|Dr. Guevara, Ecuador Institute of Endocrinology.|
Sunday, February 20, 2011
Tuesday, February 15, 2011
You know how when you get a new car (maybe not new, but new to you) and all of a sudden it seems like almost everyone on earth has that same car? You see one beside you in the Walmart parking lot, one stopped at the red light…you get the point. Science is exactly the same. Until some scientific topic stares you right in the face, you don’t take all that much notice. This was the same with me and the topic of strokes until this summer when my dad had one. Now every science news website I look at, I can’t help but read the ones with a headline relating to strokes. He first had a TIA (transient ischemic attack) which is also known as a mini-stroke. He was having slight trouble talking and seemed confused but everything was fine. Within a few days he had a stroke which caused one side of his face to droop and he lost his speech. He also couldn’t remember how to do simple tasks such as making the coffee he had always been making because he didn’t even know where to place the water. All of these crazy things made me wonder what the heck was going on inside of his body due to one tiny blood vessel is his brain being blocked.
New research indicates that the TIA my dad initially had isn’t necessarily transient like the name implies. It can actually have long lasting effects and hidden brain damage. The patients studied in this research all had resolved the effects the mini-stroke had on their motor systems within 24 hours and when clinically evaluated 14-30 days later they showed no impairment. Interestingly though, when the patients were subjected to a brain mapping procedure it unveiled that the brain actually had damage that lasted much longer than was once thought. The brain cells on the affected side of the brain showed changes in excitability making it harder for neurons to respond.
Since these TIA’s are often warning signs and the chance of a stroke in the days following a TIA is greatly increased, this mapping technique may be of great help. Doctors say that by refining this technique they may be able to identify which patients are at greatest risk for a stroke following a TIA and therefore direct treatment that is more suiting for each individual case. My dad unfortunately was one of the patients who did end up having a stroke following his TIA, but it has been over half a year since his stroke and he is making great progress. His cognition is almost back to normal and he can speak full sentences now. The recovering that is going on within his brain now is an even more remarkable thing with both hemispheres of his brain working to compensate. Information about this can be seen in the article The changing roles of 2 hemispheres in stroke recovery.
Monday, February 14, 2011
You can never forget your first kiss: the range of emotion surging through the body as your lips meet for the first time. As humans we are compelled to kiss, but what causes humans to want to exchange saliva and bacteria with another person? The answer to this is evolution and chemicals of course. In Sheril Kirshenbaum new book the “The Science of Kissing: What Our Lips Are Telling Us," it explains the origin and continuation of kissing. The scientific word for kissing is osculation and the definition of a kiss is the “mouth to mouth orientation of two individuals or the pressing of one’s lips on some other part of another’s body.” So now that we know what a kiss is, there are many questions that must be asked.
When did kissing begin and Why? Kissing has perplexed scientist for years. Even Darwin pondered the origin of the kiss. The explanation he asserted was kissing was innate or perhaps hereditary. This theory has been combated by anthropologists who would believe the kiss is a learned behavior. This kissing debate seems to stem from the many different reasons people kiss. Therefore looking at the evolution of the kiss is complex. It can be assumed that since the origin of the kiss cannot be pinpointed, the reasons for the behavior cannot be ascertained. This means that kissing was not likely developed from one single behavior. The scientific obscurity continues because kissing has no clear classification system that characterizes the different types of kisses or related behaviors. One theory of why kissing evolved was suggested by V.S. Ramachandran of UC San Diego, it says we are drawn to the color red. This was because our primate ancestors needed to detect ripe fruit. This recognition of red would allow them to survive and produce viable offspring. Therefore this attraction to the color propagates and attracts mates based on the color of the lips. It was found in a study that when male volunteers were shown photos of women wearing various lipstick shades. The men consistently chose red as the most attractive.
So after attractive and the lips meet, what exactly happens in the body? First a chemical cascade occurs, the pupils dilate, the heart rate increases and breathing becomes irregular. Dopamine is release, which excites the reward centers in the brain. A good kiss often leads to the rise in a chemical called oxytocin that leads to strong feelings of attachment. Kissing also allows for us to unconsciously assess the compatibility of our mate. Genes called the major histocompatibility complex (MHC) control the effectiveness of our immune systems. This means that if a diverse MHC is detected when kissing another person the connection may be more memorable. This is because this match would lead to offspring with healthy immune systems. In the end, nature is really choosing if a first date will lead to a second. Understanding the kiss is multifaceted, but it all comes down to the chemistry.
Tuesday, February 1, 2011
We’ve all seen the Grinch and you know what they say, his small heart grew three sizes that day. We all know how impressive we find it that the terrible Grinch used to have a heart two sizes too small and now he has the biggest of all. That is extraordinary until you hear it from me, octopuses have not one heart, not two, but three!!!
Okay now that I’m done with my poor attempt of trying to rhyme and be clever, let me explain to you what caused me to come across this information. The other day when reading Don't be Such a Scientist by Randy Olson, he told a story about an octopus using its beak to maul a diver who was trying to get a picture with the massive creature. It explained that the diver only got away after he finally relaxed because when he struggled with the octopus, its grip only got stronger and its bite harder. I found this interesting so I went searching for more information.
The biggest octopus is the giant Pacific octopus which is a whopping 110 pounds and can be up to 16ft in length. Although these creatures are huge, they are by no means dopey and stupid. Studies have shown that they can distinguish between shapes and patterns and have short- and long-term memory! They also have the ability to lose an arm in order to trick a predator and it will grow back in 6-8 weeks. Now on to its three hearts; one main heart is used to pump blood to the entire body while two are used to pump blood through the gills where waste is dumped and oxygen-rich blood is then pumped back to the main heart. Also, the blood of an octopus contains hemocyanin instead of hemoglobin so the blood is blue!
I tried to use the arouse and fulfill technique by adding the introduction about the Grinch to make people wonder what the heck this science blog was talking about. I am not very good at the "show me, don't tell me" and often find myself blurting out fact after fact, which I did the same here L But I tried to incorporate a video which may help to offset my ramblings. I also tried to use active voice when writing the blog. I need to work on transitioning from paragraph to paragraph and sentence to sentence.