The Expert Testimony Continues


In these last few posts, I’ve been recounting the testimony of the toxicology and pathology expert Dr. Vyvyan Howard, in the Castillo-DuPont case.

 

As part of his testimony, Dr. Howard began to talk about the many different ways an embryo or fetus can be impacted by environmental factors, including Benlate. He went on to methodically rule out any other known potential environmental cause that could have affected Donna Castillo:

 

• He considered and ruled out vitamin K;

 

• He considered and ruled out excessive time spent in hot tubs;

 

• He considered and ruled out anything else that could possibly have been involved in this incident.

 

When he had finished with that part of his testimony, Dr. Howard then spoke at length about the process of arrested development and complete cell death (which, by the way, occurs when more than 75% of the cell is affected). In his opinion, that was what happened to Johnny Castillo’s eyes.

 

In one of the studies conducted by Dr. Dick Van Velzen—done at Dr. Howard’s request—cells were cultured in various concentrations of benomyl and then measured for something known as neurite retraction.

 

In a solution of only three parts per billion of Benlate, the researchers measured a significant reduction in the outgrowth of neurites. If such a process were occurring during Johnny’s gestation and the eye cells were waiting for alarm bells to go off, they would not have had the right functional connections to alert them, and the cells would likely have perished as a result. In Dr. Howard’s opinion, this is what caused Johnny’s birth defect.

 

In this test, the cells would either divide normally or something would go wrong because the scaffold on which the chromosomes usually migrated hadn’t formed properly.

 

If something goes wrong in a fetal cell, it just rolls up and dies. Scientists can actually measure the rate at which this happens with a micronucleus test. If you have cells that are dying, it’s because they have been exposed to something harmful.

 

During the developmental process, cells pass through what is called a window of vulnerability. When the eyes, for instance, are in their most critical stage of development, or maximal proliferation, that’s the time when they are most susceptible to certain sorts of injury.

 

This specific window of vulnerability is also known as organogenesis. Organogenesis in humans occurs from week three of gestation to week eight. During that time a number of different structures will form at different intervals. The window of vulnerability for the eyes is during this stage. If the optic vessel is forming and something happens to affect the process, no eye will develop at all; anophthalmia is the result.

 

That wasn’t exactly the case with Johnny Castillo. His cells sustained injury slightly later in organogenesis, so he developed some ocular tissue, which presented as tiny cysts in the orbits where the globes (eyes) would normally be.

 

In other words, the later in the process the arrested development occurs, the greater the chance that there will be some eye formation, even if it’s very, very minimal.

 

In my next post, I will speak a bit about the “moving target” of testimony during a trial.

 

You’ll find much more about the Castillo-DuPont trial, as well as information on my background and my thoughts on aspects of the judicial process, in my book, Blindsided.

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