X-Message-Number: 12178
Date: Fri, 23 Jul 1999 09:34:17 -0700 (PDT)
From: Doug Skrecky <>
Subject: increasing resistance to dehydration

Authors
  Gilles R.  Bourdouxhe-Housiaux C.  Colson P.  Houssier C.
Institution
  Laboratory of Animal Physiology, University of Liege, Belgium.
  
Title
  Effect of compensatory
  organic osmolytes on resistance to freeze-drying of L929
  cells and of their isolated chromatin.
Source
  Comparative Biochemistry & Physiology. Part A, Molecular & Integrative
  Physiology.  122(1):145-55, 1999 Jan.
Abstract
  (1) Compensatory organic osmolytes are
  stabilizers of macromolecular structures. During acclimation to dehydration
  or high salinity, they accumulate in cells and effectively
  protect them against disruption that might otherwise result from increased
  inorganic ion concentrations. (2) Circular and electric
  dichroism, analysis of the kinetics of digestion by micrococcal nuclease, and
  UV spectra between 190 and 305 nm were used to investigate the resistance to
  dehydration upon freezing or freeze-drying that could confer such compounds
  to chromatin isolated from cultured L929 cells. Some work was also done on
  intact cells in vivo. (3) Sorbitol, sucrose, and trehalose appear to protect
  isolated chromatin very effectively; proline is less
  effective. (4) These compounds also
  effectively protect chromatin from the disrupting
  effects of NaCl. (5) Cells loaded and grown with sorbitol,
  sucrose, or proline can tolerate larger decreases in hydration than control
  cells. They cannot, however, tolerate complete dehydration.

  Additional comment by poster: 

    Further work by this team is apparently in progress testing the
  effect of other polyols on increasing dehydration resistance. This
  may have some implications for cryonics as with sufficient dehydration
  freezing would result in vitrification.

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