The heart is essentially the engine of the human body. The chambers of the heart contract and relax in order to move blood throughout the body (1).  The number of times the heart contracts and relaxes in a period of time is known one’s heart rate (1).  We associate the heart rate or contractions and a person’s pulse with life. If you have a pulse, then you are alive.

Until recently, if an individual had heart failure or heart disease their only options were to receive a heart transplant or die from the disease. Now, there are many researchers attempting to develop long-term artificial hearts. Many of which have made significant breakthroughs in their efforts

In 2011, Dr. Bud Frazier and Dr. Billy Cohn successfully implanted an artificial heart that creates a continuous flow of blood (2). As a result of the continuous flow the patient had no pulse (2).  Dr. Frazier’s studies also found that although the heart was not beating, the organs and tissues were not affected at all and worked properly with the alternate blood flow. The pair of doctors are continuing research and believe that the future will include life without a pulse.

(1) Tortora G.J. and B. Derrickson. 2012. Principles of Anatomy and Physiology. 13th ed., John Wiley and Sons

(2) “News and Publications.” Texas Heart Institute. Texas Heart Institute at St. Luke’s Episcopal Hospital, 23 Mar 2011. Web. 28 Feb 2013. <http://texasheart.org/AboutUs/News/2011-03-23news_tah.cfm

A New Look at Blood Transfusions

There are many reasons why people sometimes need blood transfusions. Blood transfusion is a process where blood from a person is transferred into another person (1). The most common reason why people require a blood transfusion is because they have lost too much blood, whether the blood loss was from a trauma accident or surgery (1). However, blood transfusions can also be done if a person suffers from severe anemia (1). Although blood transfusions can potentially save a person’s life, there are several risks that can occur. For example, after a blood transfusion, a person may develop what is known as a febrile non-hemolytic transfusion reaction, which is a fever that resolves on its own (1).

Recently, the University of Strathclyde in Glasgow developed a way to reduce the blood lose in patients during surgery by using a devise known as the HemoSep devise (2). The HemoSep devise collects the blood lost during surgery by using a blood bag which employs a chemical sponge technology and using a mechanical agitator to concentrate the blood collected (2). Once the cells are separated, they are put back into the patient by intravenous transfusion (2). In the 100 open-heart surgery clinical trials operation carried out, not only did the HemoSep devise drastically reduced the need for blood transfusions, it also reduced inflammation, something normally seen after a surgery procedure (2). Furthermore, there are still many clinical trials planned (2).With the CE mark, the device will now be sold in all European territories and any other regions that recognize the CE mark, as well as Canada (2).

I believe this new technology device will impact society in a positive way. Thanks to this new device, people will not have to risk their lives by getting a blood transfusion.  The less transfusions people have, the safer they will be from getting infections, viruses, or other risk factors that come from blood transfusions. Furthermore, with less blood transfusions needed people will not have to donate as much blood as before.  In my opinion, it is a win-win situation.

1.)    “What is a Blood Transfusion?” News-Medical.Net . (2013): n. page. Web. 22 Feb. 2013.

2.)    “New technology to transform blood processing.” strath.ac.uk. (2012): n. page. Web. 22         Feb. 2013.

For the heart to contract several steps have to occur, but one main component used to make the heart contract is calcium. Calcium binding allows for actin and myosin to develop tension which influences the strength of the heart contraction (Tortorra and Derrickson). However, substances can alter a change of calcium flowing through the calcium channels leading the heart to beat too fast or too slow in a condition called arrhythmia (Tortorra and Derrickson). Many diseases and conditions are associated with arrhythmia, such as sudden heart attacks in healthy people, which has researchers wondering what causes this.

With the utilization of powerful X-rays, University of British Columbia researches have managed to create an animated model that shows how gene mutations can affect the beating of the heart (ScienceDaily).  After calcium enters the muscle cells of the heart a special protein is in charge of opening the calcium channels that allow for calcium to be released and consequently make the heart contract (ScienceDaily). A gene mutation in the special protein controlling calcium release has been linked to arrhythmia, and other cardiac problems (ScienceDaily). With the construction of a 3D animated model of how the gene mutation of the special protein affects heart contraction, researchers can now better understand how this mutation can be corrected, and therefore possibly save lives (ScienceDaily).

Our hearts beat to the sound of calcium, but gene mutations such as the one that affects the special protein of the calcium channels can lead to serious health risks, and that is why the creation of a 3D model is so important. With a 3D model of the gene mutation researchers are allowed to visibly see such a mutation and watch it in action as it would occur in real life. Therefore, from this model, possible treatments can be made that would prevent or diminish heart related conditions caused by the gene mutation in the special protein. Arrhythmia, at its worst, can cause death, but further research and the utilization of this 3D model can help lower arrhythmia related conditions of the heart (ScienceDaily).

