Evening star., 1942-08-29
Of Stors, Men
And Atoms
Notebook of Science PROGRESS
In Laboratory. Field
And Study
By Thomas e. Henru,

There is an age clock by which mans
days are Numbered.
Its hands move at a predestined rate
from birth to death-but very few in
oividuals actually live long enough for
these hands to circle the dial.
They die of damage to the physiologi-
cal system which has little Or nothing to
do with these inexorably moving indlca-
tors
Such Is the concept of DR.. Anton J.
Carlson, professor of physiology at the
University OF Chicago. who is playing a
leading role in the development of medl-
cine's newest specialty-the science of
aging.
The speed OF the clock is determined
largely by the heredity of the individual
DR.. Carlson holds. Nothing can be done
about it except by altering this heredlty.
q task at present beyond the prospects OF
science. But great deal can be done
he believes, by isolating the age changes
that form part of this mechanism from
those due to faulty living which can be
treated or prevented by physicians.
Progressive age changes not yet shown
to be due to specific disease or accident,
and which might be considered as the
hands of the clock, are listed by DR.,
Carlson:
A gradual drying up of body tissues.
gradual retardation of cell division
so that injuries are repaired by new
growth less rapidly. This. he points out,
is strikingly illustrated by recent deter
mlnatlons Of the rate of healing OF skin
wounds. Such an injury 40 centimeters
square in a person of 20 heals on an
average in 40 days. In a person of 40
about 80 days are required for the same
process. At the age of so such a wound
requires five times longer to heal than In
a child of 10.
Gradual retardation in the rate of
tissue consumption of oxygen. Life itself
might be considered a slow fire with each
cell burning sugars and starches through
combination with oxygen
Increased cell fermentation and fatty
inflltration which may be major fac
tor in the progressive hardening of the
arteries. There is some evidence. how
ever, that this process may be greatly
influenced by newly discovered hor-
none which is formed in the pancreas.
Gradual decrease in tissue elasticity
and eegenerative changes in elastic con-
nective tissue. Owing to this decrease
in elasticity as it effects the arteries, DR..
Carlson points out, there is a gradual
increase in the speed of propagation of
second at the age of 20 to eight meters
second at so.
Progressive degeneration and atrophy
OF the nervous system impaired vision,
hearing. attention. memory and mental
endurance. Notable are the changes in
the lens of the eye which come to nearly
every one at middle age. 1t actually starts
in childhood, DR.. Carlson says, and prac-
ticaliy all elasticity of the lens is lost
at so.
AL these changes, he points out, nat
urally can be increased above their nor
NAL rate by environmental factors, such
as infections, unwise diet, etc. But there
Is little hope that they can be slowed
down below a hereditarily determined
rate.
With few exceptions, DR.. Carlson says,
all the changes in the machinery of the
body which parallel the aging process
point to a gradual depletion of the hered-
itary tissue reserves or factors OF safe
ty,' so that the aging individual grad
ually becomes less able to meet the usual
accidents and the unusual stresses of
living
DR.. Carlson is adviser to the National
Institute of Health which now is seeking
to map out the problem of prolonging
the life span of the individual beyond
the dangerous middle wears.