My goal is simple.
It is a complete understanding of the universe, why
it is as it is and why it exists at all.
-Stephen Hawking 1988
Whatever you do, don’t be bored; this is the most exciting time we could
have possibly hoped to be alive. The world is smaller than ever before, and humans
daily break down the barriers of communication, distance and ideology that divide
us into isolated groups. At the risk of sounding cliché, I might also
point out that we are standing on the shoulders of giants. One can pick up a
book of physics or calculus and read what it took Einstein, or Newton their entire
lives to flesh out and establish. Human experience and progress is, fortunately
for the students of life, an additive affair.
However, while “book learning” is imperative to any modern student’s
arsenal, a true education is largely experiential. To suggest that any student
could learn to become an original, progressive scientist by sitting in the library
and pouring over the tomes of biology, chemistry and physics would be to deny
the need for original thought in all of us. Like language, in science it is important
to have a basic vocabulary off of which to build; but isolated studying of textbooks
will only lead so far. Eventually any student who is serious about continuing
their education must take the plunge and surround himself or herself with the
unknown, taking their lessons from the results of their own decisions. Enter
the UBRP and BRAVO! programs here at the University of Arizona.
I have just returned from a six-month period as a BRAVO! student in the lab of
Dr. Kevin Brindle at the University Of Cambridge, in Cambridge,
UK. Whilst in
England I was studying the use of MRI as a means to non-invasively monitor gene
expression in vivo. 
The development of a gene reporter with the ability to monitor
gene expression 4-dimensionally (that is spatially, and temporally) would provide
researchers and medics with a currently-unavailable tool to aid in the development
of gene therapy as a treatment for disease. The use of a transporter protein
whose interaction with a probe can be visualized with MRI would allow for its
incorporation into current adenoviral vector therapies; this could potentially
allow for the correlation of the expression of the imaging cassette to the expression
of a therapeutic gene of interest. The end result of such a development would
provide information about the efficacy of gene delivery and expression in living
systems, which is highly variable.
The BRAVO! program gave me the opportunity to hone my laboratory skills in a
world-class research laboratory. I learned molecular biological techniques such
as bacterial transformations, restriction enzyme digests and plasmid purifications
that allowed me to create novel plasmids for transfection of MCF-7 human breast
cancer cells. I learned to use a spectrophotometer and the ratio of 260/280 nm
of a DNA suspension to determine the concentration and purity of my plasmids,
while agarose gels would provide me with verification that my splicing had produced
the intended gene sequence in the plasmid.
When satisfied that I had created adequate stocks of the intended purified plasmid,
I would culture mammalian cells for transfection. Stable transfection is the
incorporation of plasmid DNA into the chromosome of a cell. 
The inclusion of
plasmid DNA into a cell causes the constitutive expression of a protein that
confers resistance to antibiotic for the purposes of selection of successful
transfects. The gene of interest for imaging purposes can be expressed constitutively,
or put under regulation of a specific gene promoter providing great diversity
in potential applications. The transporter in question (isolated from human hepatocytes)
was constitutively expressed on the surface of human cancer cells. The presence
of the transporter was confirmed using a radioactive substrate for in vitro uptake
experiments, while a number of paramagnetic substrates were tested in competition
studies for comparison of potential contrast enhancement in MRI.
Finally, after transfecting a cell line to stably express the transgenic protein,
I injected cells into the mammary fat pads of a SCID mouse to await tumor growth.
The cells in question require estrogen to form tumors; so time-release estrogen
pellets were inserted locally under the 
skin. After about a month, there were
palpable tumors, sufficiently sized for the imaging experiments. A gadolinium-containing
compound was injected into a tail-vein cannula and images were acquired over
a few hours to follow inflow and outflow kinetics of the contrast-enhancing probe.
We were hoping to find differences in pharmacokinetics between the tumor and
surrounding tissue that could be used for detection of gene expression in vivo,
but unfortunately, no significant differences were noted. There were general
trends that suggest new directions in the development of an MRI-applicable reporter
gene.
While doing this research I was treated as a graduate student in the lab. I was
expected to keep myself on track without reminder and to teach myself the techniques
I needed to get the necessary results. In short, I learned what it is to be a
scientist and student pursuing original research.
Other than the positive contributions to my education, experience, and career
as outlined above, the BRAVO! program allowed me to live and work in another
country and culture. Though the US and the UK share many common cultural roots,
history and differences in ideology separate us on many levels. Perhaps the most
immediately noticeable difference being the age of both the city and university
that collectively constitute “Cambridge, UK”. The Romans first settled
Cambridge as a strategic and defendable river crossing. After the fall of the
Roman Empire, the Anglo Saxons, and eventually the Normans won Cambridge. Saxon
and Norman buildings survive in Cambridge, making their oldest buildings some
1000 years older than the founding of our country. The University of Cambridge
was founded in 1289 by Oxford expatriates, forming a congenial rivalry between
the two great schools that lasts to this day; competition and collaboration between
the two universities have led to amazing intellectual progress for hundreds of
years. The English are very proud of their history and their culture, much of
this being rooted in the histories of Oxford and Cambridge. This pride is immediately
obvious when one is in the company of British students who are simultaneously
awed and honored by their surroundings. For an example of the contribution to
academics and science that Cambridge has made to the world, one needs look no
further than a list of Cambridge alumni. Some of the University’s famous
scientist alumni include:
- William Harvey - discovered the circulation of the blood in 1628
- Isaac Newton - worked on gravitation in 1687
- Charles Darwin - described mechanism of evolution in 1859
- Ernest Rutherford - split the atom in 1903
- Crick and Watson - discovered the structure of DNA in 1953
- Professor Stephen Hawking - wrote Brief History of Time in 1988
Only through a somewhat long-term experience like BRAVO! can one truly gain the
perspective of another country’s society, culture and politics. I am, consequently,
a worldlier person than I would have been without this experience. This includes
the perspective gained of the United States by being outside of its borders.
I feel that my ability to be a responsible American citizen has matured tremendously,
and I look forward to a future of developing more discourse between scientists,
policymakers and the public regarding the responsible use of science and technology
in our global society.
Differences in culture and values, and the hurdles that they can represent, are
broken down and understood through education and interaction. Classes and texts
have proven to be a first step in a comprehensive education, but experiencing
the international scientific community firsthand is an amazing way to integrate
a specialist education in science with exposure to worldwide social issues. It
is my intention to strive for a unified global scientific partnership that tackles
problems as the worldwide issues that they are. As the United Kingdom sets up
the world’s first stem cell bank, a hotly contested form of research in
the United States, I am reminded of the fact that the direction of science is
subject to the values of the cultures that it serves. I think that in order for
the scientific community to interact cohesively at an international level on
such contentious issues, it will be necessary for individuals to be ready to
act as scientific ambassadors. This is a term that was used to describe the expectations
of me as a BRAVO! student, but I intend to carry the idea through my entire career.
I have changed my mind; I am glad our search for understanding will never
come
to an end, and that we’ll always have the challenge of new discovery.
-Stephen Hawking 2004
Many thanks to Carol Bender, Dr Gillies, Dr. Brindle and the HHMI for making
this experience possible. Anyone interested in talking to me about my research,
BRAVO! or any other aspect of my life is welcome to contact me at: days@email.arizona.edu
Samuel Day, UBRPer in Dr. Robert Gillies's
lab, Biochemistry and Molecular Biophysics
