*_Calcium?s possible role in Alzheimer?s_*
By Patrick BarryWeb edition : Wednesday, July 30th, 2008
A new study in mice finds that plaques associated with Alzheimer?s wreak
havoc on calcium?s role in cell signaling.
Careful journalists write that Alzheimer?s disease is associated with
the characteristic plaques in patients? brains, never that it?s caused
by those plaques.
Scientists have been uncertain whether these plaques actually cause the
memory impairment typical of the disease, but new research on mice
suggests that calcium could link the plaques to nerve-cell dysfunction.
?It?s the first evidence that calcium can be affected by [plaques] in
areas that are important for synapse formation and learning and memory,?
comments Alzheimer?s disease expert Kim Green of the University of
California, Irvine, who cowrote a review article published with the new
research in the July 31 Neuron.
?Apparently the calcium is playing a very, very important role,?
comments Bharat Aggarwal, an expert in cell signaling and inflammation
at the University of Texas M.D. Anderson Cancer Center in Houston. The
research ?provides us more targets for finding treatments for the disease.?
Calcium ions, positively charged calcium atoms, relay signals that
control many functions within cells and between neighboring cells.
Previous research suggested that calcium might be involved in
Alzheimer?s disease, but scientists didn?t have any evidence from living
In the new experiments, Brian Bacskai and his colleagues at
Massachusetts General Hospital in Charlestown, Mass. compared two kinds
of mice having Alzheimer?s-like conditions to healthy mice. Calcium in
the brains of healthy mice was tightly controlled, but plaques in
diseased mice elevated the levels of calcium in nerve cells, Bacskai?s
team found. Nerve cells closest to the plaques were the most affected.
The researchers also looked at the effects of this calcium imbalance on
the cells? functioning. High calcium levels caused the ?wires? between
neurons to become malformed, the scientists report.
?The neuron is still alive, it?s just not communicating effectively,
which could lead to the cognitive impairment,? Green says.
Abnormal calcium levels might also disrupt the creation of synapses, the
tiny gaps across which neuron wires communicate. Forming new synapses is
one way that scientists think neurons store new memories.
?There?s little doubt that calcium can change what synapses can do,?
comments George Augustine, an expert on calcium signaling in neurons at
Duke University Medical Center in Durham, N.C.
However, the new research does not show how the plaques raise calcium
levels in the nearby neurons. And scientists don't yet know whether this
calcium link in mouse brains also exists in people with the disease.
Mobile Communications Featured Article
August 14, 2008
EMRPI and IBEW Oppose Alltel / Verizon Wireless (VZW) Merger
By Anuradha Shukla
TMCnet Contributing Editor
EMR Policy Institute (EMRPI) is formally opposing the Alltel (News
<http://www.tmcnet.com/snapshots/snapshots.aspx?Company=Alltel> - Alert
<http://www.tmcnet.com/enews/subs.aspx?k1=%22Alltel%22>) / VWZ merger by
filing a Petition to Deny at the Federal Communications Commission
(FCC), which sets the policy for RFR exposure to all workers who come in
contact with antennas in their workplaces. The petition says that FCC
(News <http://www.tmcnet.com/snapshots/snapshots.aspx?Company=FCC> -
has not addressed the impact of long-term exposure to RF radiation (RFR)
on human health as mandated by the National Environmental Policy Act (NEPA).
Under the law, regardless of employment category, all mobile carriers
have a non-transferable FCC license requirement to protect workers from
RFR harm. Workers who install and repair mobile phone antennas are
required to be trained and alerted to dangerous RFR levels. In contrast,
third-party workers are left ignorant and defenseless in the wireless
workplace. EMRPI officials believe that job site workers are quite
likely to be in a direct line with the antennas' RF beams and get
exposed to RFR at levels 200 times stronger than holding a cell phone to
EMRPI officials emphasize that there is a double standard for worker
protection in FCC's RFR safety guidelines. According to the FCC policy,
workers who work directly with antenna equipment must have specific
training and protection equipment. The officials point out that no
equivalent training is provided for construction and maintenance workers
or for painters and window washers whose bodies come in close contact to
antennas on the sides of buildings. In fact, even firefighters don?t
know if the antennas they encounter at fire sites are emitting RFR.
EMRPI President, Janet Newton, said that currently FCC policy leaves
thousands of workers unprotected. Their petition opposes the Alltel /
VZW merger until VZW implements an RFR safety solution that protects all
categories of workers near VZW's antenna sites.
The International Brotherhood of Electrical Workers (IBEW) has also
filed comment protesting the Alltel / VZW merger on worker safety
grounds. IBEW represents nearly 750,000 workers in every state in fields
including utilities, construction, telecommunications, broadcasting,
manufacturing, railroads and government. According to IBEW, if FCC
approves the merger, it should grant the applications subject to the
condition that the merged company immediately adopt a nation-wide RF
safety system that protects all workers.
Officials added that the risk for the workers is multiplied when antenna
sites are camouflaged and despite this fact the municipalities continue
demanding stealthing of antennas from public view as it supports the
public's desire not to see antenna.
?EMRPI opposes the Alltel / VZW merger until FCC updates it RFR safety
requirements to protect all workers and the public,? stated Newton.
/Don't forget to check out TMCnet?s White Paper Library
<http://www.tmcnet.com/tmc/whitepapers/>, which provides a selection of
in-depth information on relevant topics affecting the IP Communications
industry. The library offers white papers, case studies and other
documents which are free to registered users./
/Anuradha Shukla is a contributing editor for TMCnet. To read more of
Anuradha?s article, please visit her columnist page