Key Leukemia Defense Mechanism Discovered

A team of researchers at Virginia Commonwealth University Massey Cancer Center have discovered a mechanism by which leukemia cells resist treatment. Typically histone deacetylase inhibitors (HDACIs) work to cause cancer cells to apoptose. It’s been known for a while now though that the effectiveness of HDACIs is reduced because it activates a defense mechanisms that prevent the normal chain that cause them to apoptose through the signaling pathway NF-kB. It used to be thought that this was caused by receptors on the cell surface, but the groups discoveries show that it is caused by a defect induced in DNA by HDACIs that modifies the protein NEMO and subsequently signals the NF-kB pathway. Through preventing the modification of NEMO it is possible to prevent the defense mechanism and dramatically increase the effectiveness of HDACIs.

The group’s goal is to move findings to the bedside quickly and there are already drugs in development that will disrupt the NEMO/NF-kB pathway and will require research about their safety. I’m particularly interested in the development of these drugs and therapies because I have a family history of leukemia; I have an uncle that passed away from it and my gradpa’s leukemia was in remission but is coming back.

http://www.sciencedaily.com/releases/2010/09/100930143351.htm

Improvements in heart repair patches from stem cells

Engineering patches are fabricated for heart repair, but the problem is that the cells would die after they were transplanted to the heart's core. This is because nutrients and oxygen were not able to travel to the center of the patch. Researchers began to experiment and added different types of cells to the heart patches. The new cells came from the lining inside blood vessels and cells that provide muscular support. These cells also came from embryonic stem cells or other mature sources. It was found that the new patch contained tiny blood vessels so that nutrients and oxygen could flow to the middle of the patch.

The advantages of the new tissue produced is that it is more stiff. The stiffness resembles more of heart muscle cells and allows the blood to fill the heart before it contracts. This created new connective tissues to transport the blood more efficiently. Another advantage of the new tissue cells is that the tissue actively contracts, very similar to an actual human heart and could keep up with the heart beats.

One problem that has not been overcome is the fact that the human body may still reject the transplant of the engineering patch unless the patient takes medication for the rest of their life. This is still an obstacle that is being researched till today.

The new engineering tissue can be used to repair damaged areas from heart attacks or birth defects by regenerating tissue cells from stem cells. This research could lead to the development of a full human heart from human embryonic stem cells, blood vessel linings, and fiber cells.

I found this article interesting because the regeneration of new tissues from stem cells is an area of important research in the biomedical field. The thought of being able to repair heart muscles crucial in the cure of heart related diseases. Being able to understand and get a better insight of stem cell research inspires me as an individual to create new and better ideas for the future.

Article: http://www.biology-online.org/articles/major-improvements-made-engineering-heart.html

On new lab chip, heart cells display a behavior-guiding ‘nanosense’

Heart disease is on the rise as human life spans increase with rapid progression in the medical field. Deterioration of cardiac muscle can be caused by a plethora of diseases or simply aging, and many times, this can be fatal. The problem with reparation of cardiac tissue is that it is very fragile, and also very complex. Using stem cells to “grow back” heart tissue seems like a simple concept, because somatic stem cell therapy has been done numerous times, but transdifferentiation of stem cells for the heart has many complications. In addition, heart tissue is very difficult to emulate, and as such has posed a big problem for the millions of patients with heart disease or in need of therapeutic cardiac procedures.

Biomedical engineers at Johns Hopkins University, in conjunction with colleagues from Seoul National University in Korea, have developed a laboratory chip with nanogrooves which allow for heart cells to be cultured and develop to be closer to actual heart tissue than ever before. This tool not only allows researchers to study heart diseases more readily and develop remedies, but also opens up doorways for new therapies or diagnostic tests for heart disease.

I found this article very interesting because my uncle and grandfather are both affected with heart ailments and have both been hospitalized as a result. I believe that had their heart disease been detected earlier or had there been a better therapy or remedy for their respective cardiac problems, they could have avoided being stranded in a hospital bed. With the potential development of new procedures or diagnostic tests using this lab chip, the ability of hospitals and cardiac surgeons to treat patients could greatly increase.

Source:

http://insciences.org/article.php?article_id=7950

Implantable Miniature TelescopeTM -P050034

This summer the Food and Drug Administration approved the market of an implantable miniature telescope produced by VisionCare Ophthalmic Technologies. This device is designed for patients of seventy five years or older that suffer from severe vision impairment due to age-related macular degeneration (AMD). Surgeons place one of the two available telescope models, one with 2.2 times magnification and the other with 2.7 times magnification, into only one of the patient’s eyes. The IMT works by magnifying the image and directing it onto the healthy retinas of the eye. Although the device does not cure AMD, the IMT does improve vision significantly. Typically, patient’s vision improve by at least five letters on the charts.

Evolving Robots show life-like behavior

For those who enjoy the integration of biology and technology, a company based in Switzerland is demonstrating and studying the effects of robotic personality genomes. Flipping the normal order, by improving technology with biology, engineers from the University of Lausanne, Switzerland are using a program-perfecting method as old as life itself.

