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Healing a “Broken” Heart March 4, 2011

Posted by Kyle in Biology, Chemistry, Health, Medicine, Physiology.
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Irreparable Harm

The majority of those reading this have probably experienced some sort of injury in their lifetime.  Injuries such as cuts and broken bones will soon heal with proper care, but there are certain tissues that if damaged, cannot repair themselves. Heart tissue and brain tissue are two examples that come to mind. This may be the case for most of us adult humans, but new research out of The University of Texas Southwestern Medical Center at Dallas is pointing out that some newborn mammals have the ability to heal completely when it comes to heart damage. The only problem is, at some point along the line, as we age, the heart loses this ability to heal itself. Still, this is a very important discovery for a society that suffers greatly from heart disease, which kills thousands of Americans every year.

Studying a Broken Heart

Researchers found that in newborn mice, when sections of heart were removed, the heart had completely healed within three weeks. The hearts then functioned as normal with no signs of damage. Understanding how this works and why the heart stops doing it after a certain amount of time is now the next step for researchers. Unlike when you tear a hamstring, damage to cardiac tissue after a heart attack doesn’t just heal with time. So for those who suffer from heart problems, a discovery like this brings them one step closer to a healthy heart in the future.

Of Mice & Men

Obviously mice, which help us a lot more than most people realize, and humans are a little different from each other, but seeing results like this in another mammal is still promising. If nothing else, it is definitely a huge step in the right direction for researchers looking to cut down on the number of heart related deaths. For now though, it is important for people to remember that they only have one heart, and taking care of it should be a priority.


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Mysterious Melatonin December 18, 2010

Posted by Kyle in Biology, Chemistry, Health, Medicine, Neuroscience, Nutrition, Physiology.
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I am sure everyone has already heard of a little compound known as melatonin. Melatonin is a hormone that can be found in many different organisms including plants, although most people know melatonin for its actions in mammals. In humans, melatonin is produced in the brain by the pineal gland. Circulating melatonin levels have been found to be high at night and low during the day, which is consistent with research that has shown that light suppresses melatonin. Because melatonin plays a role in controlling the circadian rhythm, it has received much interest for its use as a treatment for various sleep disorders. Because melatonin is a hormone, supplementing melatonin can present some issues.

Many people have used melatonin supplements to help them sleep at night. If you take a trip to your local drug store you are likely to find melatonin on the shelf. The first time I came across melatonin supplements I couldn’t help but think about the potential negative aspects to selling melatonin over the counter, unregulated. As many of you know, the human body likes to maintain homeostasis. When this delicate balance is interrupted, the body will react to return to homeostasis. I started to wonder what happens when someone takes melatonin supplements. The first thing that comes to mind is a decrease in the amount of melatonin receptors or a decrease in the production of melatonin itself, or both. I also wondered about possible side effects of increasing melatonin levels. As we have seen with many other hormones, multiple pathways and mechanisms can be influenced by a single hormone. So someone taking melatonin to help them sleep could inadvertently throw off other pathways, like those involved in reproduction for example.

Melatonin has been shown protect against reactive oxygen species, which can wreak havoc inside cells. This could potentially be an obvious benefit to taking melatonin supplements, especially if it helps an individual sleep at night. While sifting through the literature, I was unable to find any studies specifically looking at the negative effects of taking melatonin supplements, if any. But just because it isn’t proven that something is bad, doesn’t mean the potential for bad isn’t there. Also, other countries have taken action to stop over the counter sale of melatonin. Of course, there is also the question, do melatonin supplements even work?  How much of the melatonin present in a melatonin pill is denatured by stomach acids or excreted in urine before it even has an effect?

I am skeptical of melatonin supplements, if you haven’t noticed yet. To each his own, but I don’t think I will be purchasing or taking any melatonin supplements in the near future.  Good luck to everyone on their upcoming finals. Make sure to get plenty of sleep, although if your to-do list looks like mine, that won’t be happening.