Tortora G.J. and B. Derrickson. 2012. Principles of Anatomy and Physiology. 13th ed., John Wiley and Sons

University of British Columbia (2013, February 17). Heart condition: Arrhythmia culprit caught   in action. ScienceDaily. Retrieved February 25, 2013, from http://www.sciencedaily.com/releases/2013/02/130217134214.htm

Color Vision

In vision, color perception depends on wavelength. The photoreceptors that are involved in vision are rods and cones. Rods allow us to see dim light but don’t provide color vision in dim light so we only can see black, white, and shades of gray (Tortora & Derrickson). There normally about 120 million rods. Cones are stimulated by bright light which produces color vision. There are normally 6 million cones (Tortora & Derrickson). In essence, different people may see one subject in many different ways.

In a study on the evolution of color vision conducted at the Howard Hughes Medical Institute, researchers introduced a human gene into a mouse chromosome. The human gene code was for a light sensor that a mouse normally does not have (Nathans). The goal of th experiment was to see if a mouse’s brain was capable of using the human photoreceptor to see just as many colors as we can. The mice used in this study actually exceeded their expectations. They had to test the mice to see how well their color vision had developed so they showed them color panels. The mice chose the correct panels in 80 percent of the trials (Nathans). The study is what led them to the conclusion that the trichromatic color vision that we now enjoy came from distant ancestors of all primates. There are consequences of trichromacy as well. We perceive what we see on television and computer screens as a full spectrum of color when in reality the colors are just mixtures of red, green, and blue pixels. After reading this research, the evolution of color vision is clearly a complex process.

The study of the human eye is a task itself when there are so many different components that function around the eye. The retina can provide the most information when studying color vision. Maybe one day some researcher will be able to explain what all the human eye is capable of because without color vision everyone would only see black, white, and shades of gray. No one wants to live in a dim world.

Gerald J. Tortora and Bryan Derrickson. Principles of Anatomy and Physiology. 13^thed., John Wiley and Sons, 2012.

Nathans, Jeremy. “HHMI News: Genetic Studies Endow Mice with New Color Vision.”HHMI News: Genetic Studies Endow Mice with New Color Vision. Howard Hughes Medical Institute, 23 Mar. 2007. Web. 12 Feb. 2013. <http://www.hhmi.org/news/nathans20070323.html>.

LASIK surgery is an increasingly popular alternative to wearing glasses or contacts. It reshapes the cornea and changes the focusing power. The intent of the surgery is to correct the curvature of the cornea for conditions that include farsightedness, nearsightedness, and astigmatism (Tortora & Derrickson). Nearsightedness can be corrected by using a concave lens that diverges the light rays coming in so that they are in focus directly on the retina. In farsightedness, the correction is a convex lens that converges the light rays entering to focus directly on the retina (Tortora & Derrickson). After surgery, however, there could be side effects such as dry eyes and sensitivity to light.

There are many different studies being conducted involving the sensitivity of the cornea after the surgery takes place. In one particular scientific study, patients were examined to investigate whether LASIK surgery was the cause of patient’s cornea sensitivity and dry eyes. Twenty patients who had undergone myopic LASIK surgery two to five years previously were placed with ten people who had not received the surgery. The cornea sensitivity was assessed by using a non-contact esthesiometer. (PubMed)

The degree of dry eye symptoms was significantly higher in patients who had received the LASIK eye surgery treatment, rather than the patients in the control group. The majority of patients also reported ongoing symptoms, although the testing for that in particular was not conducted. (PudMed) Some claimed they had never had such symptoms until after the surgery.  It appears that the LASIK surgery could have played a role in the tear deficiency of the patients, as well as the sensitivity.

Works Cited:

Gerard J. Tortora and Bryan Derrickson. Principles of Anatomy and Physiology. 13^th ed., John Wiley and Sons, 2012.

Journal of Refractive Surgery from PudMed.gov 2007. <http://www.ncbi.nlm.nih.gov/pubmed/17455828>

The individual components of the eye work in unison, with each part playing a vital role in providing clear vision.  The cornea acts as the eye’s main focusing segment.  It takes a widely diverging ray of light and bends it through the pupil which is surrounded by the colored iris.  The eye is very complex, and with this complexity various problems can occur.  With new technology, doctors are able to restore many forms of impaired vision.

A new study completed in Kobe, Japan looked into the development of mammalian eyes from stem cells.  Yoshiki Sasai grew what is now known as an optic cup using human stem cells.  This breakthrough was encouraging due to the ability for Sasai to grow three-dimensional tissues unlike the two-deminsional sheets that were being developed.  Observing the optic cup, structural similarities were seen when compared to normal development of an human in vitro eye.  Sasai was impressed to notice that layers of the eye were grown in the same sequence without his aid.