Darwinism, the messy, trial-and-error, results-focused system of survival of the fittest can be used to program robots; no intelligence required. The researchers at the University of Lausanne, engineers Sara Mitri, and Dario Floreano, and evolutionary biologist Laurent Keller, have built small robot platforms, with modular sensors, and a special processor. Instead of a traditional number-crunching logic machine, the ‘brain’ of these robots consists of ‘neurons’ attached to the sensors and their wheel-tracks.

The robots are then assigned ‘tasks,’ where they are given a basic program to start with, and the researchers created an arbitrary point system that rewards points for “positive behavior” and takes away points for “negative behavior”. The best scoring robots have their program copied to all of the other robots (the new generation) with some slight randomization. This successfully generates a new generation with heritable traits refined by a selective pressure. In short, Darwinism. It should be explicitly stated that after the initial program, there is no intelligent editing of the code. It is changed and improved only through combination, mutation, and selective pruning.



In this particular experiment, there were 100 groups of 10 robots. The robots were equipped with an Omni-directional light sensor, ground sensors, and a light ring. 11 neurons were attached to the sensors, and 3 more attached to each tank tread and the light. The ‘neurons’ were interconnected by 33 ‘synapses’. The ‘genetic code’ that determines the robot personality is an list of 8bit numbers, one for every ‘synapse’, that regulates the strength of the connection between the two joined ‘neurons, creating a variable program. The top 200 scoring robots from each trial would have their programming combined, randomized, and reintroduced as the next generation.

Their goal was to find a ‘food source’ while avoiding ‘poison’. Two objects with differently colored rings of light represented the food and the poison. Robots were given points for spending time up against the food, and given negative points for time spent in proximity of the poison. After every trial, points were added up and the best robots had their codes mixed together, changed randomly, and then given to the next generation. Simulating the survival of positive traits being combined and mutated with every generation. A link to a short video of the process is provided below.

The explanation seems dry at first, but the results are astounding. While a consciousness isn’t possessed, recognizably life-like behaviors presented themselves. Initially the robots were programmed to follow the light emitted by others, and to light their blue light when they found the food source. After only 9 generations, the robots became very proficient at detecting the light and moving towards it, making the light a very important and useful tool to effectively find the food. Room around the food source is limited however. Robots became so proficient, that initial food finders would sometimes be pushed out of proximity by attracted robots, giving them less points, and thereby cleansing them from the gene pool. By the 50th generation, robots were turning on their lights outside of the area of the food more often than inside, and the light conversely became a poorer source of information. Many robots learned to keep their light off entirely; a complete change from the original programming. The robots were deceiving one-another!

This remarkably animalistic-adaptation arose from random traits with selective pressure, demonstrating Darwinism in miniature. As one would expect in a natural environment, the robots further adapted to the deception, learning to ignore the misleading lights more and more. This lead to less selective pressure against shining one’s light near the food, because everyone else would ignore the signal. As a result, about 60% of the robots in the 500th generation lit their lights when in proximity of the food. This yielded no real benefit, but survived because it was more or less benign. In short, genetic drift. With the robots now relatively proficient at ignoring each other and finding food, the selective pressure decreased significantly. Much like with humans, where our intelligence allows us to overcome most obstacles using tools, Darwinism is made less effective at improving the populace because a minimum ability of survival is present in every robot. Therefore diversity found within the population is less due to beneficial traits, and more due to random genetic mutation that isn’t selected against.

I found this research to be interesting because I enjoy seeing scientific principles at work. Darwinism, one of the most well established and unfortunately contested systems, is so simple that it can be applied to almost any quality-dependant system. In other experiments by this lab, predator-and-prey behavior evolved to a very animalistic pattern, including lying in wait. In another, a maze robot initially so defective that it actively sought out walls, was able to navigate a closed space as well as a mouse. This method not only provides an interesting demonstration, but opens the door for practical applications. This non-cognizant learning could be applied to AI programs to work as a behavioral learning. The problem with Darwinism is that it takes generations to function, which is decades for most organisms, but only seconds for computer programs. Difficult programing problems could be solved by trial-and-error, creating novel new coding methods, and optimizing systems already at work. For someone who is split between a love of computers and biology, and who chose biomedical engineering as a compromise, this is very exciting.

