Sunday, January 31, 2010

Right vs. Left

Right-handed and left-handed people do not see the same bright side of things

Although there is a universal correlation of “the right with life, right, positive and good things, and the left with death, inadequacy, negative and bad things,” recent studies have shown that not everybody believes this. A researcher at Stanford University, Daniel Casasanto, found that people who are left-handed tend to see the left as good, and the right with bad or ugly. This “goes against the enormous power of cultural context” that they live in. Professor Julio Santiago de Torres has done various studies which result in the belief that one’s sensory-motor experience in itself can create “abstract conceptual associations,” which lends people to favor the side that they use more often. Results demonstrate that experiences that give greater ease and fluidity in space generates a high level of stability for that side opposed to the opposite side, and the side that is easier is held in more goodness. I thought it was very interesting that left-handed and right-handed people had such difference of opinions on abstract ideas based on which hand they use more. I wanted to see for myself, so I asked my roommate to draw Satan and Jesus on a sheet of paper. Being right-handed, she proved this theory correct, and drew Satan on the left and Jesus on the right.

http://www.webnewswire.com/node/501904

Saturday, January 30, 2010

Shedding Light on Colon Cancer

Biomedical engineers have developed a new device to use for colonoscopies. Previously, colonoscopies were somewhat invasive. Doctors use a colonoscope that is 48-72 inches long with a camera attached on the end so it could record images of the small intestine. The new technique is less intrusive and uses a probe made out of a thin optical fiber which shines light onto the colon. A computer can analyze how the light backscatters to determine if the colon is likely to have cancerous polyps. This new technique is not only more effective, but it is also much more comfortable on the patient. Maybe this new technique will decrease the percentage of people who refuse screening because of the invasive nature of colonoscopies.

http://www.sciencedaily.com/videos/2008/0111-shedding_light_on_colon_cancer.htm

Friday, January 29, 2010

How Enlarged Hearts In Athletes Can Go Undetected

Twenty-six year old Bears DE, Gaines Adams, was one of many athletes that died unexpectedly from cardiac arrest. It was determined during Adams’ autopsy that he had a condition know as Hypertrophic Cardiomyopathy (HCM). HCM is a genetic disorder that affects 1 in 500 adults and is the most common cause of sudden death in athletes. HCM causes an abnormal enlargement of the heart due to thickening of the cardiac walls, which in turn causes the cardiac cells to shift into an erratic pattern. This erratic pattern causes abnormal electric signals in the heart that lead to potentially fatal arrhythmias.

Since Hypertrophic Cardiomypathy is fairly common, many people wonder why it isn’t detected in athletes during physical exams. HCM is commonly misdiagnosed in athletes because the heart becomes enlarged due to exercise. The difference between an enlarged heart due to exercise verses one due to disease is difficult to distinguish. The only way doctors can tell them apart is to do an EKG or an MRI to look at the heart. Diseased hearts become enlarged due to thickened walls while athletes’ hearts are enlarged due to larger chambers.

Armed with this information about HCM in athletes, many people are working to increase awareness about HCM. Some want an EKG or MRI to be a mandatory part of an athlete’s physical. Others want schools and athletic facilities to have AEDs on site in case of cardiac arrest.

I found this article interesting because we touched on the difference in the enlarged hearts of athletes and individuals with heart disease in class. Also, I was drawn to this article because a student in my high school died in football practice from HCM.

http://sportsillustrated.cnn.com/2010/writers/david_epstein/01/18/adams/index.html

Sunday, January 24, 2010

The Latest Front In the War on Arthritis by SHIRLEY S. WANG

The repair of damaged human cartilage has been something that numerous scientists and engineers have been working on advancing for the last years. Constance Chu and Lisa Fortier have been testing a new technique of this on former racehorses and rodeohorses. The cartilage repair treatment they are trying to replace is called microfracture. This new method uses concentrated stem cells. Other advancements include looking for biological markers that indicate cartilage damage and if it would be receptive to tissue regeneration.

Cartilage damage is a leading cause of osteoarthritis. While previous treatments for osteoarthritis include physical therapy, splints, arthroscopic surgery, and other methods, it would be more beneficial to prevent cartilage damage so that it doesn’t lead to osteoarthritis.

The repair and diagnosis of damaged cartilage tissue are both difficult. There are numerous issues in regenerating cartilage tissue. The cartilage structure is hard to mimic according to Dr. Chu which has made it so far impossible to grow new tissue in humans. Advancements in imaging technology has led to improvement in finding the damaged tissue. The current regenerative method: microfracture, “creates inferior tissue to what we are born with,” states Dr. Chu.

However, research and testing is being done in order to foster the regrowth of healthy tissue in humans. The different methods that Dr. Chu is investigating involve the usage of stem cells to repair the cartilage tissue. She believes that a higher concentration of stem cells will be more beneficial for the regeneration of human cartilage.