This new achievement could aid scientists in a clinical setting aiding to the increased successes in transplanting stem cell photoreceptors into mice.  This transplant only offered rod receptors that would only give unclear images.  Sasai’s optic cup is being looked at to one day integrate both photoreceptor tissues into humans.

Yoshiki, Sasai, Eiraku Mototsugu, et al. “Self-organizing optic-cup morphogenesis in three-dimensional culture.” Nature. 472.7341 (2010): 51-56. Web. 28 Jan. 2013. <10.1038/nature09941 >.

Tortora, Gerard J., and Bryan Derrickson. Principles of Anatomy and Physiology. Hoboken, NJ: John Wiley & Sons, 2010. Print.

There are many reasons as to why people go blind. For example, blindness can occur because the lens of the eye became cloudy, which prevents light from entering the eye, or because the retina got degraded and deteriorated, which affects the perception of images (1). Another cause of blindness could be caused by a change in eye shape, which alters the projection of an image, or because of damage to the optic nerve, which disrupts the flow of visual information to the brain (1).  Blindness can also occur because of an eye injury or trauma (1). However, the leading cause of blindness in the United States is caused by eye diseases (1).

Because technology has advanced so much in the past few years, people with failing vision can now get a corneal transplant. However, now there is an even better solution to improving eye vision. The University of Tuebingen in Germany has developed a chip that can be implemented into the eye which transforms images into electrical impulses that are sent to the brain, which allows the person to see (2). The clinical trials for the chip implant were done on people who suffered from retinitis pigmentosa, a hereditary condition that destroys the retina (2). The results showed that out of the eleven people who received the surgery, five were able to see or distinguish objects (2).

Although this new chip implant discovery does not work a hundred percent, I believe it is only the beginning. With this new discovery, people who have suffered from blindness can now have the hope that they will be able to see once again. This new discovery will not only provide hope to the family of the victim, but it will also give the victim confidence and raise his or her self- esteem.  He or she will once again be able to live his or her life however he or she wishes. Furthermore, with technology improving every day, I am sure one day people will not have to suffer from blindness anymore.

1.)    Thompson, Dennis. “What Causes Blindness? .” EverydayHealth.com. (2010): n. page.      Web. 30 Jan. 2013.

2.)    Bukowski, Jack . “Let There Be Light: New Technology Enables Some Blind Patients to   See .” InsidersHealth.com. (2011): n. page. Web. 30 Jan. 2013.

Hearing is a process in which the hair cells in the cochlea play a very important role.  Hair cells are stimulated and moved by a vibrating sound wave and they  convert the vibration into an electrical signal that is interpreted by our brain as a sound (Tortora and Derrickson). So as a result of their important role in hearing, when the hair cells are damaged by extended contact with loud noise deafness can occur. A cochlear implant is usually the treatment performed to those with damaged hair cells to recover some hearing (Tortora and Derrickson). However, the Massachusetts Eye and Ear and Harvard Medical School researchers have  successfully performed an experiment in which with the use of a drug managed to regenerate hair cells in deaf mice ( ScienceDaily).

Researchers used a group of deaf mice to test a drug’s effectiveness of turning supporting cells into new hair cells in the cochlea. The drug used inhibited a signal in the Notch protein which surrounds hair cells, and as a result of the inhibition the surrounding cells began to turn into hair cells (ScienceDaily). Afterwards, the deaf mice recovered some hearing because of the regenerated hair cells, and the drug was found to be what caused this improvement in their hearing (ScienceDaily). With the use of an analyses  that showed increase hair cells in the deaf mice ears, researchers further supported the regenerating power of the drug that was used (ScienceDaily).

Researchers are excited to see the results that this drug produced in adult mice because it is the first time hair cell regeneration has been achieved in adult mammals (ScienceDaily).  Implants, surgeries, and other types of treatments for hearing loss can become a thing of the past with this new found research. With further improvements of this drug and more testing, this drug could be used to correct any hearing problems caused by the damage or absence of hair cells. However, for now we should all take the proper precautions to take care of our hair cells by minimizing the exposure to loud sounds for an extended period of time.

Sources:

Massachusetts Eye and Ear Infirmary. “Sensory hair cells regenerated, hearing restored in noise damaged mammal ear. “ScienceDaily, 9 Jan.  2013. Web. 27 Jan. 2013. http://www.sciencedaily.com/releases/2013/01/130109124201.htm

Tortora G.J. and B. Derrickson. 2012. Principles of Anatomy and Physiology. 13th ed., John Wiley and Sons