Artificial hearts have been in the news a lot lately--and we understand that engineering them has been ever so tricky, what with all the requirements for pumping and electronics and the risk of blood clots and so forth.
But trying to mimic a heart--for all its impressive four chambers and its fancy valves--is a gentle stroll round the block compared with attempting to mimic another, less handsome (nay, downright slimy-looking) organ: the liver.
This month being National Liver Awareness Month, we decided to find out more about this unglamorous but oh-so-important organ.
We learned, among other things, about a fab-sounding Halloween party game in which you take turns tossing a slab of beef liver into a caldron. (We also found a recipe for liver cookies, which I will bake and serve the next time I'm feeling evil.)
Then we discovered that a band of Canadian fifth-graders in Stittsville, Ontario, had developed a collection of "Digestive System and Healthy Eating Board Games" (http://grassroots.mediacentre.com/2001/OCDESTIT3/index.htm). This seemed more promising.
In the kids' games--called things like Down the Hatch and Bits and Bites--you meander down hand-drawn, squiggly paths that look suspiciously like guts and answer questions about the liver and intestines and digestion and stuff. Things like "How much does the liver weigh?" (Answer: 31/2 pounds.) And (true or false): "The liver produces juices in the mouth?" (Answer: False.) Or yet: "How do you spell intestine?" (Answer: Intestine.)
From games like these and Digestive Cats (a particularly wild and tangled intestine board with distorted, different-sized squares designed to "make it more challenging"), I now know that the statement "The more salt you eat the better it is for you" is false; that an apple is healthier for you than a chocolate bar; that your stomach growls because it is empty; that you can swallow while upside down because muscles in the esophagus stop food from tumbling back into your mouth.
All good fun, but from a knowledge-of-the-liver perspective I needed to dig deeper and reluctantly moved on.
From other, more scholarly, sources I learned that the liver gets perfused with 21/2 pints of blood a minute and does so many things that "a chemical company would require a plant covering several acres to perform its simpler tasks," as one British liver disease Web site put it. "The more complicated ones it could not do at all."
The liver makes Vitamin A. Stores vitamins. Makes blood-clotting substances; metabolizes fats, proteins and sugars; removes all kinds of toxins (including alcohol) from the blood; does differential equations
The list goes on and on. Cholesterol is one of the chemicals that the liver dispassionately disposes of--sometimes in the face of ridiculous assaults. One old medical report describes an 88-year-old man who ate 25 soft-boiled eggs a day for 15 years. He had normal blood cholesterol levels--partly, it appeared, because his liver was working overtime spitting out the excess cholesterol in bile (http://arbl.cvmbs.colostate.edu/hbooks/pathphys/digestion/liver/ index.html).
(We are not recommending you do likewise.)
Finally, the liver is very clever. It can regrow if part of it is lopped off, and somehow it knows what size it wants to be.
The few times baboon livers were transplanted into people, they grew to become human-sized. And big dog livers, when transplanted into small dogs, shrink down to small-dog size.
Scientists have even done experiments in which small bits of liver are put in odd parts of an animal's body. The pieces just sit there, not doing much of anything ... until part of the animal's liver is removed.
Then they just start growing and growing ....
If you have an idea for a Booster Shots topic, write or e-mail Rosie Mestel at the Los Angeles Times, 202 W. 1st St., Los Angeles, CA 90012, firstname.lastname@example.org.