Thursday, March 31, 2011
Sick Gorillas?
These illnesses are potentially fatal to these gorillas, and has already killed several including two infants. These symptoms these gorillas have are, coughing, eye and nose discharge, and lethargy. Pneumonia and human metapneumovirus (HMPV) are the two leading respiratory infections found in these gorillas. If these creatures become extinct, we the tree of life loses a species that has 98% similar DNA to humans.
Link http://www.biologynews.net/archives/2011/03/29/human_virus_linked_to_deaths_of_endangered_mountain_gorillas.html
-Phillip Hunt
Wednesday, March 30, 2011
MAYBE IT'S BETTER FOR SOME INSECTS TO STAY QUIET
I am sure many of you have experienced the sound pollution produced by cicadas during the late spring and summer months. The tymbal, which is the sound producing organ in male cicadas unintentionally attracts Sarcophagid parasitoid flies. The fly oviposits a single egg in its cicada host that subsequently develops into a larva that is capable of destroying the tymbal. By destroying the tymbal, the fly larva reduces future host competition at the expense of the cicada, which loses the ability to attract females, and eventually dies when the larva emerges.
In the case of an introduced Australian cricket to Hawaii, chirping in males has been reduced because it attracts a nocturnal tachinid fly parasitoid (Ormia). Selective pressure by the parasitoid fly has favored a wing mutation in the crickets that prevents their ability to chirp and attract females. However, it is thought that males with the wing mutation may begin to behave like satellites of regular males that are capable of chirping and attracting females, so they could increase their reproductive success.
Posted by: Nelson Milano (2)
Breakthrough in the Study of Aging
An interesting discovery has been made by the Buck Institute for Research on Aging in California. They have been using a common yellow dye called Thioflavin T or ThT as a treatment for worms that bred to show similar symptoms of a person with Alzheimer's. This dye not only slowed down the progression of the Alzheimer's in the worms, it also extended the lifespan of healthy worms by 50%.
Gordon Lithgow the director of this study wants to use other compounds to stabilize protein homeostasis. Protein homeostasis is the ability of an organism to keep the balance of proteins. The ThT binds the amyloid protein fragments which are associated with Alzheimer's disease. The ThT works in slowing the progression of Alzheimer's disease in the worms by decreasing the speed of the clumping of the amyloid protein fragments. In addition to these findings Lithgow has said that the ThT could potentially if studies continue to be successful, prolong the lifespan of healthy humans as well.
Silvestre Alavez another scientist working on the Lithgow research team has also discovered that curcumin an ingredient in the spice tumeric also has similar health benefits of the ThT.
The discoveries made by the Lithgow research lab are major in the study of aging. This study will continue on more complex animals such as mice.
Posted by Jessica Kusmirek (2)
Brain Damage Being Linked To Obesity
There are plenty of well known reasons as to why being overweight or obese is unhealthy: type 2 diabetes, heart disease, high blood pressure, stroke and the list goes on. But what some people probably aren’t aware of is the potential damage being overweight can have on an unlikely part of your body--your brain. A report in Science News discusses a study which has been done comparing memory, thinking, and reasoning abilities in those suffering from obesity before and after substantial weight loss. Perhaps what is even more interesting than the fact that obesity can diminish such abilities is that the damage has been shown to be reversible with weight loss.
This study, which was conducted at Kent State University, involved one hundred and fifty obese subjects. When tested on their cognitive abilities, the individuals generally performed with lower than average results when compared to healthy people based on data from the Brain Resource International Database. Two-thirds of this study’s subjects went on to take measures, including bariatric surgery, to lose approximately fifty pounds. Though still overweight (the average individual being tested originally weighed in at just less than three-hundred pounds), the lighter patients were reassessed. These patients showed a substantial increase in their scores, most of them scoring in the average or even above-average range. On the other hand, test subjects who did not go on to lose weight showed a decrease in their scores, a surprising result to the researchers. Neurologist Stefan Knecht quotes, “You can actually watch them getting worse from one three-month period to the next if you have sufficiently sensitive measures, which [they] did.”
This is not the first time brain function in relation to being overweight has been observed. An article in The New York times describes studies done in both California and Sweden that have shown that people in their forties who were overweight were more prone to dementia over the next several decades in their lives. One suggested reasoning for this is the hormone like leptin (which is thought to play a role in the development of Alzheimer’s) which is secreted by fat tissue. Another hypothesis is that other secretions by fat tissue cause chronic inflammation of the brain, impairing one’s learning and memory functions.
