X-Message-Number: 5404
From:
Date: Tue, 12 Dec 1995 03:43:25 -0800 (PST)
Subject: Trans Time Newsletter SCI.CRYONICS
THE TRANS TIMES
Life Extension through Cryonic Suspension
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Volume 4 Number 6 December 1995
Recovery of Alert Behavior after
Partial Freezing of Hamsters
by Lee McCook
The following is a brief report of a series of cryobiology
experiments conducted at BioTime, Inc. this past summer. Although
this writer's role in the research is finished for now, other UC
Berkeley students, under the direction of Hal Sternberg, are
continuing the work herein reported. A Japanese film crew from
Asahi TV filmed one of these experiments in August, and it is
hoped this may generate some support for the research effort, as
the program has been aired on a national broadcast in Japan.
The aim of the experiments was to determine whether, and to what
extent, partially frozen hamsters could be revived after having
their blood replaced with a cryoprotective solution. The work of
Audrey Smith in the 1950s had already shown that hamsters could
be revived after partial freezing, and her exhaustively thorough
experiments demonstrated the limits of time and temperature from
which these animals could be recovered without blood
substitution. She further noted that by feeding the animals some
glycerol, the odds of revival improved slightly. However, she
lacked the surgical techniques and solutions necessary to blood-
substitute the animals, and so the amount of cryoprotectant
deliverable to the animals prior to freezing was quite limited.
With the blood substitution technology developed by BioTime, it
was thought that much higher levels of cryoprotectant could be
delivered to the animal's tissues, and a series of experiments
was begun to determine: first, the magnitude of cryoprotection
the animals could tolerate without being frozen; and second, the
extent of freezing from which they could recover after being
cryoprotected.
We found that the hamster could tolerate being blood-substituted
with a relatively high molarity cryoprotectant formulation of
BioTime's plasma replacement product. They recovered from one to
two hours of circulatory arrest at the ice point sufficiently to
regain breathing, voluntary movement, alertness and
responsiveness. Using this cryoprotectant concentration, the
hamsters typically survived for several hours. No animals
survived long-term, probably due to the deleterious effects of
such a high molarity solution on epithelial membranes, especially
in the lungs. Maintaining the animals in a hyperbaric oxygen
chamber after the procedure may increase the long-term
survivability.
Having determined that this solution was tolerable for immediate
recovery, we then began freezing the animals in an ethylene
glycol bath set at,-10 degrees C, for periods of from 20 to 45
minutes, and found that the animals could be revived, after
thawing and reperfusion with whole blood, following 30 minutes of
freezing. All animals recovered to the point of attempting to
breathe. Some animals could only be kept alive on a respirator,
while others began autonomous breathing and typically survived
for several hours.
At this bath temperature, 30 minutes was sufficient time to
freeze the extremities of the animal, including large portions of
the head. The core (rectal) temperature was recorded to be
several degrees subzero, and plots of rectal temperature over
time showed a distinct plateau in the cooling curve, indicating
that a considerable amount of the animal's body water was
converting to ice.
A number of these animals were autopsied to examine their brains,
and a pattern of lesions quite specific to, and characteristic
of, freezing damage was observed in all cases. It is of some
interest to see, then, that these animals can recover respiratory
function and alert, responsive behavior after having their
brains, including the brainstem (which controls respiration) at
least partially frozen.
These results are quite reproducible, and now provide us with an
assay for testing the effects of various alterations in the
experimental protocol, including modification in the
cryoprotective solution used. The extent of cryoprotection
actually achieved can now be directly ascertained by comparing
the results of future experiments to those from this summer's
protocol. For example, further increases in solution molarity,
or changes in solution composition, can be evaluated with respect
to their effect on the extent of brain freezing, as indicated by
a change in the amount of lesions observed. Any significant
decrease in the extent of these lesions will tell us that the
modification we've made has in fact diminished the tissue damage
caused by freezing, since all other aspects of the protocol will
have been kept constant. In this way, we hope to make progress
toward formulating a solution which will permit greater freezing
of tissues with less concomitant damage.