Sources:
Laboratory of Intelligent Systems of the University of Laussane websie.
"Not Exactly Rocket Science" blog: http://scienceblogs.com/notrocketscience/2009/08/robots_evolve_to_deceive_one_another.php?utm_source=selectfeed&utm_medium=rss

Link to report on the study: http://infoscience.epfl.ch/record/139388/files/PNAS-2009-Mitri-0903152106.pdf?version=1
Link to the company website: http://lis.epfl.ch/
Link to video: http://www.youtube.com/watch?v=-M5oc4cBtCg

Hip dysplasia susceptibility in dogs may be underreported, according to comparative study

Canine Hip Dysplasia (CHD) is a genetic disease that is common in many large dog breeds in which the hip joint is deformed, leading to pain and difficulty walking. For generations upon generations this disease has been impossible to eliminate. This article explains a study conducted by the University of Pennsylvania Hip Improvement Program of a diagnosis method different from the conventional method of x-raying the dog in the ventrodorsal hip-extended view. The study suggests that a method in which a measurement of the distraction index(DI), the distance from the femoral head (the ball of the ball and socket joint) to the center of the acetabulum (the socket) divided by the radius, is taken from a different radiologic view. Joint laxity, or joint instability, is quantified by this measurement. The higher the DI of a dog, the more joint laxity, thus the more likely it is to develop CHD. The greatest benefit of the method over the other is that the measurements can be taken as young as 16 weeks into a dogs life, unlike the more common method of examination that may not indicate CHD development until the dog is several years old. This would finally be a step in the right direction for potentially elimating the disease, since breeders could diagnosis the puppies early on, making sure they are not bred and pass the gene on further.

I found that this study has been considered for possibly using this alternative method in humans also, since dog's with CHD provide excellent models of humans with hip osteoarthritis.

I have a 4 year old labrador retriever, who was just recently diagnosed with CHD from a ventrodorsal hip-extended x-ray view. I have been reading up on the disease and treatments, so when I found this article I thought it was especially interesting.

I originally found an article on the topic from the link:
ncbi.nlm.nih.gov/pmc/articles/PMC1410725/ called "Canine and genetic assessments of hip joint laxity in the Boykin spaniel" but I found a much more interesting article from the next link:

physorg.com/news202642643.html

Harvard Method Turns Skin to Stem Cell Alternative With Less Cancer Risk

Harvard Stem Cell Institute scientists have made synthetic mRNA to get four proteins into skin cells which transform them into cells with traits identical to stem cells. Four years ago Shinya Yamanaka of Kyoto University in Japan developed induced pluripotent stem, or IPS, cells. His method uses viruses to transform these skin cells into stem cells. These are being used to test new drugs, but can't be used in patient therapy due to their cancer risk. In the new method, the mRNA

degrades quickly, disappearing before it can cause problems.

This is interesting to me because I believe stem cell research should be explored, but as many people do, I have reservations about destroying embryos. If we can find alternatives to this, we can remove the political aspect of stem cell research.

http://www.bloomberg.com/news/2010-09-30/harvard-method-turns-skin-to-stem-cell-alternative-with-less-cancer-risk.html

New Artificial Skin Could Make Prosthetic Limbs and Robots More Sensitive

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Stanford scientists were able to successfully create a 'skin' by placing a rubber material between two parallel electrodes. This skin is very sensitive, capable of detecting the slightest touch. How this material differs from previous attempts is that it uses a molded grid of pyramids instead of smooth rubber. This allows the material to deform when placed under pressure and then return to its original shape. When the smooth rubber was put under pressure it was merely compressed deforming the internal structures and hindering it useless.

The skin is able to sense touch because the rubber material between the electrodes stores charge and when it is placed under pressure the charge changes, the change is then detected and constitutes the sensation of feeling. The molding of the skin into different shapes allows it to sense different magnitudes of pressure much like actual skin.

There are many different potential application of this skin ranging from integrating into a device to detect whether or not a driver is awake at the wheel, to applying it to bandages so doctors could tell if they are tight enough.

I found this article really interesting because I was unaware of the advancements that had been made in this field of biomedical engineering. I've always been interested in the improvements made in developing the mechanical prosthetic arm, but I never considered the possibility that the eventual final product would be able to sense touch. The potential applications of this 'skin' are limitless, I for one think it would be epic if this technology were integrated into the machine surgeons can use to operate on a patient from a different location.They would literally be able to 'feel' what they were doing while being halfway across the world. I am definitely going to continue following the advancements in this technology.

Source: http://www.sciencedaily.com/releases/2010/09/100913141537.htm

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by Stanford University. The original article was written by Louis Bergeron.

Eye Doctor Says Laser Surgery Safer Than Contacts

Traditionally, the popular thinking about vision correction has been that corrective lenses are safer than laser eye surgery. This article reevaluates the risk associated with both forms of vision correction, based on several large-scale studies. Although several advances make both methods increasingly safer, William Mathers, M.D. and professor of ophthalmology suggests that there is a greater chance of suffering vision loss from wearing corrective lenses than from laser vision corrective surgery.

It is difficult to compare the risks of corrective lenses with those of laser surgery because the risks associated with lenses are much more “long-term” than the immediate effects of laser surgery. Wearing corrective lenses puts users at a greater risk of obtaining an eye infection; in the serious cases this can lead to eye removal. Data presented in a study in Lancet shows the lifetime risk of bacterial karatisis, an infection that causes inflammation in the cornea sometimes leading to vision loss, to be 1 in 100 for users of corrective lenses. This risk is increased by improper cleaning or wearing lenses overnight.

