step toward personalized stem cell therapies, in which people might get treated for diseases using their own healthy cells. Of course, a study in monkeys—and one that didn’t cure any disease—is a long way from something your doctor could order. But that’s the eventual aim of studies like this.

The research team, from the University of Wisconsin in Madison, first took skin samples from three rhesus monkeys. They used the famed Yamanaka cocktail to transform those skin cells into pluripotent stem cells, a kind of “blank slate” cell that’s able to develop into any type of cell in the body. It was just the kind of experiment that Popular Science predicted would take off in 2013.

After making stem cells from skin cells, the Wisconsin team coaxed the stem cells into becoming something completely different: early-stage neural cells. At this point, the researchers implanted the cells back into the monkeys, in which they had artificially induced a Parkinson’s-like disorder.

Once inside the monkey brains, the neural cells finished their maturation, got great jobs and their own apartments… I mean, they turned into specialized brain cells called neurons, astrocytes and oligodendrocytes. They didn’t die, get rejected by the monkeys’ brains as foreign, or appear cancerous, all of which have happened in some previous stem cell implant studies.

Although the new brain cells settled well into the monkeys’ brains, there weren’t enough of them to improve the monkeys’ Parkinson’s symptoms. The researchers will still have to see if they can implant cells that actually help with symptoms. And they’ll need to keep checking on the monkeys’ brains in the months and years to come, to make sure the implants don’t cause problems later on.

The Wisconsin team published their work today in the journal Cell Reports.

[University of Wisconsin-Madison]

[medicalschool]

Illustration of the Human Heart

[kny111]

How The Brain Turns Reality Into Dreams

Dreams make perfect sense when you’re having them. Yet, they leave you befuddled the next morning, wondering “where did that come from?” The answer may lie in the dreams of people with amnesia, researchers report in an issue of Science.

Much of the fodder for our dreams comes from recent experiences. For this reason, scientists have tentatively supposed that the dreaming brain draws from its “declarative memory” system, which includes newly learned information.

The declarative memory stores information that you can “declare” you know, such as the square root of nine, or the name of your dog. Often, you can even remember when or where you learned something - for example, the day you discovered the harsh truth about Santa Claus. That’s called episodic memory.

People who permanently suffer from amnesia can’t add new declarative or episodic memories. The parts of their brains involved in storing this type of information, primarily a region called the hippocampus, have been damaged. Although amnesiacs can retain new information temporarily, they generally forget it a few minutes later.

If our dreams come from declarative memories, people with amnesia shouldn’t dream at all, or at least dream differently than others do. But new research directed by Robert Stickgold of Harvard Medical School suggests quite the opposite. Just like people with normal memory, amnesiacs replay recent experiences when they fall asleep, Stickgold’s study shows. The only difference seems to be that the amnesiacs don’t recognize what they’re dreaming about.

Dreaming of Tetris

Every day, the people in the study played several hours of the computer game Tetris, which requires directing falling blocks into the correct positions as they reach the bottom of the screen. At night, the amnesiacs didn’t remember playing the game. But, they did describe seeing falling, rotating blocks while they were falling asleep.

A second group of players with normal memories reported seeing the same images. Therefore, Stickgold’s research team concluded, dreams must come from the types of memory amnesiacs do have, which are called “implicit memories.” These are memories that scientists can measure even when individuals don’t know that they have them.

One class of implicit memories is found in the procedural memory system, which stores information that you use without really being able to say how you know what you’re doing. When you ride a bicycle for the first time in years, or type on a keyboard without looking, you’re relying on procedural memory.

Another type of implicit memory uses “semantic” knowledge, and resides in different parts of the brain, including a region called the neocortex. Semantic knowledge involves general, abstract concepts. Both groups of Tetris players, for example, only described seeing blocks, falling and rotating, and evidently did not see a desk, room, or computer screen, or feel their fingers on the keyboard.

Without help from the hippocampus, new semantic memories are too weak to be intentionally recalled. But they can still affect your behavior - for example, causing you to buy a certain brand of something you saw in an advertisement you don’t remember.

In contrast, the information in episodic memories is associated with specific times, places or events. Without these “anchors” to reality, it’s no wonder that dreams are so illogical and full of discontinuity, the study’s authors say.

Stickgold believes that dreams serve a purpose for the brain, allowing it to make necessary emotional connections among new pieces of information. “Dreams let you consolidate and integrate your experiences, without conflict with other input from real life,” Stickgold said. “Dreaming is like saying, ‘I’m going home, disconnecting the phone, nobody talk to me. I have to do work.’”

Because the hippocampus seems to be inaccessible for this “off-line” memory processing, the brain may use the abstract information in the neocortex instead. According to Stickgold’s theory, dreaming is like choosing an outfit by reaching into bins labeled “shirts,” “pants” and so on. You’ll rummage up something to wear, but it won’t be a perfectly matching ensemble.

Full Article..