A study done by previous mentioned neurologist Stefan Knecht at theUniversity of Münster in Germany used magnetic resonance imaging (MRI) to show a linkage between C-reactive protein, a blood marker of systemic inflammation and white matter (a protective layer that insulates nerve cells in the brain) integrity. His findings showed that higher levels of CRP correlated with worse performance in areas such as speed and attention, otherwise known as “executive functions.”
If the risk of heart disease of diabetes is not enough to motivate overweight individuals to strap on a pair of walking shoes and start cutting down portions sizes, then perhaps knowing that their intellectual abilities are on the line will serve as the final push towards a reformed lifestyle.
Posted by Brianna Lee (2)
Cosmology’s Inflation Debate: Why the Big Bang Theory may be Flawed
Paul J. Steinhardt explains in his “The Inflation Debate: Is the theory at the heart of modern cosmology deeply flawed?” from the April, 2011 issue of Scientific Americans that indeed, the universe may not have rapidly expanded following the big bang. This rapid expansion is termed cosmic inflation, and many have, until now, thought of it as a fact, not a theory. However, this theory is now under great debate. The cosmic inflation theory argues that the shape and consistency of our universe are both the result of a rapid expansion of space immediately after the big bang.
The reason for this debate is that the circumstances for which inflation can occur are very unlikely. In a sense, that is what makes this theory so interesting, and people generally like interesting things. Some scientists may have gone along with this idea because they felt that such an amazing phenomenon as the big bang required an unbelievable explanation to explain it. Another piece of the cosmic inflation theory that is being put under the microscope is how it is believed to be never ending, with no certain endpoint, having no real forecasts as to what the universe will look like in, say, a hundred years.
Scientists all over the globe are currently working to solve whether this mutinous idea that the cosmic inflation theory is rubbish actually has some truth to it. There are many different proposals in the works that deal with either fixing or replacing this inflation theory. It will surely be interesting to see what these scientists come up with as the new working theory to explain the events following the big bang.
Amyloid Beta Plaques, Characteristic of Alzheimer's Disease, Develop in Patients Well Before Symptoms
Dark Chocolate: Good and Healthy
A recent study at the University of Reading supports the notion that dark chocolate may temporarily improve visual and cognitive functions. For up to two hours after consumption, participants in the study had enhanced ability to see under difficult conditions, also known as contrast sensitivity. Researchers used a control group of people who consumed white chocolate as a comparison. Researchers performed the visual part of the study by having participants read a set of numbers on a screen and then lowering the contrast of that screen until the participants could no longer identify the number on the screen. Other visual tests involved the use of moving dots. The dark chocolate group was about 17% better at discerning objects in lower lighting conditions. They were able to read numbers at lower contrast levels than those who at white chocolate. The cognitive tests consisted of memory and reaction time tests. For memory, the participants had to identify objects that changed position when viewing a scene on two different screens. Again, the dark chocolate group outperformed the other and was able to identify more objects that changed location. For reaction time, the participants had to press a specific key based on what was presented on a screen. People who ate the dark chocolate had faster key times than those who ate the white chocolate.
What is the cause of this interesting phenomena? Researchers believe that it is an abundant plant compound, known as a flavanoid, that is found within cocoa beans, grapes, and some tea leaves. Some believe that these flavanoids act as antioxidants or increase the nitric oxide gas production, which helps control blood flow and pressure. Unfortunately, there hasn't been too much research into the health benefits of chocolate. Other studies support the idea that eating chocolate can improve cognitive functions, but researchers still do not know the exact cause of this. More time and research could provide answers to the health benefits and costs of chocolate. Either way, I still plan on adding a little more chocolate to my diet.
Article can be found here
Posted by Kevin McLaughlin (2)
Tuesday, March 29, 2011
Cellular Models Create "Impossible" Standard of Beauty for Most Young Girls
Indeed, a useful tool for studying/ predicting disease and illness would be a means by which researchers could estimate and anticipate the patterns of the behavior of cells involved. Douglas Lauffenburger, head of the Biological Engineering program at MIT, mentioned in an article for Physorg.com that a sound understanding of any disease is reliant on understanding how it effects an entire system. What researchers from MIT and Massachusetts General Hospital have managed to achieve with these new developments is the opportunity to observe different types of cells within the context of an organism's internal machinery. For example, according to Physorg.com, researchers for MIT and MASS General were able to create a computational model for the effect of a tumor necrosis factor's effect on mouse intestinal cells. In effect, scientists were able to more closely moniter where and how a drug was influencing a mouses inner-workings.
