Stories tagged Life Science

Nov
04
2010

Disease Detectives
Disease DetectivesCourtesy Disease Detectives
Earlier this year I got the chance to work as the crew of high school staff in the Kitty Andersen Youth Science Center (http://www.smm.org/kaysc/) at the museum to create a series of web-based videos about infectious diseases for the Disease Detectives exhibit. We worked from January through August learning video production skills, learning about different infectious disease topics, talking to experts and folks on the museum floor. We're just getting the videos online now, and all of our videos will be on the exhibit website soon (www.diseasedetectives.org) but I wanted to share them here as well.

For this video, titled "Got Beef? The Story Behind Antibiotics and Livestock" the crew to a slaughter house on in South St. Paul, the Minnesota Department of Health, U of M St. Paul (at 7AM to see the cows grazing), Mississippi Market Co-op, and did hours of research, prep, and post production.
Got Beef? The Story Behind Antibiotics and Livestock from Disease Detectives on Vimeo.

You can check out the video here.

Oct
15
2010
It's Friday, so it's time for a new Science Friday video. Science Friday
Science Friday
Courtesy Science Friday
Today,
"Reporting in the journal Science, Paul Kubes and colleagues filmed immune cells called neutrophils finding their way to a mouse's wounded liver. The researchers wanted to understand how neutrophils find injuries when bacteria aren't around to signal the damage."
Sep
22
2010

Salmonella invades human cells: Color-enhanced scanning electron micrograph showing Salmonella typhimurium (red) invading cultured human cells.
Salmonella invades human cells: Color-enhanced scanning electron micrograph showing Salmonella typhimurium (red) invading cultured human cells.Courtesy Rocky Mountain Laboratories,NIAID,NIH
More than half a billion eggs were recalled after Salmonella sickened over 1600 people (according to the Center for Disease Control, or CDC in September.) That’s a lot of eggs, and a lot of sick people.

What is this nasty bacteria that makes us wonder whether we should let our kids eat raw chocolate chip cookie dough, even as we sneak several spoonfuls when they’re not looking?

Salmonella enterocolitis is one of the most common types of food poisoning and is caused by the bacteria Salmonella Enteriditis. You can get a Salmonella infection by swallowing food or water that is contaminated with the salmonella bacteria. Often, the culprit is surface contamination from raw chicken and raw or undercooked eggs. In most people, it causes diarrhea, fever and abdominal cramping, but young children and those with weakened immune systems are at greater risk of dehydration and more serious infections.

Why don’t they just wash the eggs better? Salmonella bacteria live in the intestinal tracts of animals and birds and can infect the ovaries of healthy-looking chickens. This allows bacteria to infect the eggs even before the shell is formed and voila- you have a pathogen that can’t be washed off of the egg because it’s inside. Salmonella bacteria are often found in the “white” of an egg, although they can migrate to the yolk as the raw egg sits in your refrigerator. Organic and free range chickens have less disease than factory-”farm” raised chickens, partly because of healthier diets and less crowding. Cooking eggs until the yolk is solid kills Salmonella bacteria.

How can you make your cookie dough and eat it too? Buy pasteurized eggs (you can find them at most grocery stores) that have been heat-treated to kill bacteria, but are still essentially raw for all cooking and baking purposes.

Also, remember to wash cutting boards you’ve cut meat on with soap and water before cutting anything else on them, or just have separate cutting boards for meat. Don’t forget to wash your hands after handling raw eggs! Pet food and reptiles can also harbor salmonella bacteria, so have your kids wash their hand after handling either!

Bacteria are everywhere. Some keep you healthy and some make you sick, but making good decisions in the kitchen can keep you and your family from being affected by food-born illness!

(This blog post was originally posted on the Kitchen Pantry Scientist blog.)

Sep
10
2010

Dear Tooth Fairy: You can't handle the tooth! (At least not if a new research idea becomes popular)
Dear Tooth Fairy: You can't handle the tooth! (At least not if a new research idea becomes popular)Courtesy Rev Dan Catt
A new study just published in the Journal of Biological Chemistry says our third molars - aka wisdom teeth - could serve as an excellent source for stem cells. Rather than yanking them out and discarding them (often under our pillows), the molars could be kept as a repository of stem cells for our own use in regenerative medicine. The Japanese study, which was led by Yasuaki Oda, states cloned cells derived from wisdom teeth closely resemble embryonic stem cells.

