Posts Tagged ‘NASA scientific discovery’

An Eye in the Sky Makes It Dangerous to Fly

 :: Posted by American Biotechnologist on 10-24-2013

Just 13 days in space may be enough to cause profound changes in eye structure and gene expression, report researchers from Houston Methodist, NASA Johnson Space Center, and two other institutions in the October 2013 issue of Gravitational and Space Research.

The study, which looked at how low gravity and radiation and oxidative damage impacts mice, is the first to examine eye-related gene expression and cell behavior after spaceflight.

“We found many changes in the expression of genes that help cells cope with oxidative stress in the retina, possibly caused by radiation exposure,” said Houston Methodist pathologist Patricia Chévez-Barrios, M.D., the study’s principal investigator. “These changes were partially reversible upon return to Earth. We also saw optic nerve changes consistent with mechanical injury, but these changes did not resolve. And we saw changes in the expression of DNA damage repair genes and in apoptotic pathways, which help the body destroy cells that are irreparably damaged.”

Since 2001, studies have shown astronauts are at increased risk of developing eye problems, like premature age-related macular degeneration. Experts suspect the cause is low gravity, heightened exposure to solar radiation, or a combination of the two.

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Scientific Discovery of the Year or Grandiose Hyperbole?

 :: Posted by American Biotechnologist on 12-07-2010

Towards the end of last week, NASA announced that it would reveal a stunning scientific report in a live press conference that would surely be the scientific breakthrough of the year. Watching the conference later in the day, I was amazed to hear Felisa Wolfe-Simon of the NASA Astrobiology Institute explain that she found a bacteria that can substitute arsenic for phosphate in the DNA phosphate backbone of a newly discovered bacteria. This is truly an amazing discovery that flies in the face of our biology 101 teachings that all DNA molecules across every species contain four nucleotides held together by hydrogen bonds and a phosphate backbone. Her findings were recently published in the prestigious journal Science and I was excited to get the story out to the American Biotechnologist public as soon as possible.

See the video below to hear Dr. Wolfe-Simon summarize her findings during the press conference.

Fortunately, other things occupied my attention that day and I was unable to put the story out on time. When I finally got around to revisiting the story, I came across multiple reports in the blogosphere questioning the methodology used in the study (the study substituted arsenic for phosphate by starving the bacteria of phosphate and adding in arsenic. Yet the cultures were grown in media rich in salt and associated phosphates!) and the outright refusal of the study’s lead authors to answer questions about their findings in online forums. This is quite an insulting position to take and Jonathan Eisen of UC Davis is quoted on Slate.com as saying:

“If they say they will not address the responses except in journals, that is absurd. They carried out science by press release and press conference. Whether they were right or not in their claims, they are now hypocritical if they say that the only response should be in the scientific literature.”

Over the past few days, others have expressed their criticism of the paper or at least of the way the results were hyped and revealed to the public. Many of these opinions have been compiled by Daniel Ocampo Daza on his Ego Sum Daniel Blog. I highly suggest reading his post to get a broad perspective of the various opinions.

Aside from the obvious questions surrounding the study itself, it is interesting to explore how the world of scientific communication is changing. While in the past, criticism of studies published in scientific journals such as Nature, Cell and Science took place in editorial pieces and follow-up scientific publications, widespread access to online media and blogs has made information more accessible and armchair analysis a widespread phenomenon. The internet has provided a forum for industry experts to openly criticize and question shoddy science and has made it more difficult to hide behind the peer review process. I would suggest that we now find ourselves in the period of “author beware.” If you are going to publish your findings, be prepared to defend them under the harshest of circumstances at any given time.

Wolfe-Simon F, Blum JS, Kulp TR, Gordon GW, Hoeft SE, Pett-Ridge J, Stolz JF, Webb SM, Weber PK, Davies PC, Anbar AD, & Oremland RS (2010). A Bacterium That Can Grow by Using Arsenic Instead of Phosphorus. Science (New York, N.Y.) PMID: 21127214