The possibilities that can stem from these developments ranges from the testing of new drugs to the study of cancer growth and development. For instance, the growth of cancers functions under an extremely complicated mechanism by which several different signals and signalling pathways are disrupted. A more developed, and specific knowledge of the way in which cancer spreads would benefit the manner in which researchers develop drugs, and would in theory help develop drugs designed around the specific mechanisms of cancer growth.
Currently, the majority of cancer prevention and treatment centers around early detection, and in some cases, surgical removal of cancer cells. With drugs that could prevent that could prevent and eliminate cancer events where our own immune systems fail, it would be possible to reduce the need for surgical and radiation-based treatments.
In effect, without intimate knowledge of how drugs and diseases interact with cells on a systematic level, complicated treatments like that of cancer treatment would be comparable to having to write a blog post when you keep forgetting when your group is supposed to post.
Get Your Cancer Vaccine!
Every year we are bombarded with reminders to get the flu vaccine. But what about a cancer vaccine? Could we actually get rid of the idea of curing existing cancers and simply prevent them from happinging? Scientists are currently working on this idea that targets two types of cancers. One of these types is cancers that are caused by infections. So far there has been some major success in this area. If the infection can be prevented, the resulting cancer can also be prevented. This is the case for HPV (Human papillomavirus) and the two FDA approved drugs Guardasil and Cervarix that have huge success in preventing strains of HPV that cause the majority of cervical cancer. There is still further work being done to prevent all strains of HPV, which could potentially eliminate cervical cancer as a result of this infection.
The other type of cancer, however, cannot be prevented as easily. These cancers, such as lung and colon cancer, are those that are not caused by an infection. To make a vaccine for such cancers, the same principles of the flu vaccine are used: teach the immune system to recognize the antigens displayed by the virus/cancer. In the case of cancers, certain proteins are specific to cancerous cells and can therefore be isolated and made into a potential vaccine that will train the immune system to be better protected against cells that display these proteins. This was successfully shown in an experiment with mice and breast cancer. A protein normally expressed during lactation was also found in breast-cancer cells, which were expressing this protein inappropriately. Mice that were vaccinated against this protein showed 100% protection against breast cancer. It is important to note that this vaccine must be administered before the growth of any tumor cells. While there was damage seen to breast tissue that would cause for concern for new mothers, the age at which 95% of breast cancer begins to appear is around 40, which is typically past the point of breast-feeding. This study seems very promising for the future of cancer prevention and the possibility of making a broad-spectrum vaccine against proteins expressed by various types of cancers.
A major problem in the progress of these vaccines is human studies and the cost these present. Even if these testing costs are overcome, the resulting vaccines will be extremely expensive and very likely out of the price range of most people. Despite the cost, however, these studies clearly show the progress we are making toward the future of a cancer-free world.
Posted by Marlena Grasso (2)
Monday, March 28, 2011
Another Risk For Breast Cancer
Phthalates are the new source that is putting these women at risk of developing breast cancer. Phthalates are oils that are used to finish products giving them longevity for usage. The most common usage is in nail polish, perfume, tools, adhesives, paint colors, and etc. This oils can be used in almost anything that is made to last or be durable. Because of its popular use, it does not seem far-fetched that it would cause environmental health issued. As far as public health is concerned this substance is safe to use and not harmful in any way to humans or to the environment because it is biodegradable.
Researchers in the study to figure out what it was in phthalates that was making these woman susceptible to breast cancer came to find that it was a residues of monoethyl phthalates, which is found in urine. Researchers had considered possible other risk factors but believed that this was a definite. Through an experiment they found that there was correlation between phthalates and breast cancer, especially in woman that were postmenopausal. They measured concentrations in the urine and proved their hypothesis.
So to add on to the list of risk factors for getting breast cancer or a cancer is the new addition of phthalates. The worst part of recognizing this risk is that it is a product that has been used for more than 50 years and is in everyday things that people use. But most ironic is that it is not like the products but being affected by their own excretions does affect these women.
