Mia Salas, Week 2 +Today, Microtomes, Microscopes & Myelin

This past week was a shorter week in lab, because we had off July 3^rd and July 4^th. On Wednesday, Alison presented on her research about Krabbe Disease (which ended up being an hour and a half presentation because of all the questions), but it was still really interesting.  That same day, Gary showed me how to use an inverted microscope and quizzed me on biology/chemistry topics that he taught me last week (luckily I was able to answer most of his questions!).  Then Kate and I went with Dr. Vite, who showed us how to cut organs from cats.  Essentially, most parts of the organism are preserved in 70% ethanol (liver, heart, brain, spinal cord, lymph node, spleen, and lungs). But in order to do tests on these parts of the body, they must be sliced and preserved in a wax-like substance called paraffin so that thin sheets of tissue can be cut. He showed us how to cut each part: some were quite simple, while others were very complicated, such as the brain which has to be cut into eight to twelve different slices, depending on the size of the brain.  These include the cerebellum, frontal lobe, occipital, and brain stem, and these sections each may have one or more slices, again, depending on brain size.  We got to see how to differentiate between these different sections when we cut, especially by looking at the white and grey matter, and Dr. Vite would tell us what each part of the brain is responsible for.  Sam showed us earlier how to then use a microtome to thinly slice these individual tissues to later be used for tests or electron microscopy.   

My individual project also really started this past week.  I will basically be evaluating the effects and efficiency of treatment for NPC on the cats depending on when treatment started (8 weeks, 12 weeks, or 16 weeks). I spent the first twenty minutes of my morning finding the service elevator to meet Patty, who works in the colony with the cats and dogs. But of course I went to the wrong service elevator, because there were multiple, so it took a while. The building is like a maze. Once I found Patty, she showed me were to go to find the records for the cats. I spent two hours in the record room, because all of the cats are numbered, and so there are thousands of files, which are organized, but still take a while to find.  There were about twenty cats that I needed records for, but I couldn’t take them with me, so I had to write everything down.  I recorded the weight of each cat for every 14 days since treatment began.  I still have to enter all of this data on excel and make a graph to display the differences in weight gain for the 8 week group, 12 and 16.  The next step in the project will be to retrieve the bloodwork records of those cats from Jess so that I can track the ALT enzyme and compare the levels of ALT in the blood of each cat.  Again, I will have to make separate graphs on excel for the different times of treatment.  I also have to make a Kaplan-Meier plot of survival, and then when I finish all of that, Dr. Vite said to find him so that we can go over videos of the cats to observe neurological symptoms.  Basically, I won’t be doing a lot of actual lab work for my project, it will more be analyzing data, but I don’t mind because I get to do lab work alongside people in the lab unrelated to my project.  Today Gary took Kate and I under his wing since Dr. Vite was out, and he showed us how to be “experts” as he said on microscopes.  We got to examine tons of images that he already took pictures of, such as seeing what myelinated axons and Purkinje cells look like as stained images.  We practiced adjusting the microscope to prepare it to take a picture, which is actually such a complicated process, but Gary clearly explained each step and why we do each step, and eventually Kate and I got it.   

Hopefully I will get to do more hands on lab work, but I think that will come this week or next week, because Gary said soon we will slice our own tissues, stain them, and take pictures of them underneath the microscope. I also hope Alison will let me shadow her soon and maybe help her out with her research on Krabbe disease, because she is always in the lab micropipetting and doing PCR.  But so far, I am just grateful to be learning so much from everyone.  Tomorrow I'm going to Shake Shack with Dr. Peretz and other EXP people in Philly and Wednesday I'm meeting Elaine and Trung for dinner. I also finally got my Penn ID so I don't have to slide in with other people going into the building! I’m looking forward to seeing what the next few weeks will bring!