It is easier to calculate the risks of laser surgery. Mathers looked at a large-scale study of military personnel who received laser surgery involving more than 32,000 U.S. armed forces members that was published in the journal Ophthalmology. The study reported that 1 in 1250 of the participants found a loss of vision by one level in the eye chart and no one who lost two or more lines of vision, which would be less common but much more significant. In comparing this study to the studies on corrective lenses, he determined that laser surgery is likely safer than wearing contact lenses long-term. The article concludes that both of these methods of vision correction are continuing to become safer as more advancements are achieved in both areas.

I found this article interesting because I have very poor vision and have been wearing corrective lenses for several years. I’ve been considering laser surgery correction in the future but I’ve always been nervous about the risks involved. After reading this article, I am more motivated to research the risks and benefits associated with both methods of vision correction.

Source: http://www.sciencedaily.com/releases/2006/10/061010022541.htm

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by Oregon Health & Science University, via EurekAlert!, a service of AAAS.

Preventing the Spread of Cancer Cells

Researchers at Weill Cornell Medical College claim to have found the potential for a new class of anti-cancer agents through macroketone. The researchers published their findings in the online edition of the journal Nature. They have found that these new anti-cancer agents can stop the migration of metastatic tumor cells and therefore the spread of cancer.

The specific study involved implanting cancer cells into populations of mice and then treating them with small molecules called marcoketone. They found that the treated mice with cancer lived to a full life span in contrast with the control group which all died from metastasis. Even in mice that had the marcoketone introduced a week after the implantation of cancer still had an 80% block of metastasis. The researches are confident that this study is indicative of a new field of cancer treatment that is developing to specifically stop cancer metastasis. Dr. Haung, leading the research team at Weill Cornell, says, "More than 90 percent of cancer patients die because their cancer has spread, so we desperately need a way to stop this metastasis." Macroketone was developed from migrastatin, a natural substance that was isolated from Streptomyces bacteria by Japanese researchers. The researchers had noted that migrastatin had a weak inhibitory effect on the migration of tumor cells. Dr. Huang and his team took this substance and made synthetic versions that are a "thousand-fold more potent" than the migrastatin original.

The mechanism of macroketone is that it targets an actin cytoskelatal protein known as fascin which is needed for cell movement. Fascin bundles actin filaments together in order to make a kind of "foot" that can be used by a cancer cell to leave a primary tumor. The macroketone latches onto fascin and prevents actin fibers from adhering to one another which prevents this cell movement altogether. It is important to note that this treatment did not stop cancer cells from growing or forming tumors but it did prevent the spread of the cancer. The research team hopes that macroketone can be used in conjunction with another drug that would act on tumor cell growth. Dr. Huang also said about the minimal side effects that, "fascin is overexpressed in metastatic tumor cells but is only expressed at a very low level in normal epithelial cells, so a treatment that attacks fascin will have comparatively little effect on normal cells -- unlike traditional chemotherapy which attacks all dividing cells."

I found this article to be interesting because of the disease that was being discussed: cancer. Because cancer is such a deadly and widespread disease, there is a large amount of interest in investing time and money into the research of this disease. This leads to new discoveries being made everyday about the nature of cancer and the strides made in how to treat this disease. I also enjoyed the article because it dealt with taking a new perspective on cancer treatment. Instead of trying to treat tumorous tissue or individual tumors, the research team is attempting to control the cancer by not letting it spread through the body. Any new approaches to treating cancer are a step in the right direction to learn more about this disease.

Article Source: http://www.medicalnewstoday.com/articles/185482.php
Alexander J. Quante '13 -- VTPP 434

A Filter Paper Method for the Detection of Plasmodium falciparum

Malaria kills approximately one of the 250 million that infects every year. This disease endemic of tropics is most common in regions of little economic development like Sub-Saharan Africa. Nowadays, blood film microscopy, the most common ─and seemingly effective─ diagnosis procedure for malaria diagnosis involves the preservation of blood. Interestingly, the most malaria-ridden regions in the world are not exactly the places where you will find the means to do so. In these cases, "dipsticks " or rapid malaria-diagnosis paper tests are used. However this procedure has a few disadvantages. First, it is not a quantitative method, since it only detects if malaria antigens are present in the blood. The other downside of these tests is that they only detect the infection when the malaria parasite (Plasmodium falciparum) is mature; thus carriers of the immature forms of the parasite cannot be treated, so the disease keeps spreading. A few years ago, a new method for the diagnosis called RT-PCR (Reverse Transcription-Polymerase Chain Reaction) appears to have solved the two later problems, and it is even more accurate than microscopy. Sadly, it still requires specialized equipment and the preservation of blood.

Consequently, researchers like David Sullivan and Nirbhay Kumar at the John Hopkins Malaria Research Institute have experimented with the application of the RT-PCR method using dried blood instead frozen samples. They utilized blood-soaked filter paper to collect the samples. There study showed that malaria parasites can be detected from these sun-dried paper samples with a similar detection limit to that of frozen blood samples. Also, the process will cost less since there is no need for RNAlater treatment (part of the RT-PCR method) of the sample and cold chain transportation if filter paper is used.