-Jean Fedna
http://www.environmentalhealthnews.org/ehs/newscience/exposure-to phthalates-higher-breast-cancer-risk/
Thursday, March 24, 2011
Serotonin keeps Mice Straight
There is still a lot not known about this study. For example it is still not know how female mice would be effected if they were to lack serotonin. Also not known is how this would effect human beings. But if serotonin is a neurotransmitter, which effects human emotions, and is said to make people feel better, could taking away serotonin producing brain cells make someone almost, for lack of a better term, crazy?
http://www.sciencenews.org/view/generic/id/71586/title/Brain_chemical_influences_sexual_preference_in_mice
Wednesday, March 23, 2011
Mosquitos
Like many things, this hypothetical really depends on where you are looking at. The importance of mosquitoes varies from ecosystem to ecosystem, something that is fairly intuitive. One prime example provided in the article is that of the Arctic tundra. In the Arctic, mosquitoes have an annual hatching where there are massive numbers of adults for a short span of time. These mosquito swarms not only act as a food base for many birds and fish, but also they have a direct effect of the paths that caribou take on their migrations, in order to avoid these choking swarms of bloodsuckers. The removal of these mosquitoes may serve to devastate the stability of the Arctic tundra biome.
However, there aren't especially many people for mosquitoes to annoy up in the Arctic tundras, suppose that we eradicated them in a less far-removed location. What would be the consequences of that? Studies showed that many species rely on mosquitoes as a food base. This ranged from spiders, fish, other insects, and many birds that simply had a diet of which mosquitoes are fraction to very specialized predators like the mosquitofish, which (as the name implies) is a predator that predates almost exclusively on mosquitoes. An experiment done with house martins revealed that the birds averaged one more egg per nesting in areas where mosquitoes were present. However, other species such as bats have a very small gut content of mosquitoes and would not be disturbed by their removal. Many ecologists speculated that the mosquitoes were filling an easily replaceable niche that would not be particularly crippling in the larger picture when they were removed. Mosquito larvae also have a notable role in the environments they inhabit. They help decompose decaying organic matter back into nutrients which are released back into the environment. However, they are just one among many species that perform this task, and in most areas don't make up an abundant amount of the biodiversity. It is only in, again, very specific areas and ecosystems that the removal of mosquitoes would be felt with some significant gravity.
This is just the ecological part of the picture. What sort of humanitarian reasons could we have for exterminating a species entirely beyond that they are just plain annoying? Mosquitoes are what is referred to as disease vectors, that is, mosquitoes spread diseases through sucking one organisms blood then depositing in their next meal. This transfer of bodily fluids spreads all sorts of nasty contagions. Mosquitoes spread malaria, which is one of the leading causes in death in many underdeveloped countries. It claims approximately one million a year, and infects 247 million. Other diseases born on the wings of mosquitoes are dengue fever, yellow fever, Japanese encephalitis, Rift Valley fever, Chikungunya virus, and West Nile virus. Exterminating mosquitoes could potentially cripple the virulence of these diseases and save millions of lives each year, not to mention extortionate amounts of money in the department of healthcare and disease prevention. The drawback for this, of course, is having more people alive in a world that is already considered to be over carrying capacity. But it is something of a tough call to make by saying that the issue of overcrowding is worse than the horrific effects that these mosquito-borne diseases have on the world. In that respect, the article concludes with the statement that it is probably our limitations on the ability to exterminate these pesky bugs that stops us from doing so more than the dilemma of whether it will have devastating effects on the world that stops us from getting rid of mosquitoes all together.
LINK: http://www.nature.com/news/2010/100721/full/466432a.html
Agriculture going green?
Harvard's Cell `Makeover' May Spur Diabetes Therapy
Using biological alchemy, Harvard University researchers turned one type of cell found in the pancreas of mice into the variety that secretes the hormone insulin.
If the technique can be used safely in humans, one day it can treat diabetes, which occurs when the body either can't produce, or else makes too little of, the insulin needed to process blood sugar. The same approach might be used to make heart, brain, or liver cells from other existing cells and treat diseases in those organs, said a stem-cell scientist who wasn't involved in the findings.
The research team in Cambridge, Massachusetts. The scientists injected viruses bearing three genes into the mice, transforming a common pancreatic cell known as an exocrine cell into the much rarer beta cell that makes insulin. Their findings were published in the journal Nature.
Melton said he aims to refine the technique, show that it can be done safely, and begin human clinical trials within two to five years in diabetes patients.
``We were able to flip the cell from one state into another, what one of the younger students in my lab calls an extreme makeover,'' Melton said yesterday in a conference call with reporters.
