Monday, February 28, 2011

Injured Cells Getting Killed Before Repair

Based upon current research, scientists believed that most neurodegenerative disease were caused by the accumulation of the aggregates of proteins that cannot be broken down within the brain. These insoluble protein aggregates are deadly to brain cells. Along with that idea, scientists believe that defected pathways that program cell death may effect lead to neurodegenerative disease too. Recent studies at the University of California, San Francisco however have shown that there may be a different factor causing neurodegenerative disease. The apoptic cells - the cells programmed for cell death - in the human brain, according to these studies, are being attacked and cleared out by phagocytic cells of the immune system, which results in a great deal of cell loss over time, thus a neurodegenerative disease such as dementia. Researchers think that these phagocytic cells are attacking the apoptic cells due to a mutation in the gene that codes for progranulin, a protein that plays a role in embryogenesis, inflammation and wound healing. These mutations have commonly been found in individuals who have shown frontotemporal lobar degeneration. In experiments performed upon worms, the worms deficient of progranulin showed decreased numbers of apoptic cells in their lifetimes. This was surprising to researchers at first because they expected to find increased cell death in the progranulin-deficient brains because neurodegenerative diseases seem to stem from brain cell loss; however, the conclusion showed that the problem was not the number of cells undergoing apoptis, but the rate at which the phagocytic cells were removing the apoptic cells. Although this study has not proven that this gene mutation is a cause of neurodegenerative diseases such as dementia, it raises the possibility because it shows scientists that individuals with this gene mutation have cells that are completely removed when injured rather than being fixed like they could be.

The information in the article relates to the real world because brain degenerative diseases such as Alzheimer's and dementia are common topics in the medical world. As scientists grow more aware of what causes brain degeneration, they get closer to finding treatments, cures, etc. This is especially important because these diseases are often genetic and thus, many individuals have concerns that the genes run in their blood and therefore are aware that they potentially might fall to the same fate that they watch their relatives suffer through. Finding medical breakthroughs such as this one might also lead to medical breakthroughs in other fields because it shows scientists looking into different genetic mutations that lack information and finding enlightening results. Along with that, the fact that this gene mutation leaves individuals progranulin deficient gives doctors the possible ability to test for this mutation and tell individuals ahead of time that there is increased potential for them to experience dementia and/or other neurodegenerative disease at some point within their lifespans.

I chose this article because I find the topic of brain diseases and disorders really interesting. My great grandmother passed away due to Alzheimer's and the disease is talked about in current news quite often because it is becoming quite common in the elderly. Thus, I chose this article because it talks about a potential cause of dementia, which has a lot to do with Alzheimer's disease, particularly because it is neurodegenerative. The article is proof that extensive research and experiments are being done in relation to neurodegenerative diseases, which gives hope to society that someday diseases that are very difficult to deal with emotionally, will be cured. The article is important because it lets society know that there is extensive research being performed upon topics such as neurodegenerative diseases, which in turn gives society hope that the medical and science worlds are closer to finding new treatments and cures.

http://www.the-scientist.com/news/display/58031/

Wednesday, February 16, 2011

Stem Cells Can Heal... Or Not?


Recent studies have shown that mutated stem cells may migrate to the surface of wounds in individuals and could potentially cause skin cancer in those people. A skin cancer called Marjolin's ulcer for example, has been connected to many battlefield wounds. Also, 'kangri cancer' has been affiliated with burns that have been caused by heaters worn under clothing in Kashmir. Scientists at the University of California, San Francisco did research and concluded that damaged skin resulting from physical injury may have to do with the migration of mutated stem cells, particularly if the individual with the wound is predisposed to getting cancer. Using mice, scientists looked at basal cell carcinomas, a type of skin cancer said to be a result of a sun-damaged outermost layer of the skin called the epidermis. However, science has shown that basal cell carcinomas are similar to the stem cells that fix wounded skin, thus the skin cancer might be a result of mutated stem cells differentiating in the wound area, causing skin cancer. The researchers mutated a gene in mice that, when done so, has been said to cause skin cancer. Activating the mutated gene within mice did not result in increased numbers of skin cancer in the mice, so the researchers changed the experiment. The mutated gene was again activated in mice, but this time the mice were wounded in one area and sure enough, results showed that the mice developed increased numbers of basal cell carcinoma at the wound site. Some studies have shown that once the stem cells are mutated, they may rest for years without causing cancer and will act once prompted by a wound, but other studies have shown that most basal cell carcinomas do not arise at the site of injury and therefore, the study is not very significant.

