HASHI, YIQIAN ZHU
University of California, Berkeley
Advisor: Song Li
Tissue engineered vascular graft
Hashi and YiQian Zhu both know that blood vessels that clog and
harden are a critical problem in the health care industry.
One of the usual ways of treating clogged vessels is by
using a graft to bypass the clog and restore normal blood flow.
The graft is usually supplied from a vein or artery
elsewhere in the patient’s body.
and Zhu also know that all too often, bypass grafts can fail.
They realized that another option was synthetic grafts,
but these grafts also have their limitations.
So, the team worked together to experiment with a new
kind of graft. They
take an FDA-approved polymer and create long, thin strands which
are formed into a very thin mat.
Then, the mat is seeded with bone marrow stem cells and
left to culture. Once
the cells have had a chance to grow, the mat is carefully rolled
and formed into a tube. The
tube—their graft—is then ready to implant as a vascular
graft and as a fully-functioning blood vessel.
Chances of rejection are greatly reduced because the
patient’s own cells could be used to create the graft.
to Hashi, “There are currently no tissue-engineered vascular
grafts on the market. The
idea of an off-the-shelf graft ready for the patient in time for
surgery is exciting.”
He notes that it is helpful for him to step back and look
at his projects from an engineering mindset.
He remembers that as a youngster, it was natural for him
to go into engineering because he was good at it.
Not until he was in graduate school did he develop his
healthy respect for biology.
24, of Torrance, California, graduated from South High School in
1999. His parents,
Katsuo and Rumiko Hashi, also of Torrance, still own a
landscaping business in the area.
Hashi received his undergraduate degree in mechanical
engineering from UCLA, and he is currently working on his Ph.D.
in bioengineering at Berkeley.
31, originally from Shanghai, China, has been in the United
States since 2003. A
neurosurgeon by training, his expertise was instrumental in
placing the grafts within the animal subjects and providing the
medical knowledge needed to create the grafts.
Zhu conducted all the in vivo techniques, and is looking
forward to their invention being one day available on the
a child, Zhu remembers times with his parents, a pediatrician
and a general practitioner physician.
“My parents would talk about medical things at
dinner,” he says. “They would take me to the hospital with them, and I began
to know their world.” Their
influence shows, as Zhu went on to Fudan University Medical
School, graduating with his medical degree in 1999.
After four years working as a resident in training at
Huashan Hospital, he traveled to the United States to undertake
postdoctoral work at the University of California, San
he is in the bioengineering program at Berkeley and San
Francisco, and he hopes to obtain his Ph.D. by 2009.