The Harvard researchers are calling the process direct reprogramming.
The research says that every cell in a person or animal contains DNA with the complete set of genetic instructions required to create that individual. By turning select genes on and off, scientists can transform existing cells so they start looking and acting like others.
Melton and his team spent three years searching for so- called transcription factors, which control proteins that in turn switch other genes on and off. They started with 1,100 candidate genes and narrowed the field to 28 that are involved in forming the part of the pancreas where beta cells are found.
Finally, they settled on nine genes they guessed might be involved and began a trial-and-error process, injecting them into the pancreases of mice and eliminating one at a time. Finally, they found that just three genes were needed and that 20 percent of the exocrine cells they injected turned into beta cells.
Cleopatra Duque
Friday, March 11, 2011
Relationship of Sleep Apnea with Snoring
Snoring is something that you really want to get rid off from your life. Snoring is also sometimes associated with embarrassment and also plays an important role in spoiling sleep of others who are around you. Many scientists and researchers working closely to identify the relationship of snoring with other sleeping disorders, and discover that the most related disorder with snoring is Sleep Apnea.
Wednesday, March 9, 2011
Being Bigger is Better and Faster
The researches working at the National Evolutionary Synthesis Center conducted a study where they reviewed the national selections of hundreds of species of birds, lizards, snakes, insects and plants. They found that the larger body size and earlier seasonal timing including breeding, blooming or hatching have a larger effect in their survival.
However, the puzzling part is that why the concept of “bigger is better” is so common in evolution study. The authors studied “Goldilocks” model known as stabilizing selection, where they argued the idea of having rare cases of being intermediate size that survive and reproduce better. For example, human birth weight: newborns of intermediate size are more likely to survive than newborns that are extremely large or small, but it is rare case. The reasons for why it’s so puzzling concept is because most creatures are well adapted to the environment in which they live.
The authors presented three possible explanations for this puzzling concept. One possibility is that evolving to be bigger and faster comes at cost meaning there can be a trade off between their survivals and reproducing. Another possibility is that the environments changes from seasons to seasons, in which the trait that has greater advantage changes over time such as in Darwin’s finches’ example, where large-beaked and small-beaked birds were favored due to availability of seeds. The third possibility is that natural selection drives one trait in one direction. For example, it can be advantage for flying insects to evolve larger wings and smaller bodies for more efficient flight; however, insects with larger wings having larger bodies cannot evolve.
From these explanations, the authors concluded that the third explanation limits the evolution of body size. However, the traits related to timing and/or body shape does not correlate with the idea of “Goldilocks” model.
Posted by Arpita Patel
The Medical Benefits of Caffeinated Coffee
A recent study by Gavrieli et al. in the Journal of Nutrition demonstrated that caffeinated coffee intake is directly correlated to weight loss, with habitual coffee drinkers consuming 21.7% less food than those using a decaf placebo. On a wider chemical front, cortisol—the molecule involved in bone-marrow production—concentration falls less in men drinking coffee than those who are not. This study compliments a separate longitudinal study currently underway to investigate why habitual, coffee drinking men are less likely to develop prostate cancer. A myraid of other studies have found zero correlation between coffee drinking and heart disease, kidney stones, cancer or other diseases allegedly resulting from coffee consumption. That said, coffee plays a much larger role in public health than most of us tend to think.
Six years prior to Gavreili's article, a major review of longitudinal and cross-sectional studies in world-wide, habitual coffee consumption from JAMA made a fascinating discovery: regular coffee drinkers who consume 6 to 7 coffee cups per day have a 28% lower risk of developing type 2 diabetes, while those who drank 7 or more cups lowered their risk by a staggering 35%. These findings should not be taken lightly. According to the World Health Organization (WHO,) over 90% of the 220 million people diagnosed with diabetes are type 2. Sadly, 80% of the net diabetes mortality rate is from lower-income and developing countries without access to basic medical infrastructure. Most disturbing; however, is the projected mortality rate, which is expected to increase by 200% over the next 20 years. If something as prevalent, innocuous and inexpensive as coffee can decrease the risk by 35%, those involved in health policy and diabetes research should be examining effects of coffee very, very closely.