© 2012 American Association for the Advancement of Science

Click here for more information on Dreams

[courtneyannestewart]

Surgeon :: Illustration

[medicineblogs]

"The good physician treats the disease; the great physician treats the patient who has the disease." William Osler

[medicalschool]

Sliced section of human head

Mütter Museum of the College of Physicians of Philadelphia

[aspiringdoctors-blog]

I SAW THIS WHEN I WAS THERE IN JUNE.

Megacool.

[throughascientificlens]

Male Contraceptive Pill On The Horizon?

A completely reversible male contraceptive may enter the market some time soon as researchers take another step towards developing a male contraceptive pill.

Findings: the pill rendered lab mice completely infertile, as sperm production was down and the sperm produced were significantly less mobile. Not only this but the process is reversible: as soon as the drug is no longer administered; sperm production reverts to normal.

The new drug does not affect the hormone system, nor does it effect the sex drive. There were no apparent side effects in the mice. The drug was originally intended as a cancer treatment, but rather it was found that the drug inhibits the testes ability to produce mature sperm.

It is expected that it will take some time for the product to reach the shelves as the drug has to be developed further and refined, and then tested again and again. They expect it to could take up to a decade. However long it takes, this is a great step forward because there hasn’t been a reversible form of male contraception since the invention of the condom. (x)

[laboratoryequipment-blog]

Parasite May Cause Suicide Attempts A parasite thought to be harmless and found in many people may actually be causing subtle changes in the brain, leading to suicide attempts. New research appearing in the Journal of Clinical Psychiatry adds to the growing work linking an infection caused by the Toxoplasma gondii parasite to suicide attempts. Michigan State Univ.’s Lena Brundin was one of the lead researchers on the team. About 10-20 percent of people in the United States have Toxoplasma gondii, or T. gondii, in their bodies, but in most it was thought to lie dormant, says Brundin, an associate professor of experimental psychiatry in MSU’s College of Human Medicine. In fact, it appears the parasite can cause inflammation over time, which produces harmful metabolites that can damage brain cells. Read more: http://www.laboratoryequipment.com/news/2012/08/parasite-may-cause-suicide-attempts

[neurosciencestuff]

A robot that can reproduce the dexterity of the human hand remains a dream of the bioengineering profession. One new approach to achieving this goal avoids trying to replicate the intricacy of the bones, joints and ligaments that produce our most basic gestures.

A Sandia National Laboratories research team has adopted just such a strategy by designing a modular, plastic proto-hand whose electronics system is largely made from parts found in cell phones. The Sandia Hand can still perform with a high level of finesse for a robot, and is even capable of replacing the batteries in a small flashlight. It is expected to cost about $10,000, a fraction of the $250,000 price tag for a state-of-the-art robot hand today.

[sutured-infection]

Dicephalus dibrachius diauchenos, from Barton Cooke Hirst’s Human Monstrosities: Volume 4, 1891

[sciencesoup]

The science behind hearing loss

The cochlea in our inner ear contains 15,000 tiny, hair-like structures called “stereocilia”, or hair cells. There are two types: auditory and vestibular, responsible for hearing and balance respectively. Auditory hair cells function by bending in response to sound, and their movements are transmitted as electrical signals to the brain, which interprets them as sound. When these hair cells are damaged or killed, it can cause permanent hearing loss—and although hearing aids can be used as a kind of “hearing band-aid”, the cells cannot be regenerated. Birds and many amphibians have the natural ability to recover their hearing by regenerating hair cells, and researchers are currently studying them in hopes of artificially mimicking their regeneration process. They have also recently found that the zebrafish uses hair cells on its body to sense its surroundings, and these work in similar ways to humans’, presenting an opportunity for experimentation to screen helpful chemicals and treatments. Researchers have managed to identify protective chemicals by dyeing the fish’s hair cells, administering the chemicals, then exposing the fish to another chemical known to kill hair cells. The surviving hairs remain dyed, signifying that the protective chemical worked. These chemicals are now being tested on rodents, but there’s been no human testing yet, and it’s estimated that a cure for hearing loss is still 20 years away.

Read more about the research of zebrafish

[joshbyard]

Russian Scientists Successfully Transplant a Synthetic Larynx

The latest graft is different, because it involves a synthetic structure rather than a graft from a cadaver.

Before implantation, the part was seeded with stem cells from the patient’s own bone marrow, so that once transplanted it would grow its own layers of native surface cells. The coating was performed in a special reactor by Harvard Bioscience, a company in Holliston, Massachusetts.

“We see this as the beginning of growing synthetic organs,” says the company’s president, David Green. “It’s the stuff of scientific fiction becoming medical reality.” Last year, a man received the first synthetic windpipe, a Y-shaped appendage that was also covered with the patient’s own stem cells.

(via First synthetic larynx part transplanted - health - 27 June 2012 - New Scientist)

[nurse-on-duty]

[jaunebanane-blog]

[medicalstate]

Gastric Subway by Steven McGaughey.

In the past, I have made no secret of my interest of the world of transportation. Steven, a medical student who has a passion for both medicine and design, produced this conceptualized diagram of the gastric area, the tissues, and vessels.

For more works by this exceptional student, you can check out some of his illustrations on his blog or website.