X-Message-Number: 10714
Date: Sat, 07 Nov 1998 06:53:37 -0800
From: Peter Merel <>
Subject: Guns and Trehalose

On Guns:

What does it matter how you die? What matters is how likely it is that you
will die. Look at average lifespan in the US and elsewhere, factor in the
imminence of y2k and its likely effects on your risk, consider the differences
that socioeconomic status makes, and do what you can to reduce your own
personal troubles. Then pay your money and take your chances. 

The risk of getting shot is almost irrelevant to average lifespan here, and
certainly don't factor into cryonic concerns; if you get stored in a dewar 
in the US, and don't like what you see if you are lucky enough to get revived,
then move away to wherever else you think is better.

As to questions about whether or not you want your government to prevent
your neighbours from being armed, that's a religious issue that can only
cause friction here. Some people are irrationally afraid of guns. Some
are irrationally fond of guns. Most of us simply have more pressing
concerns. Let's get back to signal.

On Trehalose:

I was surprised no one else picked up on this. From New Scientist magazine,
November 7:

"Taking a tip from tiny animals that can live for more than a century, 
Japanese researchers have invented a new technique for storing human organs 
for transplant. 

The team, which has successfully revived a rat's heart after 10 days in
storage, says the work may lead to organ banks similar to blood banks. 
These would allow doctors to avoid the frantic dash to bring suitable 
organs straight from donors to the operating table. 

Organs can usually be stored for only 30 hours before they have to be used. 
For hearts and lungs, the time limit is even less--just 4 hours. The main
problem with keeping organs in cold storage is that water damages cell 
membranes at low temperatures. Unfortunately, removing water from tissues 
usually causes at least as much damage. 

But Kunihiro Seki and his colleagues at Kanagawa University in Hiratsuka-shi, 

Japan, knew that animals called tardigrades can withstand extreme conditions by

losing most of the water in their bodies (In Brief, 31 October, p 26). They can
survive in this state for a century or more. When water was added to a dried-
out moss kept in a museum for 120 years, tardigrades were later found crawling 
all over it. 

To achieve this feat, tardigrades use a sugar called trehalose to stabilise the
structure of their cell membranes. "This suggested that the physiological 

mechanism for preservation and resuscitation of tardigrades could be applied to
the preservation of mammalian organs," says Seki. 

To test this, the team flushed rat hearts with trehalose solution before 
packing them in silica gel to remove the water from their cells. The hearts 
were then immersed in perfluorocarbon, a biologically inert compound, and 
stored at 4  C in airtight jars. Ten days later, the team took the hearts out 
of the jars and resuscitated them. Within half an hour, they were beating 

again. Measurements of their electrical activity suggested that the heart cells
had survived intact. 

Seki believes that the trehalose and perfluorocarbon replace the water in the 
cells, preventing tissue damage. He plans to repeat the experiment with a 
complete autopsy to confirm that the tissues are preserved intact. The 

researchers also plan to demonstrate the procedure with other animal organs and
prolong their storage for up to a year. Seki hopes that within a few years the 
technique could be used to preserve human organs. 

"The implications for transplant patients would be huge," comments Vanessa 
Morgan, who chairs the UK Transplant Co-ordinators Association. "It could lead 
to planned, elective operations rather than emergency surgery." She adds that 

recipients could have a greater choice of donor organs, improving their chances

of a good match. But she cautions that the quality of transplant organs must be
maintained during long-term storage. "The condition of organs is crucial and I 
wouldn't want to compromise condition for time." 

Looking forward to Sunday's 21CM conference,
Peter Merel.

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