Electrowhatscapy?

It is fun to tell people that I am an Electron Microscopy Tech. If they don't have any idea what that means, I just tell them that I am a scientist that makes really small things really big. I will attempt to give a reasonable and understandable (and interesting hopefully) explanation of what I do.

When you go get a tissue biopsy (like on your liver, kidneys, or cancer...) and they say that they are sending in the tissue for testing: that's me. We get the tissue and send it through a process to remove the water and fix the cells in place, then we embed it in little plastic blocks. We cut thin slices of tissue from these blocks on a machine called an ultramicrotome. (looka lika dis:




Just to start with the perspective of how small we are talking here, a hair is about 130 micrometers across. (0.13 cenitmeters, .05 inches, super tiny.) Our thick cuts from this plastic block we take at 1 micron (micrometer). So we could split a hair about 130 times. After deciding what we want, we take the thin cuts. We aim for about 70 nanometers (.07 microns, .0007 centimeters, 0.000273 inches, super teeny tiny). So we could split that old hair about 1857.14 times. Yeah, that many times.

So we put these thin slices on a little copper grid that is about as big as this: o. We stain this with depleted uranium and lead then stick it into the electron microscope. Mine is the model just older than this (if you can believe that):


So then you power it up and shoot what is essentially lighting and radiation through the section, and this is what we see:




Cilia: These are hairs that grow out of small ridges on the surface of cells in your nose, throat and lungs. These are the small things that beat and move the crap back up and out of your body. We look for deformations that are too difficult to explain here. But this picture is at about 200,000 times magnification, and is a cross section through a few. You can see some that are cut across more longways there too. Kinda cool.



We also look at small intestine. The idea behind the grand design of the bowel is to increase surface area. The more you twist and turn the thing, the longer it can be, then you wrinkle it, giving it greater length. On the cellular level, you make the surface of the cells bumpy so you get more area to absorb and trap all the goodies that you want inside the body. On the pink picture on the left, you can see about 200 cells or more and you can see the bumps they collectively form. Then on top of all of those bumps are the neato things that I look for. The technical terms for the bumps are villi and I look for microvilli. So to recap: twist, wrinkle, wrinkle again, then wrinkle that and you get this:


Just a side note, the white spiderwebby looking thing on the left is a goblet cell, it puts out a ton of mucus to slick up the guts. Cool huh? (you can see about 5 cells here.) And the cilia that was up above here is about 1/3 the size of the little microvilli on the top of these cells.





So onto the liver. There it is. You make bile in your liver that helps you digest fat. This is made in individual cells and is gathered until it is all together in a tube that is about as big around as a pen, this goes into the gall bladder where you squirt it onto those fries. You can see in between the cells, a little space where the bile is gathered, helpfully marked by the arrows. The little gray squigglies are where the bile actually comes out of the cell. You can see about 4 cells here. (the dark and light bands across the picture are microscopic vibrations from the diamond blade as we cut the plastic.)

Finally the kidney. I won't go into super detail here, but here is the big part. Your kidneys are giant filter pee makers. The first and biggest filter is the glomerulus. All the blood goes into the "glom" and everything but the red blood cells and big proteins goes out into the filter. Later everything you need gets put back in, leaving out the things you don't that you pee out. A huge glom is about the size of a period here: . And that is huge, most are quite a bit smaller. Here is one under a normal microscope:

So you can see the little holes (the really little ones inside that look kinda pink and are based in the brown parts...) These are the little blood vessels, big enough for one red blood cell to go through at a time. These are capillary loops, we call them loops from now on.

Here is a relatively normal set:

The little dark hair looking fingery things on the outside of the loops are called foot processes and the loops look good and normal thickness.






This is what happens when you take a whole bunch of ibuprofen for a long time. They tell you that it is bad for your kidneys, and this is why. Those little fingers get all pushed together and you can't filter stuff real well, so you get blood and protein in your urine. You can see that the fingers don't poke up here, they are more just a dark band now.


Diabetes and high blood pressure make the loops real thick, which also makes it hard to filter. These loops are about 4 times the thickness they should be.

Some diseases and after bad infections your body tends to just stuff crud where it shouldn't be. The dark spots in the lighter places here are these "deposits." Here are a few to see what I mean. You can see that you can't even tell where the loops are, or what is where. This = sick person.


















Tah-dah