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NEWS OF THE WEEK
Inhaled multiwalled carbon nanotubes (shown expanded) travel to and become embedded in the pleural tissue (left) and are encapsulated by phagocytes (right).
* 50 nnii . mm
NANOTUBES SCAR MOUSE LUNGS
toxicologists are particularly concerned with the pleural region because the rare cancer mesothelioma, which is frequently associated with asbestos exposure, develops there. Scientists have expressed concern that nanotubes
NANOTOXICOLOGY: Inhalation of carbon structures causes
unique physiological effects
maybehave like asbestos because oftheir fiberlike shape. To see how far multiwalled carbon nanotubes travel
when inhaled, Bonner's team subjected mice to a single inhalation exposure to the tubes at a concentration
of30 mg/m3. They then collected lung tissue after one
day, as well as two, six, and 14 weeks after exposure.
F INHALED, multiwalled carbon nanotubes can
The researchers found that the nanotubes traveled to
Itravel to the lunglining ofmice and cause scarring,
just beneath the pleura, where scarring developed two,
according to a paperfrom James C. Bonner ofNorth
six, and 14 weeks after exposure. The team observed no
Carolina State University and coworkers (Nat. Nanotech., mesothelioma but notes that the slow-growing cancer
DOI: 10.1038Znnan0.2009.305). The results suggest extra is unlikely to show up in their experimental time frame.
caution should be exercised to
Similar experiments carried Offtwith carbon-black
avoid inhaling carbon nanotubes
nanoparticles produced no scarring.
50 nm.......
m VL
when handling the material. "This is the first published
"The take-home message is that we should be careful in the waywe handle carbon nanotubes because based
study to demonstrate that
on our mouse study, these fiberlike structures will
inhaled carbon nano reach the outer lining ofthe lung and remain there for
tubes reach" the lung weeks or months," Bonner tells C8cEN.
lining, also known as
"This is an important paper," comments nanotoxicol
the pleura, note Ken
ogy expert David B. Warheit ofthe DuPont Haskell Labo
Donaldson and Craig ratoryfor Health 8c Environmental Sciences, in Newark,
A. Poland ofthe Uni
Del. However, "the effects were manifested following
versity ofEdinburgh's an extremelyhigh exposure concentration ofcarbon
Center for Inflamma nanotubes," he adds. "It will be important to ascertain
tion Research, in Scotland, in a commen whether the observed potency occurs at relevant occu
tary that accompanies the paper. Nano
pational exposure levels."-- BETHANY HALFORD
EMERGENCY DRUG FILLS VACCINE VOID
are being supported by $180 million in Department of Health 8c Human Services (HHS) funding. BioCryst's partner, Shionogi, has completed late-stage studies in Japan and is filing for approval there.
PANDEMIC: FDA allows use of unapproved flu drug while vaccine supplies lag
"BioCryst has worked with HHS to enable the gov ernment to rapidly deploy an initial supply ofperami vir, and we are prepared to deliver more," says the firm's CEO, Jon P. Stonehouse. The company already
has provided HHS with 1,200 courses oftreatment,
each consisting of600 mg per day for five days.
ELIEVING THAT the possible benefit outweighs
In preparation for orders from the U.S. or other gov
Bany risk, FDA is allowing BioCryst Pharmaceu
ernments, BioCryst is completing production ofabout
ticals' unapproved drug peramivir to be used in
130,000 more treatment courses. According to analysts
treating hospitalized flu patients. The new antiviral at the investment firm Leerink Swann, this could trans
agent has been made available to battle the novel H1N1 late into about $39 million in sales for the company.
influenza virus at a time when vaccines are overdue.
Under the emergency use authorization, BioCryst is
Just about a week ago, FDA issued an emergency use not allowed to promote its drug. CDC will control how
authorization for peramivir, following a request from
and where peramivir is distributed.
the Centers for Disease Control 8c Prevention (CDC).
Meanwhile, producers ofH1N1 vaccines continue
With no adequate approved alternative, FDA says, the
to have difficulty supplying as many doses as they once
drug is meant for patients who aren't responding to or promised. As of Oct. 28, about 23.2 million doses were
can't take Roche's oral drug Tamiflu or GlaxoSmith
available, HHS Secretary Kathleen Sebelius said in a
Kline's inhaled product Relenza.
press briefing. Although the number ofdoses grew
Discovered by Birmingham, Ala.-based BioCryst,
by about 9 million in one week, it is much below the
peramivir inhibits neuraminidase, an enzyme that is
45 million doses that were anticipated to be on hand
critical to the replication ofthe flu virus. In the U.S., the by mid-October and the total of250 million doses re
company has the drug in Phase III clinical trials, which served under contracts.--ANN THAYER
If)WWW.CEN-ONLINE.ORG
NOVEMBER 2, 2009