August 21st, 2008

moon

Connective Tissue & Female Hormone QUESTION

K told me (and it seems that it is well known) that women are more likely to strain their tendons and ligaments immediately before their periods, that is, during the end of the luteal phase when progesterone and estrogen from the corupus luteum are declining and near (or at) their nadir, and FSH and LH are low as well. So, can anyone explain to me what the relationship is between the female cycle, hormones and connective tissue?

Thanks in advance.
moon

Africans More Susceptible to HIV

Africans are more susceptible to HIV because of an adaptation to malaria. It happened by evolution: the Africans who didn't have a certain surface protein on their red blood cells didn't get malaria, because the parasite couldn't get into the RBC's. The particular kind of malaria died out, after everyone that was left was no longer susceptible to it.

That same adaptation that allowed the Africans to survive that strain of malaria also resulted in a change in the genetic makeup of the entire population... and now that change is causing them to be more susceptible to HIV. And estimated 90% of Africans and 60% of African Americans are up to 40% more vulnerable to infection by HIV.

There "has always been this myth that people in sub-Saharan Africa were more likely to get HIV because of differences in their sexual behavior, or that they are more promiscuous" (Dr. Ade Fakoya of the International HIV/AIDS Alliance on BBCnews.com)... but now we have a good reason, aside from promiscuity, for the high infection rates in Africa.

In immunology we were taught that the European populations who are descended from survivors of bubonic plague are less likely to get HIV. So it turns out that your genetic makeup makes a big difference in your susceptibility to HIV, and that probably HIV/AIDS will cause a new layer of evolution in our species. Natural Selection is still operating in humans.