In sum, this article is an example that sometimes cutting edge & complex solutions do not apply to all cases, and alternative and more practical pathways can make the difference in effective diagnosis and treatment.

Reference:

Godfree Mlambo, Yessika Vasquez, Ralph LeBlanc, David Sullivan, AND Nirbhay Kumar. "A Filter Paper Method for the Detection of Plasmodium falciparum Gametocytes by Reverse Transcription–Polymerase Chain Reaction." The American Society of Tropical Medicine and Hygiene 78(1), 2008, pp. 114-116. PubMed.gov. Web. 29 September. 2010

Source:

http://www.ajtmh.org.lib-ezproxy.tamu.edu:2048/cgi/content/full/78/1/114

Predicting the Effects of Blood Flow Rate and Size of Vessels in a Vasculature on Hyperthermia Treatments

Hyperthermic treatments are a new frontier in the fight against cancer. The treatment involves raising temperatures of a specific tumorous site over a period of 45-60 minutes to help destroy cancerous cells or increase the effectiveness of radioactive treatment in the area. The promising treatment works through increasing blood flow in the area, making the tumor cells more susceptible to treatments such as chemotherapy or radiation therapy.

The article posted takes a look at a controversial equation that's been used for over half a century termed Pennes Bio Heat Transfer Equation (PBHTE) to measure the temperature distribution of tissue. This equation has been used widely during hyperthermia treatment to ensure proper temperature levels, however the equation does not take into account the thermal distribution of blood vessels. The article attempts to take a step towards correcting this flaw through 3-D computer modeling, and through the combination of the conduction equation of tissue and the convective energy equation. The method developed was termed the countercurrent blood vessel network (CBVN) model.

The results show that the size of local blood vessels does not have a significant effect on the local temperature. During hyperthermia therapy, the vessel size has no impact on the power consumption if blood flow rate is constant. However, in thermally significant blood vessels, the power is used to heat the blood vessels, leading to higher temperatures in the blood vessels when using PBHTE as a model.

This article interested me because of a couple reasons. First, I had never heard of hyperthermic cancer treatments until this article. At first read, it seemed like this therapy could fall under the category of alternative medicine, but after reading more about it, the treatment seemed more and more viable and effective. Second, this article was different from other articles I have recently read because of its close work with numbers and computers, as opposed to petri dishes and scaffolds. Implications that one article type is better than the other are moot, however the argument that this article does a good job showing the intertwining of both engineering and biology stands strong.

Metal Form could overtake Titanium

Replacing bones and knees with tianium is the accepted standard today. New materials such a metal foam might be used to replace the rigid titanium. Researchers at North Carolina University are developing these new biomedical implants that have many benefits over titanium.
Titanium is relatively heavy compared to the metal foam. It is "even lighter than solid aluminum and can be made of 100 percent steel or a combination of steel and aluminum." In addition to the added weight, titanium is rigid. This modulus elasticity of the titanium is much larger than the bone. Modulus elasticity is the "material's ability to deform when pressure is applied and then returned to its original shape when pressure is removed." Titanium's modulus of elasticity is about 100 GPa. The metal foam has modulus "between 10 and 30 GPa" which is similar to bone. This means that titanium will take most of the load when a force is applied which causes the surrounding bone cells to die. Eventually the implant will loosen and will fail. The metal foam however has a rough surface allowing bone cells to grow within the foam and "will increase the mechanical stability and strength of the implant inside the body." The metal foam will not loosen within the bone thus making the replacement a better fix.
This article was interesting to me because I know several people who have had to have knee replacements. I knew these people were in pain before the operation and couldn't walk as well. After the surgery and rehablitation, their knees were almost as good as new. I didn't realize that the probability of another knee replacement is quite high if they put strenous pressure on their knees. I hope when I grow older, new methods of knee replacements will be available such as the metal foam. Walking and running without pain is taken for granted as a younger person, and I hope I can continue physical activity when I grow older.

CyberKnife for Prostate Cancer

Prostate cancer remains the second leading cause of cancer death in United States, right after lung cancer. While it affects a lot of people, mostly adult over fifty, there are many form of treatment for prostate cancer. One of which is through radiation therapy which have been used for decades by using ionizing radiation sources to kill malignant cell. More progressive form of prostate cancer is requiring higher dose of radiation for intermediate and high-risk prostate cancer patients. Unfortunately, increasing the dose also increases the risk of radiation poisoning.

Thus, the cyberknife is ideal to be use as a cure for cancer. It is quick, accurate, no side effect, and maneuverable for inoperable target. Each therapy take about 90 minutes, involving no operation and painless. Generally, a total dose of 38 Grey in 5 fractions is given to patient for their prostate cancer. In a tested trial data, it has shown that in the phase two of cyberknifing, there is shrinkage in the prostate tumor by at least 5 mm. Radiation poisoning is relatively low compare to other radiation therapy.