This article is very relevant to the world today particularly because media has really emphasized lately the dangers of skin cancer as well as the fact that skin cancer seems to be on a serious rise. Media has stressed the importance of being careful when in direct sunlight, for example on the beach or being out in the daytime during the summer because of ultraviolet rays from the sun. The ultraviolet rays are the reason individuals get sunburned when outside and that particular skin damage has been correlated with skin cancer. Tanning beds have also been been emphasized in the media lately because laying in a tanning booth means laying under direct ultraviolet rays for an extended period of time. Tanning salons have been linked to skin cancer particularly because of the dangers that the increased UV exposure can cause. Individuals sometimes do not know fully the threats of skin cancer and how deadly it can actually be. For instance, melanoma, a type of skin cancer, is extremely aggressive and can kill an individual very quickly. Thus, this article is very much associated with current events today in the world because of the fact that skin cancer is such a new topic with increasing information, research, and studies.

I chose this article because the idea of stem cells interests me and usually when people hear about stem cells, the research or studies being spoken about are related to the medical breakthroughs stem cells are causing or will cause in the future. This article however, looks at stem cells in a different light. The article as said before, links stem cells to skin cancer. Stem cells have been in the media lately because they are undifferentiated cells, which means they can turn into almost all cells within the human body. Therefore, stem cells are capable of differentiating into heart cells or nerve cells, which could fix a failing heart or heal an individual who is paralyzed. The fact that stem cell research is still pretty new to science however leads to questions on whether scientists know the actual long-term effects of stem cell therapy. The studies talked about within this article show that stem cells may actually cause more issues than they fix because if the stem cells are mutated, then when they eventually differentiate, they multiply and create a large amount of mutated cells - in this case, mutated skin cells. Thus, the article is intriguing because it makes the reader wonder whether or not stem cells used in stem cell therapy could have negative long-term effects that currently have gone unnoticed because they have yet to occur in science.

http://www.nature.com/news/2011/110214/full/news.2011.91.html

Sunday, February 13, 2011

Aggressive Squids Fight For Their Women


Researchers discovered that longfin squid become aggressive upon touching recently laid eggs. This information was discovered when calm male longfin squid started attacking each other in the presence of recently laid egg capsules. Female longfin squid lay about twenty to thirty capsules throughout a period of several weeks, each containing one hundred and fifty to two hundred eggs. During this time period, the female squid mate with several different male squid. Scientists began to notice that when the capsules were laid on the ocean floor, the male squid would swim towards them and wrap their arms around the eggs. Finding this behavior unordinary, the scientist team performed an experiment with fifty seven pairs of male squid with egg capsules and observed the actions. Upon touching the capsules during the experiment, the squid went from calm to aggressive and attacking each other within seconds, even in the absence of female squid. In order to determine what exactly was causing this behavior in the male squid, researchers chemically analyzed the surface of the egg capsules and found the several proteins that the surface of the capsules contained. These scientists figured that one of the proteins must be acting as a pheromone, attracting the males to the egg capsules. Thus, several flasks containing eggs were dropped into the squid tank one at a time, coated with a different protein each time. The sight of the eggs attracted the male squid to the flask and the scientists were able to record behaviors of these squid upon their touching the flasks. The experiment showed that the protein β-microseminoprotein was the one causing the male squid's aggressive behavior. The pheromone, according to the researchers, causes the longfin male squid to attack each other in order to prove to the female longfin squid which males are the strongest and therefore, best mating partners. This experiment and research has lead scientists to look into similar proteins in mammals to see if there are behavior similarities in mammals as well, specifically human beings.

This study has lead researchers to look further into the proteins contained within the semen of mammals to determine whether or not human beings or any mammals for that matter display similar behaviors when in contact with specific proteins. Current research shows that there are in fact microseminoproteins present within in mammal semen; however, the functional effect of these proteins has not been determined yet. Thus, experiments such as these are applicable to today because scientists can better understand human nature and why men and women act the way they do in certain situations. This research could help determine specific biological evidence as to why human beings make some decisions or act certain ways.

This article is interesting because animals as simple as squid behave completely abnormally because of something as tiny as a protein. Squid have territorial actions based upon simple pheromones in order to prove that they are the strongest mating partners of all other male squid. Questions arise based upon this experiment because it makes scientists wonder if humans act unnaturally or differently based upon proteins or pheromones that are present without our knowledge. The possibility that there may be pheromones that spike emotions in human beings or other mammals once present within the environment is now questioned by researchers. It will be interesting to see what researchers will do with proteins similar to the one found on squid egg capsules if any are found to have similar effects upon human beings.


http://news.nationalgeographic.com/news/2011/02/110211-squid-pheromones-fighting-mating-woods-hole-animals-science/