33.06
years
Life expectancy
at age 50 for u.s.
women, 2007
31.95
years
Life expectancy at
age 50 for Danish
women, 2007
37.26
years
Life expectancy at
age 50 for Japanese
women, 2007
Cells build blood vessels for surgery
New technology could prove useful in bypasses and dialysis
By Nathan Seppa
Using human cells as tiny factories,
researchers can grow new blood vessels
that might someday provide a valuable
option for patients undergoing surgery
for kidney dialysis or a heart bypass. A
new study testing the bioengineered
vessels in baboons and dogs raises the
prospect of mass-producing such natural-tissue vessels, researchers report in the
Feb. 2 Science Translational Medicine.
In coronary bypass surgery, a vein is
typically stripped out of a part of the
body that can manage without it and
implanted on the heart as a conduit supplying blood to the heart muscle. But in
some patients, vessels are inaccessible
due to obesity, deterioration or having
been used up in other operations. Those
individuals have few alternatives beyond
medication, says study coauthor Alan
Kypson, a surgeon at East Carolina University School of Medicine in Greenville,
N. C. “A blood vessel that comes right off
the shelf for a bypass — that’s potentially
Coaxed by scientists, human cells built
this bioengineered blood vessel. It could
one day be implanted in kidney patients.
groundbreaking stuff,” he says.
The first population to benefit from
these bioengineered vessels would prob-
ably be kidney failure patients who need
to undergo dialysis, in which the blood is
cleansed every few days. Dialysis needs
fast blood flow to work well, so a patient’s
best option is surgery to join a large artery
directly to a vein to create a circulatory
shortcut. But many patients have ves-
sels unfit for that surgery or the surgery
does not succeed; those people often get
implanted with a synthetic vessel to join
an artery and vein. Both operations, typi-
cally done in an arm, carry risks of infec-
tion and clogging from a buildup of cells.
Flu vaccine not
linked to illness
No connection with Guillain-
Barré found in Chinese data
By Nathan Seppa
Courtesy of Science/AAAs
Speculation drawing a link between
H1N1 flu vaccination and the risk of a rare
neuromuscular disorder has been dashed
by a huge study. An analysis of side effects
among nearly 90 million people in China
vaccinated during the 2009–2010 flu
season found that only 11 were subsequently diagnosed with Guillain-Barré
syndrome, a rate no greater than what
normally appears in the population. The
study appears online February 2 in the
New England Journal of Medicine.
In 1976, a strain of swine flu in the
United States prompted the manufacture and delivery of more than 40 million doses of vaccine. An epidemic never
materialized, but hundreds of Guillain-Barré syndrome cases were reported after
the vaccination campaign. The vaccine
was withdrawn. In 2003, the Institute of
Medicine found that the data pointed to
an association between the 1976 vaccine
and the syndrome. IOM found no clear
evidence of such a link with subsequent
flu vaccines, but some concerns have lingered vis-à-vis flu vaccination.
These fears intensified in 2009 when
another swine flu emerged, this time
known as the H1N1 flu, and a vaccine
was made for it. After mass vaccinations,
physician Yu Wang and colleagues at the
Chinese Centers for Disease Control and
Prevention in Beijing collected data on all
adverse effects reported by 89.6 million
people in China who received the flu vac-
cine in 2009 and 2010. The researchers
found an exceptionally low rate of Guil-
lain-Barré syndrome among those who
had been vaccinated — less than the back-
ground rate in the population.