The Science of Satiation October 16, 2010

Posted by Kyle in Behavior, Biology, Chemistry, Health, Nutrition, Uncategorized.
3 comments

Slow down or you’ll get a stomach ache!

My parents always told me that if I eat my food really fast, I may feel sick later. I am sure most people have experienced this at least once in their life. It seems that the reason for this is…that the faster you eat, the faster your stomach fills up. Your stomach ends up being full, or over-filled, before your body realizes it. By the time you do feel full, it is too late to stop eating and your stomach may feel like it’s going to explode.

It’s bad enough that your favorite meal can cause you pain after you devour it, but that’s not all it will do. Common sense should tell you that eating too much of something can potentially lead to being overweight. So if you’re eating too fast you can end up doing just that, gaining a lot of weight. An article from the British Medical Journal points out that eating too fast triples the risk of being overweight. Makes perfect sense…more food in equals more pounds put on.  But  the next question remains: what are the mechanisms behind all of this?

The science of satiation

An article out of The Endocrine Society’s Journal of Clinical Endocrinology & Metabolism (JCEM) points out that gut hormones my play a part in why people who eat fast end up overeating. As Alexander Kokkinos, MD, PhD, of Laiko General Hospital in Athens, Greece points out, gut hormones that signal the brain to stop eating may be impacted by the rate of eating.  The hormones that Kokkinos article examined were peptide YY (PYY) and glucagon-like peptide (GLP-1) which work to signal to us that we are full after a meal. For the study, the researchers took blood samples from participants after they had all eaten the same meal, however, the amount of time each participant took to eat the meal varied.  Their results showed that the participants who took longer periods of time to eat the meal had higher levels of the gut hormones and felt more full than those who ate their meals faster. So what does this all mean?

Fast food

Your body tries its best to tell you stop eating, but if you don’t get the signal in time it doesn’t matter.  As many Americans go about their day, they consume a massive amount of calories for very little cost. Going through the drive through doesn’t burn nearly as many calories as chasing down a woolly mammoth. Our early ancestors couldn’t go through the drive through for dinner, they had to work for their meal. Not only that, they probably didn’t eat nearly as much as we do today.  Consuming a ton of calories and burning very few  makes someone more likely to be overweight, but if you add in the fact that some people are consuming their meals in only a few minutes and eating large portions, these people are at a much higher risk of gaining weight. So next time you sit down for a meal, try and eat slowly. This will give your gut time to tell your brain that it’s time to quit eating.  Your gut will be happy, and you may just lose a few pounds in the long run.

Penguins, endangered? May 3, 2010

Posted by Kyle in Behavior, Biology, Climate Change, Ecology, Environment/Conservation, Evolution, Fun.
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"I believe I can fly!"

Cape penguins (Spheniscus demersusare) are an endangered species of penguins off the coast of South Africa. Between 2001 and 2009 there was a 60% decline in population numbers of Cape penguins. Researchers believe that the decline in Cape penguins is partly due to the lack of food as a result of overfishing.  Without food, the penguins obviously can’t survive.  A study done by researchers in South Africa has shown that by managing commercial fishing, they may be able to restore population numbers in penguins.

After doing a little more research, I discovered an easier solution to the problem. The penguins could just fly away (similar to polar bears rapidly evolving), and using a strategy similar to what was done in the movie Fly Away Home, the penguins could be saved. While it may seem slightly unrealistic, just watch the video below and all doubt will be removed. It seems that penguins learning to fly isn’t that crazy of an idea. (The video is obviously not real, and I am not serious.)

The “CSI-effect” May 3, 2010

Posted by Kyle in Genetics, Science & Culture.
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I recently found an interesting news article addressing an issue stemming from some popular television shows. As you have probably noticed, it is almost impossible to flip through the channels and not find at least one cop drama. While these shows may be interesting, some people are apparently having trouble separating reality from television.  According to the Marion County Crime Lab, there has been a dramatic increase in the demand for DNA evidence in criminal cases. This has been referred to as the “CSI-effect.” While this is not necessarily a bad thing, it has created an increased work load for the crime lab technicians, by roughly fifty percent.