There is two cyberknife methods, heterogeneous and homogeneous planning. Homogeneous planning involve small amount of dosages gradient through the target volume which take 45-50 minutes. Heterogeneous planning uses more beam at higher dosages which take longer, 90 minutes.

I found this article interesting because it is related to my major, Radiological Health engineering. At the same time, this article talks about the physiological aspect. It is dealing with an alternative cure to cancers, radiation therapy, to a rising problem, prostate cancer. Statistical data show us that prostate cancer claims about 28,600 lives each year. Cyberknife might be the next step to curing prostate cancer.


Sources:
http://www.medicalnewstoday.com/articles/200023.php
http://www.tcrt.org///mc_images/category/4309/04-katz_tcrt_9_5.pdf

Sneaking Spies into a Cell’s Nucleus

The ultimate goal is to be able to find the moment when a cell starts to become abnormal causing disease. Duke University has made a major contribution to this effort by discovering a way to slip a spy through a cell wall and into the cell’s nucleus. They completed this task by using silver nanoparticles that are coated with a small portion of HIV protein. The components of the spy are chosen very carefully. The silver nanoparticles are chosen because they are not rejected by the body and they are very reflective of light. The HIV protein is used so that the spy can easily enter the cell and its nucleus, but only a small amount so that no damage is done in the process. Once the nanoparticle is in the nucleus, we can observe the effects that different chemicals can have within the nucleus. An old technique called surface-enhanced Raman scattering (SERS) can be used to test if the nanoparticles have successfully entered the nucleus of the cell. The Raman scatter occurs when the target molecule receives light and returns with its own unique light. The Raman response is enhanced when it is paired with a metal nanoparticle. With this step, they hope to be able to detect early stages in disease, such as cancer, so they can find a way to put treatment into the nanoparticle and prevent the disease from the start.

I found this article interesting because it is a step in the direction towards finding a cure for cancer. I have many friends that have suffered from cancer, and this article gives me hope that someday this will be a preventable disease.

http://www.sciencedaily.com/releases/2010/09/100928111237.htm

The Watchman Procedure: Preventing Stroke in Patients With Atrial Fibrillation

Atrial fibrillation is a disease in which the upper two chambers of the heart quiver instead of their normal beating pattern leading to an irregular pulse and blood flow. This is also the most common form of cardiac arrhythmia, which is a leading cause of stroke. Current medications for this problem include blood thinning drugs such as Coumadin in which the heart rate is slowed and brought back to normal. This however, is a dangerous accommodation and must be monitored closely. One new breakthrough, however, in biomedical engineering is a process known as the watchman procedure. This method is a surgical implant at the top of the left atrium that essentially filters the blood of the patient so that the blood will not clot there. The implant is an umbrella type device that is inserted through the groin, and is similar to the angioplasty procedure. It is noted that this new biomedical implant works better than prescription drugs in patients near sixty percent of the time.

This new biomedical breakthrough is important in ways beyond the health and safety of preventing strokes in people who suffer from Atrial Fibrillation. This implant is in essence competing with pharmaceutical companies that produce blood thinning drugs for patients with this arrhythmia. I found this to be interesting because in most cases one would not expect for these to be competitive sectors, but rather cooperative groups. In most biomedical procedures, medications are also necessary in respect to the device being implanted so that they work together to complete a task. In this case however, the watchman procedure would replace the Coumadin in these patients, and also decrease their risk of stroke at a higher rate than the medication.

http://www.sciencedaily.com/videos/2005/1203-stopping_strokes.htm

Research reveals new options for people with phenylketonuria

For people with the genetic condition known as phenylketonuria (PKU), diet is a constant struggle.

They can eat virtually no protein, and instead get their daily dose of this key macronutrient by drinking a bitter-tasting formula of amino acids. Yet drink it they must; deviating from this strict dietary regimen puts them at risk of developing permanent neurological damage.

In the near future, fortunately, a better option may become available.

In April, a team of University of Wisconsin-Madison researchers will publish the second of two key papers showing that a unique protein derived from whey - known as glycomacropeptide, or GMP - is safe for people with PKU to eat. GMP is the first known natural protein that is safe for this group, and these findings are poised to revolutionize the PKU diet. Already, Cambrooke Foods, a Massachusetts company that specializes in the manufacture of medical foods, is in the process of developing GMP-fortified snack foods for commercial sale.

"It's so important to individuals on the PKU diet to have new options, to have their diet liberalized. It's a quality-of-life issue," says Denise Ney, a professor of nutritional sciences who led the two studies. "Adolescents have an especially difficult time [staying on the diet], but it's so critical that they do."

People with PKU are born without the enzyme responsible for breaking down phenylalanine, one of the 20 major amino acids that form the proteins we eat in everyday foods. While small amounts of phenylalanine are essential for PKU patients, excess amounts stay in their bodies indefinitely and interfere with brain function. Those who go off-diet often suffer from concentration problems and depression. Some even sustain permanent brain damage. The GMP protein isolated from whey, on the other hand, is the only known dietary protein that contains only trace amounts of phenylalanine; absolutely pure GMP, in fact, is completely phenylalanine-free.

