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Scientists Uncover Cause of AIDS Related Dementia
corazonesunidosvihsida.org
Report.
Posted:
April 21, 2004 2:20 p.m. ET
(New
York City) Researchers have uncovered an HIV/AIDS mystery that
affects
about a quarter of the people infected with the disease.
Scientists
at Philadelphia's Thomas Jefferson University,
Philadelphia
have discovered that the virus produces proteins that
cause
brain cells to die.
For
twenty years doctors have been trying to determine why so many
people
develop AIDS Related Dementia, and why there are not warning
signs
it is coming on.
Unlike
other brain infections such as meningitis and herpes, HIV
causes
hardly any brain inflammation or white blood cell increase.
The
Thomas Jefferson team has found that HIV causes neurons - or
nerve
cells - to die, leading to wastage of the brain.
This
is "extremely unusual" and different to other infectious
agents,
according to Dr Roger Pomerantz, at Jefferson Medical
College.
The
theory has previously been that HIV infects brain cells called
macrophages
and miroglia, which then produce cytokines and
chemokines,
killing neurons.
Dr
Pomerantz's team tested whether the virus itself caused the nerve
cells
to die, or whether this was caused by substances produced by
infected
cells.
They
looked at brain cells and T-lymphocyte blood cells, taking the
virus
out of some of them and leaving it in others. When applied to
the
nerve cells, they found they were killed when the virus and its
proteins
were present.
"When
we looked at T-cells, the only thing that killed neurons was
the
virus," Pomerantz said..
"Once
the virus is removed, nothing from the T-cells would kill
neurons."
After
investigating the neurons themselves, they found two well-
defined
pathways to cell death, which were activated by proteins
from
the virus.
Dr
Pomerantz said: "We feel that it is mainly the virus and viral
proteins
causing the neuronal cell death, and may now know the
precise
pathways involved."
This
would allow the development of treatments which prevent the
virus
damaging the neurons, he said.
Dr
Pomerantz's research appears in the Proceedings of the National
Academy
of Sciences.
©corazonesunidosvihsidaorg®
2004
This story
has been published with the permission of the author and can be found online at http://www.gaymarriagelawyers.com
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