Patients Transferred
by Art Quaife, Ph.D.
We store suspension patients in insulated dewars, which are like
large thermos bottles, filled with liquid nitrogen. A significant
part of the cost of long term storage is the cost of replenishing
the nitrogen.
In the 1970s, TRANS TIME maintained its patients in two-patient
dewars. As the number of suspendees increased, we decided to try
to achieve economies of scale. John Day and I prepared
specifications and had manufactured our King Kong dewar, designed
to hold about 11 patients. Finally in 1990 we had enough patients
to place the dewar into service.
Sadly, the dewar has never performed up to our specifications,
even after efforts to pump the vacuum down further.
About this time, Alcor found that it was possible to have quite
efficient 3-patient dewars manufactured. John Day and I made a
few modifications to the design they used, and ordered one of
these Son of Kong units. The per-patient boiloff of the Son of
Kong dewar is about 30% percent of the boiloff of the King Kong
dewar.
We no longer have a contract to provide services to the American
Cryonics Society. As a consequence, a number of patients that we
formerly maintained for them were recently transferred to storage
in Southern California. All of our remaining patients (two whole-
body, two brains, and several pets) would then fit into our Son
of Kong dewar.
We carried out the patient transfers on October 29. The team
consisted of John Day, Paul Hirsch, Lee McCook, Art Quaife, and
Steve Seinberg. Steve Garan observed. We have conducted this
operation a number of times in the past, and it went without a
hitch.
[PHOTO OMMITED]
More on Consciousness
by Hal Sternberg, Ph.D.
I would like to recommend the book Elemental Mind by Nick Herbert
(published by Dutton Press, 1993), to those interested in the
subject of consciousness. It is the most intellectual,
informative and insightful book of its kind I know. As others are
postulating--see Review by James Newman in Consciousness and
Cognition 4, 172-173 (1995)--the reticular formation (RF) in the
brainstem is likely the region of integration, consciousness and
attention.
Previously, I wrote that some circuitry of the reticular
formation dictates _who_ will exist. This is who will experience
and perceive. _What_ is experienced moment to moment is dictated
by firing that influences the electromagnetic "field" created by
certain RF firing. I think that the reticular formation is the
most important part of the brain to retain intact.
My thoughts on the subject have expanded. I expect that the
electromagnetic "field" or "entity" created by a specific complex
firing pattern in the RF can sense and interact beyond its
"boundaries." I expect that activity of neurites that enter the
RF field open a gateway, so to speak, that allows the RF entity
(or identity) to interact with certain electromagnetic fields
created by cortical, hippocampal and possibly thalamic neuron
firing (of unmyelinated cells). Thus, the conscious experience
which requires RF participation may not be localized in the RF.
However the RF is necessary for any sensation or experience and
consciousness.
So in summary, the identity field created by the RF can _reach_
out or reach beyond its locality to sense and integrate other
"fields" created in the brain. The summation of interacting "
"fields" with the RF field is the conscious experience.
Nature is amazing. I was wondering what the probability might be
to exist again. I expect the probability is quite low. It also
opens the question of whether you can exist at the same time in
two separate brains. It sounds crazy but maybe it is not.
What is most amazing to me is that nature, i.e. matter and
energy, is aware of itself. Thus, the world evolved to be
manipulatable, with certain creative purpose, and not random. It
is self manipulatable.
Consciousness is a wonderful gift of nature.
I think that the attributes that make electromagnetic energy so
amazing are:
1) Its ability to interact.
2) Forces that provide it with a tendency to create discrete
forms.
Thus, we see discreteness of electromagnetic energy as in
subatomic particles, atoms, chemicals, compounds, structures,
etc. I suspect that the complex field created by RF firing has
discreteness so as to have special unique "form." Each individual
would possess a slightly different and unique electromagnetic
energy field form. Just as an atom has its own discrete
boundaries and is enabled to interact with the outside world, so
can the RF field, i.e. our identity.
[FIRST HALF OF NEWSLETTER; TO BE CONCLUDED TOMORROW]
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