It sounds like wise use of what's otherwise considered medical waste, but don't be surprised if the Tooth Fairies' Union says it bites.

Aug
13
2010
It's Friday, so it's time for a new Science Friday video. Science Friday
Science Friday
Courtesy Science Friday
Today:
"Plants have a reputation for staying put. But some plants are moving so quickly, we can't see their motions. Biologist Joan Edwards and physicist Dwight Whitaker broke out the high-speed cameras to capture the story of exploding peat moss. The research was published in the journal Science."
Jul
20
2010

Jackalope 1
Jackalope 1Courtesy Joe
I moved recently. And I love my new neighborhood. Great neighbors, lots of kids for my kids to play with and my backyard is frequented by a real live jackalope.

I am obsessed with jackalopes. I don't know why. In the old Science Museum of Minnesota there was, at the end of the skyway, a rack of display cases and one held a jackalope. I would just sit and stare at that thing - for whatever reason it fascinated me.

Jackalope 2
Jackalope 2Courtesy Joe
And then a group of my coworkers gave me a mounted jackalope head that hangs in my cube.

And now one hangs out in my back yard. And it is awesome. Though a little camera shy.

Jackalope 3
Jackalope 3Courtesy Joe
Jackalopes don't have antlers like a deer or moose - in fact they are not meant to have the "antlers" at all. The growths are the restult of the Shope papilloma virus which causes tumors to grow on the rabbit’s head. Interestingly, Shope papilloma virus provided the first model of a cancer caused by a virus in a mammal and has been used to help develop the HPV vaccine and investigate antiviral therapies.

Here’s a link to a couple of photos of rabbits that have more severe cases of the infection.

Jun
16
2010

A sperm whale: You will never get my precious iron feces! Never!
A sperm whale: You will never get my precious iron feces! Never!Courtesy Pacman
It would be a very special day indeed if a better story than this one popped up. But I wouldn’t ask for that. How could you want any more than this: whale poop fights global warming*.

Sperm whales are the particular focus of this study. The population of sperm whales in the Southern Ocean (the waters around Antarctica) is thought to be about 12,000. (There are more sperm whales in the world, but the study looked at Southern Ocean sperm whales.) Those 12,000 whales are thought to put about 200,000 metric tons of the greenhouse gas carbon dioxide into the atmosphere each year. That’s about the same amount that 40,000 passenger cars contribute each year. Destroy those polluting whales, right?

Wrong! See, it turns out that these sperm whales are also responsible for the removal of 400,000 metric tons of CO2 each year, making up for the amount they produce two times over. Their secret is this: they poop iron.

They don’t only poop iron, but sperm whales poop a lot of iron—each whale is thought to defecate about 50 metric tons of iron each year. That’s over 300 pounds a day! Obviously the whales aren’t pooping out solid iron ingots, though. It’s mixed in with their liquid feces. And that’s important.

The whales themselves don’t remove those 400,000 tons of CO2. They’re removed by phytoplankton. Phytoplankton are microscopic organisms that, like plants, use sunlight and CO2 to build their bodies. And they feed on iron.

The whales have lots of iron in their diets, because of the large amounts of fish and squid they eat. So the iron-rich whale poop is an ideal nutrient for phytoplankton. When the phytoplankton dies, the carbon they contain falls to the bottom of the ocean instead of being released back into the atmosphere. Where more carbon is trapped than is released back into the atmosphere, it’s called a “carbon sink,” and that’s what whale poop and phytoplankton create in the Southern Ocean.

Other parts of the ocean may naturally contain more iron for phytoplankton, but the Southern Ocean is poor in the nutrient, and the microorganisms rely on an iron cycle that the whales apparently play a large part in. More whales, greater carbon sink. Fewer whales, less whale poop, more atmospheric carbon.

Coincidentally, the International Whaling Commission will be meeting next week, to discuss regulations on how many whales can be harvested from the oceans each year. It’s a complicated world, isn’t it?