"CSI-effect" based on the popularized TV series

Unlike the shows on T.V., there isn’t always DNA found at a crime scene. Also, it just simply isn’t possible to test every square inch of every crime scene. This has created issues in criminal cases when jurors want DNA evidence, but there isn’t any. When jurors confuse reality and television, they can begin to have unrealistic expectations of investigators. However, the positive side is the increased work load for the crime lab has led to the identification of many suspects, who may have never been identified otherwise.

DNA testing of firearm

A more recent article reported that prisons will begin to use DNA testing to determine the owners of items such as weapons and cell phones confiscated. Officials hope that this new tool will help cut down on the amount of contraband in Indiana prisons. An Indianapolis based company, Forensic ID,  has been contracted to run the program. With the advancement of science and technology many things are now possible that sound like they are from a science fiction movie. It is hard to imagine what will be possible in a few hundred years from now.

Lazy Birds May 3, 2010

Posted by Kyle in Behavior, Biology, Ecology, Evolution.
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Being a bird can be extremely difficult, especially when it comes to raising offspring.  The best way to pass on your genes, and at the same time spend no energy in doing so, is to let another bird do the work!

Brood Parasites

brood parasite young outcompete their host "siblings"

Brood parasites get around the huge investment of raising offspring by tricking another bird into doing it.  Brood parasitism is not a very common reproductive strategy across species (although rates of brood parasitism are high), but it definitely has its benefits.  The less time a bird is spending incubating eggs, the more time that individual can spend on foraging or mating.  The handful of species that use this strategy to gain an edge are constantly trying to trick the host birds, while the host birds are always on the lookout for parasitic eggs. This has led to an evolutionary arms race, with both sides working hard to win.

The costs of being fooled by brood parasites are huge. Not only does the fooled bird have to spend time raising someone else’s offspring, usually it’s not even the same species of offspring.  There is no genetic benefit in raising someone else’s young.  There is also the possibility that the parasitic chick out-competes the host’s chicks. This is the case with the Cuckoo Finch (Anomalospiza imberbis) and the Tawny-flanked Prinia (Prinia subflava). If the Cuckoo Finch egg is not discovered by the host, the Cuckoo Finch chick will hatch first and grow larger than the host’s chicks, out-competing its “siblings” for food and space until the host’s chicks eventually die. The cost associated with this relationship has led to a complicated defense system used by Prinias.

egg patterns of host and parasite are very similar

In a study done by Dr Claire Spottiswoode and Dr Martin Stevens of the University of Cambridge, the researchers worked on the two tropical African species to determine what strategies are used by both sides to win the battle. The back and forth struggle between the two species has resulted in Cuckoo eggs being almost identical to those of the Prinia. Researchers tested how Prinias detect impostures by taking eggs from Prinia nests and putting them in other Prinia nests. They then observed whether or not the eggs were rejected.  The results showed that the Prinia are extremely talented when it comes to distinguishing between their own eggs and those of another bird. By using color and pattern the host birds are able to distinguish among their eggs and those of the parasite birds. Although this sounds like a great plan, the reason it isn’t so popular is because it doesn’t really work that well. In another study researchers used Zebra Finches (Taeniopygia guttata) to look at brood parasitism, and found that only one-third of the eggs laid by brood parasites are actually reared.

Bees could be in trouble May 2, 2010

Posted by Kyle in Biology, Environment/Conservation, Policy.
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honey bee pollination

To many people bees of the family Apidae (including honey bees, Apis mellifera and bumblebees, genus Bombus) may seem like an annoying insect, but to flowers and other plants they are vital. Bees pollinate many crops that we rely on as a food source.  For this reason, bees are essential. Bees are obviously important in the wild, but they are also used commercially in greenhouses.  Scientists have noticed, however, that these important creatures have been on the decline. This could potentially be devastating to the crops that rely on bees for pollination as well as populations that rely on those crops for food.

