X-Message-Number: 13612
Date: Fri, 21 Apr 2000 09:57:31 -0400
From: "J. Hughes" <>
Subject: Blood Substitute and Freezing Experiment

Ice-Cold Blood-Substituted Dogs and Hamsters Revived After Prolonged
Periods of Clinical Death; Results May Hold Clues to Protecting the Brain 
 
Updated 12:23 PM ET April 17, 2000 

Current quotes (delayed 20 mins.) BTX  9 1/4  0  (0.00%)  
   
BERKELEY, Calif. (BW HealthWire) - BioTime, Inc. (AMEX:BTX) announced today
that a team of its research scientists directed by Dr. Hal Sternberg,
BioTime research vice president, revived five hamsters following extended
periods of cardiac and circulatory arrest. The results will be reported at
Fluid Resuscitation 2000, a conference to be held on May 31-June 2, 2000 in
Galveston, Texas, by BioTime scientist Cornelia Gramlich.

The hamsters were anesthetized, chilled and completely blood substituted
with modified forms of Hextend, BioTime's proprietary physiologically
balanced plasma volume expander currently used in the US to treat blood
volume loss during surgery. They were then further cooled to near-freezing,
their hearts were arrested and they were maintained without heartbeat or
circulation for 4-5 hours. The animals were then warmed, transfused and
revived to consciousness.

Previous experiments conducted by Dr. Sternberg indicated anecdotally that
hamsters could be revived after 4-6 hours of hypothermic blood substitution
and cardiac and circulatory arrest. However, the latest work used a
patentable combination of BioTime's proprietary devices, solutions and
protocols to allow a more consistent and repeatable result. An important
factor in obtaining these results involved lowering CO2 levels in the
blood, and presumably also in the brain, before deep chilling and the
induction of circulatory arrest.

Using a related approach, BioTime scientists and their collaborators have
been able to fully revive dogs blood-substituted with a modified Hextend
solution and chilled to near-freezing. In a series of experiments to be
reported on at a scientific conference this week, five out of six dogs
reviving after 2 hours of hypothermic circulatory arrest are currently
alive and well. As in the hamster experiments, low blood levels of CO2
prior to cooling were also associated with good outcomes. Dr. George V.
Letsou of the Department of Surgery, University of Texas Health Science
Center, Houston, TX, will present the work on Tuesday, April 18, 2000, at a
session of Experimental Biology 2000, a scientific convention taking place
this week in San Diego, California.

"BioTime's unique devices, solutions and techniques have allowed us to gain
a basic understanding of some of the important factors in maintaining
subjects at low temperatures for extended time periods," said Dr.
Sternberg. "This understanding is critical in designing technology to allow
prolonged surgeries on the heart and brain in which circulation is
interrupted, to facilitate rescue in severe trauma situations, and to
prolong the period that organs can be stored prior to transplantation."

"In addition, understanding the mechanism of delaying brain death at low
temperatures will facilitate an understanding of how to best treat the lack
of blood flow to the brain that can occur at normal temperatures during
heart disease and trauma, brain pathology resulting from suffocation,
drowning, stroke and other causes."

BioTime is in the process of finalizing an amendment to its IND for
Hextend, in order to study the use of this plasma expander in low
temperature medicine.

BioTime, headquartered in Berkeley, California, is engaged in the research
and development of blood plasma volume expanders, blood replacement
solutions during hypothermic (low temperature) surgery, organ preservation
solutions and technology for use in surgery, emergency trauma treatment,
the preservation of organs awaiting transplant, and other applications.
Information about BioTime can be found on the web at www.biotimeinc.com.

The matters discussed in this press release include forward-looking
statements which are subject to various risks, uncertainties and other
factors that could cause actual results to differ materially from the
results anticipated. Such risks and uncertainties include but are not
limited to the results of clinical trials of BioTime products; BioTime's
ability to obtain FDA and foreign regulatory approval to market its
products; competition from products manufactured and sold or being
developed by other companies; the price of and demand for BioTime's
products; BioTime's ability to negotiate favorable licensing or other
manufacturing and marketing agreements for its products; the availability
of ingredients used in BioTime products; and the availability of
reimbursement for the cost of BioTime products (and related treatment) from
government health administration authorities, private health coverage
insurers and other organizations. These and other risk factors are
discussed in BioTime's Annual Report on Form 10-K filed with the Securities
and Exchange Commission. 

Contact: BioTime, Inc. Victoria Bellport, 510/845-9535 

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