*I thought about making the headline “Whale poop is ‘green’” but… yuck.

Jun
04
2010

Roooaaaarrrr!!!: I have the poison in me!
Roooaaaarrrr!!!: I have the poison in me!Courtesy http://www.flickr.com/photos/kuroha/638778686/
Like all ogres, Shrek is a greedy and covetous beast. He has millions of fine, fine goblets, but should you attempt to drink from any one of them, you risk becoming the target of one of his powerful cancer spells.

“But, Shrek,” you say. “You have so many wonderful cups, brought to us by McDonalds and Shrek 4 Eva. Why can’t I drink from just one of them?”

“Because,” Shrek would surely reply, “they’re all mine. All of them! That’s why I put cadmium in them. Ogres are immune to cadmium, but it is a carcinogen in humans.”

“A carcinogen? In your cups?” you ask.

“Yes, a carcinogen. With long term exposure, carcinogens can increase your chances of developing cancer!” says Shrek.

“Cancer?” you say.

“Yes. Cancer,” says Shrek.

And it’s not only Shrek’s goblets that are cursed; drinking from the cups of Princess Fiona will soften your bones, and sipping from the vessels of Puss in Boots will cast the hex of severe kidney damage upon you. And you should never drink out of something called “Donkey,” no matter what it’s made of.

Fortunately, all of the cups are being recalled to Ronald McDonaldland, to become a part of Ronald’s personal collection. Because clowns feed on poison.

May
28
2010

This could be you: (Again, only if you were a snail.)
This could be you: (Again, only if you were a snail.)Courtesy Thomas Hahmann
I'm not going to get into the full parasite extravaganza here, because Wired Magazine already laid it out pretty well, but here's the general idea:

What if some worm eggs snuck into your body through something you ate (something gross)? What if one of them lodged itself in your liver, and, after a little while, started producing embryos of its own? What if it packed those embryos into giant, pulsating egg sacks that flopped out of your eye sockets and hung from your head? And what if those pulsating egg sacks looked so delicious to birds that they would flap down and eat them (and your eyes)?

It can all happen. I mean, you'd have to be a snail for it to happen to you, but still... Leucochloridium paradoxum is out there.

May
25
2010

I am invisible: And thinking about eating you.
I am invisible: And thinking about eating you.Courtesy Etrusko25
You could be attacked from above at any second. By a shark. Because they are invisible. And you can’t see invisible things. So they can easily attack you.

I mean, you’re not going to get attacked by just any shark. But, really, if there’s an invisible shark hovering above you, about to attack, does it matter what kind of shark it is? That’s like a squirrel wondering if the car that’s about to force its digestive tract out through its lowermost orifice is a Ford or a Toyota. Let’s be practical here.

If you must know, the shark is called a “velvet bellied lantern shark.” (Coincidentally, if you replace “shark” with “head” you have my childhood nickname.)

But the important part, again, is that it can turn invisible.

It’s not quite up to Harry Potter levels, at least—the shark is only invisible from below, thanks to its velvety lantern belly. See, if you’re a weak little prey species flopping pathetically around the ocean (I assume you are), if you see a dark shadow pass overhead, you want to flop pathetically toward some cover, because dark shadows often come from things that can eat you. Like a shark! The underside of this shark, however, is covered with light-producing organs, called photophores, which shine at the same frequencies as the sunlight that filters through the water. That, of course, tricks the other little fishies (and you) into thinking that the shark isn’t there.

It’s more than a little concerning, isn’t it? Don’t worry, though. I’ve been working on a product for just this sort of problem, and I think it’s about ready. It’s an invisible-shark detecting stick. It actually looks a lot like a wooden yardstick, and you can even use it for measuring things up to one yard long, but it’s really meant for keeping you safe from invisible sharks. You use it by holding it above your head at all times. If you feel a pressure on the stick, just look up. If you see a doorway, or a broken light fixture or ceiling fan, you’re probably safe. But if you look up and see only a familiar comforting glow, you should dive for cover. Or, if you carry a firearm, you should shoot wildly into the air above you. Shark crisis averted.

They’re $30. Email me.