Researchers Michael Otterstatter and James Thomson of the University of Toronto believe that the decline in bee populations could be a result of a pathogen spreading from commercial populations to wild ones. Commercial bees are often infected with the pathogen Crithidia bombi. To test this hypothesis, researchers tested populations near greenhouses as well as populations not near greenhouses to determine the percentage of infected individuals. As was expected, wild populations of bees closer to greenhouses had higher infection rates than those that were not near greenhouses. This points to commercial populations of bees as the source of the infection. As the commercial bees escape and mingle with wild bees, they are spreading the pathogen that is causing declining bee numbers.

While this problem may not be so bad now, over time there could be serious consequences. The declining bee numbers could have a negative impact on crops, potentially leading to a shortage in the food supply. As researchers in Europe have discovered, a decline in bee diversity is also making it harder for wild bee populations to survive. As a result, bees have not only started to disappear, but plants have as well. A study found that in 80 percent of bee populations biodiversity had declined.  As biodiversity declines, so do the chances that populations would survive widespread infection. At least in this study, it is unclear what is causing the declines in both bees and plants, or if they are related. These two studies highlight the importance of regulating commercial operations where biodiversity can be influenced. By better managing the diseases found in commercial bees as well as species overlap with wild populations, the issue could be curtailed.

A few examples of the pros and cons of exercise May 2, 2010

Posted by Kyle in Uncategorized.
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If finals have you stressed out and feeling down, maybe you should try a little “green exercise.” According to Jules Pretty and Jo Barton, green exercise is any physical activity done in nature. In their study, the results show that just a small amount of time outdoors is a plus for mental health and sense of well being. Something as simple as taking a walk in the Eco Lab could boost your confidence after a few long hours of studying.  The best part is the evidence shows that optimum benefits are achieved after just five minutes of activity. So whether you like to run, walk, or ride, you don’t have to spend much time doing it to feel better. This is great news for people who don’t really have a lot of spare time, like a student studying for finals. The study included over 1,200 individuals, and the activities they participated in included walking, gardening, cycling, fishing, boating, horse-riding and farming.  So for those who don’t like to do much physical activity, you can just sit on a boat all day fishing and feel a whole lot better about yourself after.

Most people who exercise regularly already know that there are not only physical benefits but mental benefits as well.  There have been multiple studies that have shown regular exercise can help individuals with arthritis, diabetes, and even cancer.  Another recent study has shown that regular exercise can help relieve anxiety.  So if you are feeling anxious or depressed, a quick jog could help make you feel better. Most participants in the study felt less symptoms such as worry, apprehension, and nervousness.  Exercising for more than thirty minutes was best at reducing anxiety.  While exercise seems to be great for your body and mind, over exercising can also be a bad thing.

For the same reasons that exercise can help make you feel better, it can also become addicting.  Researchers believe that because exercise induces the release of neurotransmitters like dopamine and endorphins, it can become an addiction.  Excessive exercising can lead to unhealthy weight loss along with other issues.  In one study, researchers used two groups of rats, one active and one inactive group, to test their hypothesis.  After several weeks the rats were given naloxone, a medication for heroin overdose that causes immediate withdrawal symptoms. They found that the rats that ran the most had the worst reactions to the drug, while the inactive rats had very little response.  This study shows that while exercise is important to a healthy lifestyle, overdoing it can have potentially dangerous consequences.