I wrote about this article because I am very interested in tissue engineering. With the technology and advancements we have made in the last few years, I know we are on the brink of many new discoveries in this field. The topic of damaged cartilage and tissue is also very interesting to me. I tore my anterior cruciate ligament in 11th grade and had arthroscopic surgery. A piece of my hamstring became my new ACL. There are numerous advancements to be made in both the diagnosis of and treatment of damaged cartilage. It is exciting to see how much progress has been made in this field in the last few years as well as to see how much further it will advance in the future.

http://online.wsj.com/article/SB10001424052748704350304574638132988984884.html

Saturday, January 23, 2010

Human Running Speeds of 35 - 40 mph May Be Biologically Possible


A study published in the Journal of Applied Physiology has found that the force limit with which the runner's leg can hit the ground is not the main factor limiting running speed, as previously thought. If the maximum force limit of the leg muscles is achieved, the maximum speed at which humans can run would increase to 35-40 miles per hour, much faster than the current world record holder and Olympic champion Usain Bolt's 28 miles per hour.
The best sprinters in the world apply 8 to 10,000 pounds of force with each step while running. This may sound like a lot, but experts say it is nowhere near the maximum force limit of the human body.
The study was done at the University of Wyoming and included testing subjects running on high-speed treadmills, and included activities such as running forward, backward, and hopping on one foot. They found that the time the foot and ground are in contact are near the same, while running forward and backward. However, the top speeds of these two different gaits are completely different. From this information, they think that the contractile speed limits of the individual muscle fibers affects the maximum speed of the runner. Using a mathematical model to represent the data, they project the highest running speeds of humans to be 35 to 40 miles per hour, using the maximum force the muscles can apply.
I found this article interesting because I never thought a human being would be able to run that fast. 40 miles per hour is almost Superman speed. Even though this only applies to the fastest people in the world like Usain Bolt, I still think it would be cool if the average person could run that fast.

Friday, January 22, 2010

Treating Brain Disorders With Light

Researchers at MIT are developing new tools called "super silencers" that may be able to treat various neuralogical disorders including epilepsy and Parkinson's disease or even brain injury. These tools function by shutting down the activity of the select neurons that express one of two new genes that will be inserted into them. This is a good method because it allows some neurons to be inactivated while others are still allowed to function, and it only uses different colored light rather than anything dangerous.

The two genes involved are called Arch and Mac, and they are taken from bacterial or fungal organisms. Yellow light activates the Arch gene, and Mac is activated by blue light. When these are activated, they code for proteins that prevent the neurons from firing action potentials. Only the neurons that have these specific genes in them are prevented from firing, meaning the rest of the brain cells are not affected. In this way, the researchers can fine-tune their control over which part of the pathway they want to interrupt.

So far, the research is concentrating on figuring out whether this treatment is safe and effective in monkeys. Soon, however, the scientists hope to be able to use this technique to treat people suffering from neurological disorders and to discover the pathways that contribute to various brain functions.

Sandhya Ramesh
VTPP 435-502

Link

Thursday, January 21, 2010

Using Nanoparticles of Attack Tumor Cells

Researchers from the University of Chicago’s Brain Tumor center have recently developed a novel technique for combating brain tumors. Their new method allows scientists and doctors to target brain tumor cells specifically, while leaving healthy cells unharmed. Dr. Rozhkova’s design uses titanium dioxide nanoparticles that are bonded to biological soft tissues. This nanodevice is then covered with antibodies that only target receptors on the tumor cells. The antibodies used in the design are specific only to the receptors on the malignant cell’s membrane. Thus, unlike chemotherapy, which attacks most cells in the body, Rozhkova’s treatment will leave healthy cells untouched. Once the titanium dioxide binds to the receptors on the tumor, a beam of light is focused on the target area causing oxidative radicals to be released from the titanium dioxide. These free radicals then interfere with the function of mitochondria in tumor cells, ultimately hindering the proliferation of the tumor cells. The titanium dioxide nanoparticles have also been found to attack the cell’s invadopodia, protrusions that allow the tumor cells to invade surrounding healthy cells. Although this new technique is still in the developmental stage, it shows much promise. Testing has shown that once the treatment is applied, there is an almost 100 percent cancer cell toxicity rate. Dr. Rozhkova hopes this new treatment will soon be ready for animal testing, and then clinical trials. She also said that her lab work proves that this method of treatment can be used for other types of cancers as well. Simply by replacing the antibody used in the treatment, this design can help stop the spread of many types of malignant cells. Dr. Rozhkova’s work is a prime example of how bioengineering is used to create new and more advanced treatment methods in the field of medicine.

This article can be found at: http://www.sciencedaily.com/releases/2009/08/090819123943.htm
Oscar Carrasco-Zevallos

Wednesday, January 20, 2010

Inflatable Device Stops the Bleeding

Some wounds are too deep for the conventional methods of bandages and tourniquets to prevent the excessive loss of blood that can lead to death. Fortunately, a new method of inflating a balloon like as is done in angioplasty might help seal wounds and save lives. The balloon is designed to mold to fit the wound for at least long enough to get the wounded person to the operating room. The device is not without its flaws however. Moving the device into or out of the wound can further damage tissue and inflation of the device can drive shrapnel deeper into the body or into healthy tissue. Nevertheless, any treatment for areas of the body that tourniquets cannot be applied to have promise of saving lives.

This article particularly interested me since it is a very tangible way in which lives can be saved. The circulatory system is also a growing interest of mine as I learn about the complexity involved in blood delivery throughout the body. While a simple concept to understand, applying our knowledge about the circulatory system is much more difficult and it is encouraging to hear about technology like that in this article that show that progress is being made in treating injuries.


http://www.technologyreview.com/biomedicine/24360/page1/