Thursday, April 8, 2010

Bacteria on Easter Island

Bacteria on Easter Island


Rapamycin is a drug that keeps the immune system from attacking and potentially destroying transplanted organs (heart, lungs, kidneys, etc.). This drug has another use, which fights Alzheimers. The drug was first found isolated in soil on Easter Island (Rapa Nui). A team from The University of Texas Health Science Center at San Antonio reported that the drug rescued memory in a mouse with Alzheimers. The team also found a reduced amount of brain lesions, similar to the ones found in humans that die of Alzheimers. Because Rapamycin is a approved United States drug it could be used to start fighting Alzheimers. Three institutions reported that the life of the lab mice was extended. It was the first pharmacologic intervention shown to extend the life of an aging animal.


During a 10 week period mice with Alzheimers were fed chow containing the drug Rapamycin. Each mouse 6 months old (age of a young adult), and showed signs of having Alzheimers. At the end of the 10 weeks the mice were put through the Morris water maze (miniature swimming pool used for memory testing). The brains were then tested to see if the Rapamycin made a difference on the lesions. The drug is also being tested on cancer mice to see if it can stop or help cancer. The conductors of the test are still unsure as to whether or not this could work on humans.


By Venice Gordon, Cindy Cochran, Matthew Winter


Source:

http://www.sciencedaily.com/releases/2010/02/100224165259.htm


Thursday, December 10, 2009

Study Relates Phthalate Exposure to Less-Masculine Play by Boys



The young sons of women who had high concentrations of two common phthalates when pregnant, don’t show the kind of play behavior we normally associate with boys.

A University of Rochester Medical Center study of 145 preschool children shows that where pregnant women have high concentrations of two common phthalates in their urine their young sons play in a less traditionally male way. Phthalates are chemicals used to soften plastics and are commonly found in the environment. People may be exposed to them in foods, soaps and lotions. Scientists believe that exposure to phthalates lowers testosterone levels. Testosterone is a male hormone and is very important for male brain development. Scientists already know that low testosterone levels affect male genital development and that exposure to phthalates may cause this. They are worried that prenatal exposure to phthalates, will also affect male brain development. They are concerned that this will result in changed male behavior.



Boy Playing With Toy Truck Clip Art


In the Rochester study, Dr. Shana Swan, an expert in reproductive health and phthalates, made this hypothesis: If pregnant women have high phthalate levels when their fetus’s male genitals start functioning, their sons’ brain development will be altered and this will affect their play.

From 2000 to 2003 urine samples were taken from women at week 28 of their pregnancies. The samples were tested for two phthalates DEHP and DBP. When the children of these women were between 3 and 6 years old the women answered a questionnaire called the Preschool Activities Inventory. The questionnaire asked about what toys and activities the sons enjoyed. For example, trucks and play fighting rather than dolls and gentler activities. The scientists also asked the parents whether they would encourage or discourage the more feminine play.

The study found that there was a direct relationship between elevated phthalate levels and less “traditional” male play in their young sons. (There was no relationship between phthalate levels in the pregnant women and their daughters’ play behavior).





Questions to Consider:

-What are your reactions to this text?

-Do you think it is true that Phthalate exposure can lead to less-masculine play by boys?

-If so, would you try to prevent pregnant mothers and boys from being exposed to Phthalate?

-What would you do if you had a boy who preferred toys that girls usually play with (e.g. dolls),
or a girl who preferred toys that boys usually play with (e.g. trucks)? (encourage or discourage)

--Does the text agree or disagree with this statement: “phthalate exposure can lead to later sexual development in male organisms.”
---What information would you need to find out, or what experiments would you perform?



Acknowledgments:

Articles on this topic:

http://www.sciencedaily.com/releases/2009/11/091116085040.htm

http://www.urmc.rochester.edu/news/story/index.cfm?id=2689

Information on Phthalates:

http://www.ewg.org/chemindex/term/480

Picture:

http://www.clker.com/clipart-9370.html

Arianne and Lily- Section 2