Take Naps and Dream! May 1, 2010

Posted by Kyle in Biology, Neuroscience, Physiology.
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As finals are quickly approaching many students are spending a lot of time studying.  No matter how much you study, it is important to remember to get a decent amount of sleep.  A recent study by scientists at Beth Israel Deaconess Medical Center has shown that people who sleep right after attempting to learn a new task, more specifically those who dream about the task, perform better in later attempts.  Researchers hypothesized that by dreaming about a learning experience individuals would have improved performance on tasks relying on spatial memory. Researchers tested this hypothesis on 99 individuals by having them attempt a virtual maze.  They then had some individuals sleep while others stayed awake.  Individuals that slept and dreamed about some aspect of the maze performed 10 times better than other individuals. Individuals who remained awake and reviewed the path of the maze showed no improvement if they did not sleep.  These results show that something is happening while a person dreams that helps the brain sort out memory.

In another study related to learning and memory, researchers looked at how individuals evaluate their learning skills and memorization.  The researchers tested individuals by showing them a list of words and having them memorize the words. The individuals participating in the test predicted how well they would be able to remember the words.  The study showed that most of the participants underestimated their learning abilities and were over confident in their memories.  According to the researchers who performed these tests, Nate Kornell, an assistant professor of psychology at Williams College, and Robert A. Bjork of the University of California, Los Angeles, understanding how you learn and what supports learning is important to effectively manage the conditions of learning.

According to a separate study out from the University of California, Berkeley, napping can help restore brain power. The study showed that just 90 minutes of nap time can greatly improve learning ability later in the day. Past studies by the same research team have shown that pulling an all-nighter to study can decrease your ability to learn new information by roughly 40 percent. So as everyone prepares to finish off the semester, remember to not only study wisely but to also get plenty of sleep.  Hopefully I will be able to dream about organic chemistry and molecular genetics over the next couple nights, since this will apparently help me remember more. If not, at least maybe I can dream about golf and nap, and then maybe I wouldn’t be so bad at it.

How similiar are chimps and humans? April 30, 2010

Posted by Kyle in Behavior, Biology, Ecology, Evolution.
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Many researchers are interested in what makes chimps and humans different, as well as the similarities. A recent article on Science Daily highlighted two studies published in Current Biology on how chimpanzees deal with death.  The first study shows that chimps may have a more developed awareness of death than once thought.  Researchers observed how chimps responded to dying and dead chimps of their group.  In some cases, mothers would continue to carry and care for young that had died.  Researchers also observed how a group of chimpanzees responded to a dying female in the days leading up to her death.  They found that there were similarities between the chimps behavior towards the female and human behavior when an elderly relative is dying.

Chimp mother carrying mummified infant

Since chimps are our closest evolutionary relative, it makes sense that they would share some things in common with us.  In the second study researchers found that mothers would continue to care for their dead young, even months after the infant had died. As time went on, the mothers slowly began to separate from the corpses. These observations seem to indicate that there is a close bond between mother chimps and their young.  As Dora Biro of the University of Oxford points out, chimps resemble humans in many of their cognitive functions.  How chimps react to death and are affected by it could shed light on the evolutionary origins of human comprehension of death.

The similarities between humans and chimps starts with DNA.  Humans and chimps have very similar genomes. In fact, over 98% of a chimps DNA is the same as a humans, with most of the differences being in non coding regions. Another article on Science Daily addresses this similarity. According to Katherine Pollard, assistant professor at the UC Davis Genome Center and the Department of Statistics, the differences between humans and chimps is in how we use our proteins, not in the actual proteins.  Pollard and other researchers found “highly accelerated regions” of DNA when comparing the DNA of humans and chimps. These highly accelerated regions were areas of DNA that had evolved, however only a few of these regions contained genes coding for proteins. Researchers believe that one region may contain a gene important for brain development. As different as chimps and humans appear, there are more similarities than most people realize.

There are many researchers that have highlighted key similarities and differences in humans and chimps. With more research comes more interesting discoveries linking us to our evolutionary relatives. Some other interesting similarities have been pointed out recently, such as the understanding of fire as well as culture among different groups of chimps. More interesting articles on current research can be found on Science Daily.