John R. Trevithick, PhD, A Canadian Vision Research Pioneer Leaves Us at Age 82.

It is my sad task to note the passing of John Trevithick, PhD, at age 82, at his home in London Ontario. (2/20/2018)

John is well known to many ARVO (Association for Research in Vision and Ophthalmology) and ISER (International Society for Eye Research) members, since the early 70’s as one of the first researchers who took up the lens as a model for cell differentiation. A pioneer in the explorations of cAMP in N. Crassa, he sought to explore this signaling molecule in mammalian cell differentiation. The lens epithelial to fiber cell transition continues during the entire life of the mammalian lens.

            Along the way John explored cataract mechanisms of course but as a biochemist he always was interested in the fundamental knowledge of cell physiology and biochemistry that could be revealed. His lab was one of the first groups to optimize culture media conditions to permit the study of whole living lenses in tissue culture. This permitted the precise manipulation of external and internal chemistry and was used to correlate research done with diabetic rat models and the RCS model. Interesting effects on the RCS lens posterior opacity caught his attention in this model, where degeneration was occurring in the retina. Along with diabetic cataract models his group explored the contribution of antioxidant biochemistry to degenerative processes in the lens and retina. Some surprising findings, of dramatically slowing cataract formation and other degenerations by supplementing endogenous antioxidants resulted in a couple Nature publications. I joined his lab in 1988 as a PhD student, at the University of Western Ontario.

            John took me, and other students, to many meetings around the world and he spent a lot of care teaching us to repeat work and make sure we published reproducible data. He let us write papers early and we tended to graduate with a few publications already completed. With John, I enjoyed discovering that the diabetic rat lens was iso-osmolar for several weeks by dumping Taurine and free amino acids to perfectly balance the increase in sorbitol. Then this amino acid deficiency led to the loss of GSH, ATP production, ion transport capacity, and finally the loss of fluid regulation. This was a lesson John taught many of us, that if you delve into the biochemistry of even an old model system, you will likely find some new knowledge. Do not assume that a decade of literature on a topic has documented everything important.

            John was Emeritus professor of Biochemistry and had continued also as a professor in Kinesiology, working to explore the effects of exercise on the eye in normal and diabetic rats, working with Tom Dzialoszynski and Earl Nobel. Most recently they spent the last several years on space radiation effects upon the lens. That work, funded by the Canadian Space Agency, involves trips to UBC and the use of their busy cyclotron facility. John, always curious to the very end and finding ways to fund vision research in Canada, which does not have a vision-focused funding category as we have in the USA.

If any members of the vision research community have a memory of John Trevithick they would like to share, please email to me at 

Mitton@oakland.edu

Tom and I are planning to write a short memorial paper about John and his contributions to vision science in Canada and internationally. Many of us owe our thanks to John for the time he devoted to ARVO, ISER, vision science and teaching the next generation of scientists.

A mostly complete list of John Trevithick’s publications in PubMed are found here:

John Trevithick Papers in PubMed

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On the pathway to having to teach your own kids: Teacher Shortages in all States as Americans treat teachers so bad.

From twitter @kpmitton:

 #Education in #TrumpVos era. 

Americans treat teachers so bad, soon they will have to teach their own kids! 
#Teachershortage in 50 states. 

Some states are lowering certification requirements so you do not even need a college degree.

#OKLAHOMA’s TEACHER OF THE YEAR leaves state! 

Read more about Student Suicide Investigation; and DeVos Proposes New Student Loan Rules  to make it harder for students to get money back when defrauded by for profit colleges.

  Http://n.pr/2ETJ0Fr

Being A Girl: A Brief Personal History of Violence

A very good read. A very important read.

The Belle Jar

1.

I am six. My babysitter’s son, who is five but a whole head taller than me, likes to show me his penis. He does it when his mother isn’t looking. One time when I tell him not to, he holds me down and puts penis on my arm. I bite his shoulder, hard. He starts crying, pulls up his pants and runs upstairs to tell his mother that I bit him. I’m too embarrassed to tell anyone about the penis part, so they all just think I bit him for no reason.

I get in trouble first at the babysitter’s house, then later at home.

The next time the babysitter’s son tries to show me his penis, I don’t fight back because I don’t want to get in trouble.

One day I tell the babysitter what her son does, she tells me that he’s just a little boy, he doesn’t know…

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Hurricane Andrew: Working in a Category 5 Storm

THis is a great article from the National Hurricane Center blog, also hosted here on WordPress. This story dating from Hurricane Andrew, tells the story so well of what the NHC provides and why even the NHC itself needed a modernized hurricane proof center to keep those hard working forecasters safe when the world is being shook hard.

NHC

Source: Hurricane Andrew: Working in a Category 5 Storm

Our Lab’s latest publication: Norrin treatment testing for survival of optic nerve cells.

Norrin treatment improves ganglion cell survival in an oxygen-induced retinopathy model of retinal ischemia.  In Experimental Eye Research (2017), accepted, in press.

RGCellLivingEye

 

Highlights
• Norrin treatment accelerates recovery of the mouse OIR model from ischemic insult.
• SD-OCT can compare NFL/GCL (nerve fiber layer/ganglion cell layer) thickness in vivo.
• Norrin treatment counters thinning of the NFL/GCL in the mouse OIR model.
• Norrin treatment increases the surviving population density of RGCs in OIR retinas.

This paper is one of the first to use the in vivo imaging methods of intrinsic fluorescence with a transgenic mouse strain to see individual ganglion cells in the living mouse eye, and to even follow their morphology over a period of many days in the mouse model of oxygen-induced retinopathy. This was done with a Phoenix Research Labs‘ system, in this case the Micron-III version of their imaging system. We used a light filter set recommended by Phoenix to image yellow-fluorescent protein (YFP). Axons and dentrites could be seen on single cells in anesthetized mice. Amazing!

We also employed SD-OCT (Spectral Domain – Optical Coherence Tomography) to capture 3D structural records of the mouse retina and then to measure the changes in thickness of the very thin Nerve Fiber Layer / Ganglion Cell Layer (NFL/GCL).

The ability to use these imaging systems in vivo, which are also used in clinical analysis of the Human retina, enables us to see disease processes as they progress and to use far fewer mice to get the answers to research questions. In this case we were testing the ability of Norrin (Norrie’s Disease Protein) to be used to help avascular regions of retina recover their vasculature more quickly and improve the survival of RGCs (retinal ganglion cells) from the stress of low oxygen. RGCs are the cells that form our optic nerves. Millions of RGCs per eye have axons that extend all the way into connections with our brain. This bundle of a million “wires”, or axons, is the optic nerve.

Our research here and that of other laboratories suggest that Norrin and other agents might have use to maintain a better vasculature in diseases where the blood vessels and capillaries are damaged, such as ROP, Diabetic Retinopathy and AMD.