The first GMP human feeding trial was published in February in the Journal of Inherited Metabolic Disorders. In it, Ney and her team describe the experience of an individual with PKU who volunteered to consume an all-GMP diet for 10 weeks. As the paper explains, not only did the subject enjoy the GMP-fortified snack bar, pudding and sports beverage that supplied most of his daily protein, but the amount of phenylalanine in his blood actually starting going down after he ate these items for a couple of weeks.

"And because the subject enjoyed the GMP foods, he was more inclined to eat them throughout the day, which helps keep the body's protein metabolism running efficiently all day long," says Ney. "When he went back to the amino acid formula, he went back to drinking it all in one sitting."

Ney's new study, published in the April issue of the American Journal of Clinical Nutrition and appearing online on Feb. 25, describes an 11-person trial of shorter duration involving PKU patients receiving care from UW-Madison's Waisman Center who agreed to spend six days at the University Hospital's Clinical and Translational Research Core. In the study, subjects adhered to the amino acid formula diet for four days, and then switched to the GMP diet for the following four. (Subjects spent the first two days of the study at home.) In the end, no adverse health problems were found, and 10 of 11 subjects claimed to prefer the GMP diet, making the bottom line of this study the same as the first - that GMP is safe and acceptable.

In this shorter study, variations were seen among individual subjects, but the overall blood phenylalanine levels measured after meals were comparable in the two diets. Additionally, the GMP diet improved protein metabolism compared to the amino acid formula.

Members of the PKU community have been eagerly monitoring the progress of this research project for nearly a decade, since UW-Madison food engineer Mark Etzel published a key paper describing how to isolate GMP from whey. A few years ago, when things got to the point of starting human feeding trials, the researchers discovered they already had a long list of eager volunteers, including Matt Cortright of Wausau, Wisconsin, who developed seizures and other problems after abandoning the amino acid formula for a few years during early adulthood.

"The main reason I helped out with this study was so that newer generations won't have to go through the things I have. It makes me happy to see how far the studies have come since I was younger, and the choices future generations will have," writes Cortright, now 32, in a letter to Ney. "I just hope that I will also have the opportunity to use these [GMP food] products [in my own daily life] as well."

http://www.news-medical.net/news/2009/03/30/47672.aspx

I thought this article was extremely interesting because it applies to me directly. I was diagnosed with PKU (phenylketonuria) when I was about 2 weeks old, and while it is something that I am used to after living with the disease for 20 years, I am always looking for news and updates about new treatments and research they are coming out with to improve the lives of PKU patients/possible progression towards a cure. While I had heard about the new breakthrough with the whey protein GMP, I hadn’t read anything about the actual clinical trials they performed or that medical foods made with GMP got such good reviews from the people who participated in the clinical trials. I will definitely be on the lookout for new foods/formulas made with GMP!

Identical Twins Identical Problems

While this article is a few years old, I found it fascinating that researchers are using identical twins in the study and research of the development of diseases, in this case rheumatoid arthritis. Rheumatoid arthritis affects around 2 million Americans and is a chronic inflammatory disease that affects joints. This genetic disease limits mobility and movement, causes extreme pain and bone deformities, by destructing joints. Rheumatoid arthritis forms in the beginning when the joint tissue grows and subsequently divides similar to how a benign tumor forms. This mass then releases proteins that harm tissue. The only treatments available for this type of arthritis do not cure the underlying problem, they only help other processes, and these treatments are not inclusive in that they don’t help every patient.

The way the researchers are using identical twins is very innovative. The special thing about identical twins is that they have the exact same genetic code. This is quite a benefit because any variation in the gene can be accredited to a person’s surroundings. The variations in an individual’s surroundings could influence how DNA is packed or could cause an accidental genetic mutation. In the twins they studied, the twin with rheumatoid arthritis had three overactive genes compared to the twin without RA. Through this study researchers were also able to identify that genes would be different if neither twin had RA compared to if a different set of twins had it.

These researchers also are open to the idea that the specific genes are prone to oxidative stress. This changes how the individual cell will fix itself in a gene, getting back to how RA forms. This will not always stress the disease to start, but when it does it is the reason why only one twin will get RA.

Studying these twins have helped the researchers to better comprehend RA and recognize new targets for drug treatments, and hopefully they will be able to create drug s that help more people, target the disease better, and have less harmful side effects.

