- Number 365 |
- June 18, 2012
A Family Affair With Science
Three members of the Leiske family –
son Christopher (left), daughter Danielle
and father Daniel – pause during their work
at Beam Line 1-4 at the Stanford
Synchrotron Radiation Lightsource to pose
for an impromptu family portrait.
Photo by Mike Toney
Of the hundreds of scientific papers based on research at SLAC’s Stanford Synchrotron Radiation Lightsource each year, some immediately grab the attention. For example, when we saw a paper on human meibum published in the Biophysical Journal by three people named Leiske, we had to learn more. Meibum is an oily substance in human tears that locks the tears onto the surface of the eye, and there's something undeniably intriguing about the image of using SSRL's X-ray beams to study tears.
All was explained when we reached Danielle Leiske, who conducted the research as a member of Stanford University Professor Gerald Fuller's group and is now a postdoctoral researcher at a small startup in Mountain View, California.
Who are the other Leiskes listed as authors on the paper?
DL: Daniel is my dad and Christopher is my brother.
How did they find out about your research at SSRL?
DL: I told them I was getting beam time to do some X-ray scattering. My brother is a chemist by training and he was really interested in the instrumentation side of things. I wasn't doing anything that required a lot of specialized knowledge of sample prep, so I told him if he wanted to come and help me he could. My dad had a high school reunion in this area the same weekend and said, "I could fly down a couple of days early and help you with the beam time, then go to my reunion."
Don't they work?
DL: My dad is a biologist by training; he's a fermentation scientist at Amgen. My brother works at Seattle Genetics in the research department. They both used vacation to come down. I felt a little guilty about my brother. He came here on vacation, and I think he worked 11-hour days.
Describe what you did.
DL: We tested 26 samples of meibum. It comes out of glands in the top and bottom of your eyelids. You can put pressure on both sides of the lids and scrape it off. The samples we used were about the consistency of earwax. We wanted to test each sample at four or five temperatures, slowly going up in temperature with each exposure. It took a long time.
What where you looking for? What did you learn?
A lot of researchers have been studying eyes for a long time, but so far not many engineers have picked up on the tear-film problem. It's interesting because the structure and the function of this tear film are pretty complex. It has hundreds of different lipids, hundreds of different proteins, hundreds of different mucins (mucus-producing proteins). And it has to stay continuous over your eye between blinks.
The film slowly thins over time, and when you blink, you reset the thickness. When you have dry eye, the tear film thins too quickly and it starts to de-wet, and you get these dry spots on your cornea. There's a lot of interesting physics and chemistry going on.
We found that meibum contains crystalline structures that melt at two distinct temperatures. We think these structures cause meibum to have unique mechanical properties that are important to tear-film stability. The mechanical properties and structures might be different in meibum from dry-eye patients; eventually we would like to measure this.
Did your father and brother help you write the paper?
DL: They both read it and made some comments, but they didn't help write it.
Is this the first time you've had beam time at SSRL?
DL: It is the first time. I helped write the proposal – it was fun! I did have a lot of fun. I think this was a great opportunity. It's not something you have access to very often.
And of course Dad gets the last word …
Dad: I have to say it was a very proud moment for me to work with my kids, now both scientists in their own right. It was a great experience that I will never forget. The frosting on the cake was seeing the paper that Danielle wrote using the data that we collected while at the SLAC facility. It was truly amazing to see Leiske, Leiske and Leiske all together as authors.
Was it worth using vacation time? No doubt about it.
Submitted by DOE's SLAC National Accelerator Laboratory