While the positive effects of coffee are well known—and the quackery surrounding the negatives dismissed—many researchers are still in the dark as to the actual mechanisms by which coffee benefits our health. Proposed candidate mechanisms abound, to include chlorogenic-acid induced pathways, which may reduce glucose output via inhibition of glucose-6-phosphate; Glucagen peptide-1 pathways; protein-3 induction; effects of magnesium in coffee and many, many more. Labs, hospitals and health organizations will likely spend years learning more about the mechanisms and long term benefits of the world's most popular beverage. Either way, it's nice to know that, at the very least, the average cup of coffee does a lot more than just wake us up in the morning.
I'll Have Some Diamonds With My Chemotherapy
The development of chemotherapy has been a revelation since cancer has been a diagnosis, being successful as treatment for a majority of cancers. However, some cancers have a resistance to drugs and do not respond to treatments like chemotherapy. A new method of attacking the drug resistant tumors is by adding nanodiamonds to the chemotherapy.
Dean Ho is a biomedical engineer at Northwestern who has recently been adding flakes of diamonds to chemotherapy and administering to mice with drug resistance cancers. Since diamonds are only carbon, it is nontoxic and seemingly makes the drug less toxic to the host. The results thus far have shown that the chemotherapy can stay in the system up to ten times longer. The importance of this is that the drugs have more time to act upon the tumor, which seems to be related as tumor sizes have significantly decreased.
These trials are still in early development, but with such promising results Ho is planning to continue in larger animals such as rabbits. A concern is that there may not be an advantage over other drug carriers such as gold or silica that are currently being tested as well. Perhaps with more testing of natural, unlikely substances, there is potential for more effective drug carriers.
Thursday, March 3, 2011
New connection in cancer treatment.
Researchers have made an interesting find in the area of cancer research recently. Two different studies each independently provided a link between the FBW7 gene and a resistance to treatment with chemotherapy drugs that focus on tubulin to kill cancerous cells, such as Taxol. Tubulin is a protein which is integral in the network of filaments that maintains the cells infrastructure. Cells which are affected by anti-tubulin drugs cannot divide and eventually die without causing further spread of cancerous cell lines. However, many cells display a resistance to the affects of the anti-tubulin drugs. Which prompted some researchers to ask 'why?'.
One of the research projects that made the connection to FBW7 and this resistance was lead by Ingrid Wertz, this was prompted by the observation that some cells resist Taxol treatment. Wertz and her team noticed a trend that cells which had survived treatment had lower levels of MCL1, a protein associated with the cell's life cycle. Further observation revealed FBW7 was found to be destroying MCL1 in these cell, FBW7 was already known to be a cancer-fighting element in cells. Speculation was that defects in FBW7 may result in higher levels of MCL1 which allowed cells to resist treatment by anti-tubulin drugs. Sure enough, researchers soon found the link between these two proteins.
Another project, headed by Wenyi Wei was focused on researching a particular disease: T-cell acute lymphoblastic leukemia. With this disease, cells have a cocktail of proteins that should cause them to self-destruct but do not do so. Researchers looked into why this occurred and found that these cells lacked the FBW7 gene and without this, they did not break down MCL1 which was a necessary step in cell death. Wei connected this to drug resistance when T-ALL cells that were treated with drugs that targeted cell survivability-pathways were found to have lowered levels of MCL1 also. To try to fix this, Wei treated the cells with a drug that lowered MCL1 drugs and restored sensitivity to treatment.
While exciting in the prospect that oncologists now have insight into reasons why patients may be feeling less many experts in the field are quick to note that these results are only preliminary. They provide just a small glimpse at the bigger picture of cancer treatment. Research has shown only one implication of defects in the FBW7 gene, many other details may lie further downstream in the regulation of cell growth and death. But this is surely a good step for better, more effective cancer treatment.
Wednesday, March 2, 2011
THE PLASTIC NATURE OF THE INSECT TRACHEAL SYSTEM
The insect tracheal system is a network air filled tubes that provide the cells and tissues with oxygen, and like the human respiratory system, eliminates carbon dioxide as a product of cellular respiration. The network of tubes branches throughout the insect’s body and connects directly to the muscles and other energy extensive areas. For those who do not know much about insects, they do not breathe through their mouths. Air is inhaled and exhaled through openings in the cuticle called spiracles, which are located on the thorax and abdomen. Thoracic spiracles are involved in inhalation while abdominal spiracles are involved in exhalation.