This article caught my attention because I’m a twin. Although I am not an identical twin, I am still interested in the gene research and fascinated that the researchers can study and use the identical genes that identical twins have as a basis for finding the root cause of diseases and hopefully manufacturing new and better drugs for a cure.

http://www.sciencedaily.com/videos/2007/0711-identical_twins_identical_problems.htm

"Researchers create first molecule able to block key component of cancer genes' on-off switch"

A group of researchers created a molecule called JQ1 that blocks an abnormal protein seen in a form of cancer known as NUT midline carcinoma (NMC). NMC is a rare, normally fatal cancer that affects children and young adults. It is caused when two genes from different chromosomes attach to each other and cause the cell to create an abnormal protein called BRD4-NUT. The molecule JQ1 that was created acts as an inhibitor for a reader protein of the BRD4-NUT gene. The researchers successfully tested JQ1 by transplanting NMC cells into mice and then giving some of the mice the JQ1 molecule. The mice that received the NMC cells and the JQ1 molecule survived while the mice that were only given the NMC cells died.

I found this article interesting because I am very interested in cancer research. Cancer is a leading cause of death throughout the world and research like this gets us one step closer to having a cure.

http://www.dana-farber.org/abo/news/press/2010/researchers-create-first-molecule-able-to-block-key-component-of-cancer-genes-on-off-switch.html

Implantable Blood Glucose Biosensor

I'm sure most of us are familiar with diabetes (diabetes mellitus). Just in case, its the constant high glucose level in the blood. Its caused by either the inability to produce the right amount insulin, or cells' lack of response to insulin. High glucose levels in the blood can cause complications in the eyes, heart, brain, kidneys, brain and feet. Because of this people with diabetes must regularly check their blood glucose level.

Traditionally diabetics prick their finger in order to draw blood, and the blood sample is tested using a glucose meter. More recently a new technique was used where a needle-sized sensor is put deep into the skin and wirelessly provided blood glucose monitoring using small pager-sized monitor. However the problem with this sensor is that the human body would surround the sensor with scar tissue. This of course makes the sensor ineffective and has to be replaced every 3-7 days.

However scientists at the University of California at San Diego and biotech company GlySens have developed an implantable sensor that provides constant blood glucose levels to a wirelessly, much like the previous device. But it can remain implanted for over 500 days without being affected by scar tissue. The device is 1.5 inches in diameter and half an inch thick (about the size of an oreo) and would be implanted in a person's torso. The device has two sensors (one which detects oxygen and the other reactions involving oxygen and glucose). Glucose levels can be sent to a cell phone, so no other external monitoring equipment is necessary. The device has been successfully tested on animals but not humans yet.

I found this article of interest because both my grandmother and my uncle have diabetes. My grandmother has actually lost most of her sight because of it. And of course diabetes is common, affecting 16 million people America and another 2.6 million people in the UK. Devices like these will make diabetics everyday lives just that much easier.

http://www.biomedicalblog.com/implantable-biosensor-to-measure-blood-glucose-continuously/19500/

Composite Materials in Medical Technology

Bioengineers looking for higher-performance materials to make their medical devices out of have turned to their fellow aerospace engineers for some assistance. In the aerospace industry the cutting-edge material to design aircraft with are composite materials like carbon fiber. The composites are lightweight materials known for their strength and stiffness. The characteristics of these composites are the same desired properties for medical purposes, things like orthopedic devices, implants and surgical instruments.

Consisting of organic polymers infused with fibers made from carbon or glass to add strength, these devices have attributes far out performing conventional metallic alloys used in orthopedic procedures. For instance metallic alloys tend to be very dense while the composites are extremely light yet out perform the metals in their tensile strength. Another important feature concerning medical devices implanted in the body is corrosion. Because of the organic materials in these composites, they are extremely resistant to corrosion, which means that the device will not break down or weaken while in the body. Along with these two aspects, composites have a host of other exceptionally beneficial characteristics. One such characteristic is the hypoallergenic properties of composites. Because these materials are not made form metallic alloys there is no chance that metal ions could be absorbed into the tissue and cause allergic reactions. Another highly favorable quality of these materials is in the design aspects. Devices made from composites can be customized to match the exact mechanical properties of the bone and joint system they are attached to, allowing for the bone to remain strong and not be broken down by the body due to a lack of mechanical loading. Finally these new materials are extremely helpful to doctors because x-rays can penetrate them, or at least to the same degree of most tissues, allowing doctors to more accurately interpret the images. It is easy to see why some many doctors and bioengineers are interested in designing new devices and tools from these materials; the one hurdle they must overcome is the price.

The relative cost of devices made from composite materials is much higher than conventional materials. It seems that making the materials is where all the money goes, rather than in the case of metallic alloys where the main cost is in the device’s design and inspection. Some engineers believe that given more time to let these materials take over a larger chunk of the market, the whole production process will become more cost efficient by assembly line automation.

I found the article very intriguing because I’ve seen the use of composites like carbon fiber in high performance machines, like aircraft and Formula 1 racecars before and thought how naturally it could make for very strong and light prosthetic devices. Although this article didn’t talk about the use of the composites in prosthesis and the may be a ways off, but I definitely anticipate the arrival. This is a great step to the direction of better longer lasting orthopedic devices that I hope to be apart of designing.

Source: http://www.emdt.co.uk/article/aerospace-inner-space-composite-materials-medical-technology