Mosquito biting activity increases 500 times during a full moon phase, and they prefer blondes with smelly feet

Mosquitoes appear to prefer blonde people with smelly feet. Did you see the moon last night? Got mosquito spray? Mosquito biting activity increases 500 times during a full moon phase! There are more striking facts in this video excerpt from National Geographic.

The video is part of the Amazing Animals YouTube playlist by National Geographic:



Medical Geek Humor on Twitter

The tweets below are part of the series Medical Geek Humor on Twitter - they recall a TED moment from 2009:

@loic Bill Gates released mosquitoes at #TED we're all leaving the room and getting sick about 4 hours ago from web


@stevewhitaker Don't worry about the buggy mosquitos Gates released at #ted. Microsoft's working on a patch that's due out next year. about 14 hours ago from twitterrific
AllergyNotes Releasing mosquitoes by Bill Gates into a startled crowd at TED described as "an amazing TED moment" http://is.gd/iu0o about 12 hours ago from web

AllergyNotes Gates spreads malaria message with mosquitoes http://tinyurl.com/cxwo2e 12 minutes ago from TweetDeck

pyknosis Nice to hear Bill Gates picked up a hobby during his retirement: entomology. http://is.gd/izJn (Not surprised he likes the blood-suckers.) 14 minutes ago from web

pyknosis Don't get me wrong. Not saying B Gates is a bad person. He's not. He just created and championed software that can suck the life out of you. 12 minutes ago from web
pyknosis BTW, now that I understand the context, I think this is a winner of a tweet: http://is.gd/izK5 11 minutes ago from web: "If Steve Jobs had released mosquitoes, everyone would be wanting one."

If you are included in this post but would like to have your tweet removed for any reason, please email me and will comply with your request the same day.



Comments from Twitter:

Vijay @scanman: Mosquitoes are mini-vampires

Tariq @ucisee: Mosquito biting activity increases 500 times during a full moon phase - "appear to pref blonde with smelly feet."

Kathy Mackey @mkmackey: Ha! No one likes full moon!

The Third Component of Genetic Blueprint - Writing in Pen (DNA) vs. Pencil (Epigenetics)

The term epigenetics refers to changes in phenotype (appearance) or gene expression caused by mechanisms other than changes in the underlying DNA sequence, hence the name epi- (Greek: over; above) -genetics. There is no change in the underlying DNA sequence of the organism; the phenotype is expressed by activating some genes while inhibiting others. Epigenetics includes changes in gene function that occur without a change in the sequence of DNA. These changes occur as a result of the interaction of the environment with the genome. Epigenetic determinants activate or silence fetal genes through alterations in DNA, histone methylation and acetylation.


DNA associates with histone proteins to form chromatin. Image source: Wikipedia, GNU Free Documentation License.

From the National Geographic magazine:

"Mother Nature writes some things in pencil and some things in pen. Things written in pen you can't change. That's DNA. But things written in pencil you can. That's epigenetics. Now that we're actually able to look at the DNA and see where the pencil writings are, it's sort of a whole new world."

If you think of our DNA as a piano keyboard and our genes as keys - each key symbolizing a segment of DNA responsible for a particular note, or trait, and all the keys combining to make us who we are - then epigenetic processes determine when and how each key can be struck, changing the tune being played.

Recent studis focuses on a particular epigenetic process called DNA methylation, which is known to make the expression of genes weaker or stronger.

The good news is that some of these processes, unlike our DNA sequences, can be altered. Genes muted by methylation, for example, sometimes can be switched back on again relatively easily. And though it may not happen soon, the hope is that someday epigenetic mistakes will be as simple to repair as a piano that's out of tune.
"


Human chromosomes (grey) capped by telomeres (white). Image source: Wikipedia, public domain.

References:

Twins. National Geographic magazine, 01/2012.

Portrait of twins: series one and series two from National Geographic.

Twins Data Reshaping Nature Versus Nurture Debate. NPR.

Epigenetics, Wikipedia.

First Gunshot Victim in the New World - National Geographic Video

Archaeologists in Peru have discovered the 500-year-old skeleton of a man who died from a gunshot wound. Experts believe he's the first shooting victim in the New World.

Survival Guide: Rattlesnake

More than 20 000 persons worldwide die of snakebites every year. A snakebite is a true medical emergency.



NationalGeographic video: A bite from a rattlesnake can be lethal, but a majority of snakebite victims survive their encounter. Do you know what to do if are on the receiving end of a rattlesnake bite?

Tips from JAMA: What to do after a snakebite?

- Try to remember the shape of the snake's head and body and the snake's color to identify the type of snake and help direct the treatment. A photo, taken from a safe distance, may be helpful.

- Keep calm and move around as little as possible. This may limit the spread of the snake's venom.

- Do not use tourniquets or suction devices. Do not cut the area around the bite. These traditional remedies do not help and they may harm the patient, making the situation much worse.

- Antivenin, specific to the type of snake responsible for the bite, may be given in case of severe envenomation. This helps neutralize the effect of snake venom in life-threatening or limb-threatening snakebites.

- Intensive care and life support may be needed for the most severe cases of snakebite, especially in small children or elderly persons.

- A tetanus immunization may be given if you have not had one recently.

Read how to prevent a snakebite here: Snakebite - JAMA Patient Page, 2012 (PDF).

References

Snakebite - JAMA Patient Page, 2012 (PDF).

Related reading

See the other videos in the series Survival Guide.