During the life cycle of insects especially in those that are holometabolous (larva->pupa->adult) the tracheal system faces various challenges. It has to be plastic enough to adapt to different changes in the insect during growth, ranging from a simple posterior to anterior tube as a larva to a highly branched tubular system that is connected to muscles such as ones for flight. To understand these changes, the effects of oxygen deprivation are considered. In the 1950’s Sir Vincent Wigglesworth, a pioneer of insect physiology demonstrated that hypoxia in Rhodnius (kissing bug) mediated the plasticity of the tracheal system. By managing to surgically cut the trachea of certain segments of the kissing bug, he noticed that the tracheal branching from anterior and posterior sections migrated to areas of hypoxia. This experiment was followed by transplanting certain organs that required lots of oxygen to areas of hypoxia, which resulted in a similar response. Thus, these findings demonstrate how insects are capable of coping with environmental variation.
Posted by Nelson Milano (2)
Maxwell’s Atomic Coilgun: The Quest for Absolute Zero
Scientific American’s March 2011 article entitled “Demons, Entropy, and the Quest for Absolute Zero” by Mark G. Raizen reveals just how low of temperatures can now be reached with Maxwell’s Atomic Coilgun and what implications this has in modern science. The second law of thermodynamics deals with entropy, and how natural processes always go toward lower order; entropy is disorder. Maxwell and his atomic coilgun aim to turn that law on its head to realize an idea from the nineteenth century. This idea involved “Maxwell’s demon and appeared to violate the second law of thermodynamics because it could lower the entropy of the gas while expending a negligible amount of energy” (58). A man named Szilard talked Maxwell’s demon out of this paradox in a very complex manner. Just know that it did not violate the second law of thermodynamics.
The way modern scientists go about getting gas atoms and some gas molecules to such low temperatures starts with using a vacuum. They launch this gas into a vacuum at super-high speeds, making temperature decrease drastically. This gets the gas’s temperature to around 1/100 a degree above (barely) absolute zero. Next, these scientists use magnetic brakes called an atomic coilgun to reduce the speed of these atoms/molecules. These atomic coilguns were originally designed to do the opposite, accelerating particles and large projectiles using the same magnetic field. This technology is applied in reverse to slow the particles this time. Most elements have north and south magnetic poles, and all elements that do can be controlled by these atomic coilguns.
That was stage one of cooling; here is step two. At this point, an atomic coilgun would have cooled down atoms/molecules to 1/100 of a degree above absolute zero. Some might say that this is close, but no cigar. Wiser men would realize that this new achievement in science will allow us to discover much about matter that is currently unknown, and possibly not just about matter’s properties, but maybe about antimatter and its properties. This list could go on and on; nobody knows. Anyhow, at stage two of cooling, the temperature is brought down to one-millionth of a degree above absolute zero, or even lower! Here, scientists use a technique called single-photon cooling, which “appears to violate the second law of thermodynamics” (59). This method uses a one-way gate once proposed by Maxwell in 1871 in a thought experiment. This gate compresses atoms down to a smaller volume, all the while without raising their temperature! The gate follows by letting the atoms expand to the initial volume. This, however, lowers their temperature.
This has opened many doors in research. One is to study chemical reactions at a quantum level. Another possibility of utility of this research would be to work to lift the barriers of the current ultrahigh-precision spectroscopy and make it even more precise. Two more would be to measure the mass of a neutrino, and maybe even that of an antineutrino. This applies for antihydrogen as well, which will tell us more about antimatter and its reactions to gravity. One more is to aid in the separation of isotopes. Yet another is to help us better understand how atoms look down to the nanometer. This list may go on forever.
Posted by Derek Melzar (2).
men can also get HPV?
There are many different types of HPV and more than 40 that can be transmitted sexually. vaccines, Merck’s Gardasil and GlaxoSmithKline’s Cervarix, protect against cancer-causing HPV and both vaccines are recommended for young women. Gardasil is also recommended for boys up to age 18 and its protection extends to two additional types of HPV that cause genital warts in males and females.
In 2005, Giuliano of the H. Lee Moffitt Cancer Center & Research Institute and an international team of researchers got together more than 4,000 men living in Brazil, Mexico and Florida into a study of HPV. The average age was 32 and none had been vaccinated against HPV. Swabs of the penis and genital area of each man revealed that 50 percent were infected with at least one HPV type upon enrollment.
The researchers repeated these exams every six months, and the men completed personal-history questionnaires. Over a median of 28 months, the group acquired 1,572 new HPV infections.
The human immune system can clear HPV out of the body, and the men wiped out most of their new infections during the study period. But it took a median 7.5 months. Median clearance times didn’t vary substantially among the countries, but did vary between HPV types. Some cases lingered as long as 24 months in the men.
The data also states that men who reports having 10 or more sexual partners in their lifetimes had roughly twice as many HPV infections as did men who had had one partner.
Giuliano says many insurance programs cover HPV vaccination in boys up to age 18.
“HPV vaccination in men will protect not only them but will also have implications for their sexual partners”
Dwarfism Linked to Cancer and Diabetes Prevention
Who said good things didn’t come out of unfortunate situations? That is certainly not the case for the genetic disorder that is revolutionizing research on cancer and diabetes. Laron syndrome is a fairly rare autosomal recessive disorder, currently affecting about three-hundred people worldwide. Its distinguishing symptom includes insensitivity to growth hormone causing dwarf-like stature. Scientific American has recently introduced Jaime Guevara-Aguirre, an unofficial doctor in Ecuador. He has the unique opportunity there to study the one-third of the world’s population affected by Laron Syndrome who reside in southern Ecuador. His studies on those with Laron Syndrome have led him to make some remarkable observations that could potentially change medicine as we know it: In a community with a 5% diagnosis rate of diabetes and a 17% diagnosis rate of cancer, virtually none of his patients have been diagnosed with either.
Laron’s Syndrome is associated with a mutation in the growth hormone receptor gene (GHR). The individuals also have unusually low levels of insulinlike growth factor 1 (IGF1), which is a hormone that rapid multiplication of cells and inhibits apoptosis. Studies have been done that suggest protection from oxidative damage to DNA by toxins actually comes from a lack of IGF1. Other research has proven that dwarf mice with the same GHR mutation also have decreased rates of cancer, higher protection against diabetes, and even increased life spans. The molecular studies have collaborated with Guevara-Aguirre’s, making the overall research the first time deficiency in GHR has been studied on humans. Growing from research done strictly on lab mice, we can now conclude that IFG1 is undoubtedly an important determining factor of cancer.
There is no doubt these findings will take us to great places. In the near future, doctors may be able to prescribe IGF1-lowering drugs to protect those at risk for cancer and diabetes, similarly to what they would do for those with high levels of cholesterol. Additional research being done on IGF1 and GHR is expected to be done and will hopefully bring us to the day when millions of lives can be spared by a single drug.
Posted by Brianna Lee (2)
Interest in Music has Biological Roots
A recent study has shown that a person’s enthusiasm for music is neurological. At the University of Helsinki a research team studied how a persons neurological makeup affects their interest in music. The team studied 437 people from varying musical backgrounds and age groups. The participants were separated into groups of active listeners and passive listeners. The people in the study were subjected to three tests that measured their musical aptitude and DNA samples were taken.
Researchers have found that there is a connection between sound perception and social communication in humans and other species. This suggests that there is in fact a connection between interest in music and genetics. The participants that were listed as active listeners (frequent concert attendees) tended to have a higher music aptitude regardless of music education.
This particular study is part of a greater project that is studying the biological impact on musical aptitude. This research effort is one of the first of its kind and is still in progress. As an avid music listener I will be very interested to see how it progresses.
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Tuesday, March 1, 2011
PTSD: More Than Psychological
Scientists selected patients who had been exposed to some sort of trauma in their life and found that people with higher levels of PACAP, a receptor for stress signals, were more likely to have PTSD; however, this correlation was only seen in women. They also found a genetic variant to also correspond with PTSD in these patients, but this was also limited to women. This may suggest why PTSD is seen more commonly in women than in men, but does not draw a definite conclusion.
One of the most interesting findings, however, was the effects of childhood maltreatment in patients, both men and women. It was found that in patients who had suffered childhood maltreatment, genes involved in stress response were methylated or suppressed. This methylation changes the gene expression in these patients, making them less able to effectively deal with stressful situations. This not only shows how trauma in childhood can be devastating, but also suggests why PTSD can permanently affect a person’s life.
While these discoveries are certainly eye-opening, they currently have little effect on the treatment of PTSD. The neurological understanding of PTSD is still very limited, and so the results of this study cannot yet be translated into effective treatments. With further research in both the genetic and neurological fields of this disorder, there seems to be a possible brighter future for those unfortunately exposed to horrific events in their lives.
Posted by Marlena Grasso (2)