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Frontiers in cytochemistry. The physical and chemical organization of the cytoplasm. Edited by Normand L. Hoerr. The Jacques Cattell Press Lancaster Pa. 1943

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HOERR. The Jacques Cattell Press, Lancaster, Pa., 1943.
This volume consists chiefly of a series of thirteen papers contributed to a
Symposium held in the University of Chicago on November 13, 1942, in honour
of Prof. R. R Bensley, the occasion being his seventy-fifth birthday. During the
10 years that had elapsed since his “retirement ” in 1932, Dr. Bensley had greatly
extended his work in cytochemistry, both through his own researches and those
of his associates, with results which had widely influenced investigators in this
field. The papers form a n impressive tribute to the significance, thoroughness
and originality of his work. They have been edited by his former associate, Dr.
Normand L. Hoerr (now of Western Reserve University), who in a brief “Forew o r d ” describes the general course of Dr. Bensley ’s researches, extending over
a period of more than 50 years, and rich in independent and fruitful contributions. The “Foreword” is followed by a n “Appreciation” by Dr. E. V. Cowdry,
the accuracy of which will be acknowledged by all who have had the privilege of
knowing Dr. Bensley or of working with him. A general review by Dr. Bensley,
“The Chemistry of Cytoplasm” (first published in Science of October 30, 1942),
forms a fitting conclusion to the volume. There is also a photograph showing
Dr. Bensley in his laboratory.
All the papers are biochemical or biophysical and their scope is best indicated
by their titles and the names of their authors. These are as follows: “The
Chemical Structure of Cytoplasm as Investigated in Professor Bensley ’s Laboratory during the Past Ten Years,” by Arnold Lazarow; “Some Considerations
on the Application of Biological Oxidation-Reduction Systems to the Study of
Cellular Respiration,” by E. S. Guzman Barron ; “ Ultracentrifugal Studies on
Cytoplasmic Components and Inclusions, ” by H. W. Beams ; “Electrolytic Solutions Compatible with the Maintenance of Protoplasmic Structures, ” by Robert
Chambers ; “ Distribution of Nucleic Acids in the Cell and the Morphological
Constitution of Cytoplasm, ” by Albert Claude ; “ Experimental Epidermal
Methylcholanthrene Carcinogenesis in Mice, ’’ by E . V. Cowdry ; “Histochemical
Analysis of Changes in Rhesus Motoneurons after Root Section,” by Isidor
Gersh and David Bodian ; “Methods of Isolation of Morphological Constituents
of the Liver Cell,” by Normand L. Hoerr; “Electrolytes in the Cytoplasm,’’ by
Oliver H. Lowry; “Fibrous Nucleoproteins of Chromatin,” by A. E. Mirsky and
A. W. Pollister; “The IJltrastrncture of Protoplasmic Fibrils,” by Francis 0.
Schmitt, Cecil E. Hall and Marie A. .Takus; “Mineral Distribution in the Cytoplasm,” by Gordon €1. Scott, “ Studies on Macromolecular Particles Endowed
with Specific Biological Activity,” by Kurt G. Stern.
T t is not possible to describe here in any detail the highly varied and interesting
(Iontent of these papers and the rcviewr will confine himself to a brief consideration of some of the more significant observations and certain general conclusions
derived from them. Briefly, thp problem of cytochemistry may be defined as (1)
how to i d a t e for aiialysih th(1 esseiiyial chemical arid structural components of
the living cell, and ( 2 ) to indicate how these are combined in the actual organization and activity of the cell. I n the work of analysis mechanical, optical and
chemical methods are used. Evidently any reliable michrochemical analysis requires that the original composition and distribution of the cellular components
should be altered as little as possible; and the method of low temperature dehydration (greatly improved in Dr. Bensley ’s laboratory and discussed in Hoerr’s
paper) has been extensively used in these studies as the best means to this end.
This method is combined with microincineration in Scott’s study of the distribution of mineral constituents in cells. Various compounds, especially proteins, are
iholated or dift’erentiated by taking advantage of their differential solubility in
salt solutions. The relations of particles and other structural elements (mitochondria. Golgi apparatus) to the normal cell-structure as well as the molecular
and rnicellar size of various components are investigated by the ultracentrifugal
technique (Beams, Claude, Stern). Ultraviolet absorption is used in the localization of nucleic acid (Gersh and Bodian). The comparative rates of electrophoresis are also used to differentiate colloidal components (Stern). Mechanical
trituration at low temperature forms a n important part of the mpthod for the
isolation of plasmosin and other nucleoproteins (Lazarow, Hoerr, Stern). IJltrasonic vibrations are used for disintegration in some cases, e.g., Streptococcus
pyogenes (p. 311).
I n several papers the distribution and physiological significance of inorganic
salts are considered in some detail (Chambers, Lowry, Scott ; also in Cowdry’s
stiidy of epidermal carcinogenesis). The relation of fibrous proteins to cellular
structure is studied with the electron microscope in the work of Schmitt, Hall
and Jakus, and with histochemical methods by Hoerr and by Stern. Special
interest attaches to the studies on the distrihiition and r61e of nucleoproteins
(papers by Lazarow, Claude, Hoerr, Mirslrp and Pollister, Stern). Mention
should also be made of the close associations found analytically between proteins
and lipins (especially phosphatides) , as indicating the fundamental importance
of the latter compounds in cellular structure. On the metabolic side special
attention should be drawn to Barron ’s excellent review of the relations between
oxidation-reduction systems and cellular respiration. Since the free energy for
cellular activity - including the energy underlying. the synthesis and maintenance of cell organization - is derived chiefly from oxidations catalyzed by these
systems, their fundamental biological significance is evident. Barron points out
that in the living c~elltheir activity is controlled by their relations to cell structure ; for exampltl, ground tissues are unable to carry out reactions catalyzed by
pyridine nucleotides, while tissue slices of the same organ readily do so (p. 63).
The synthetic reactions of the rell, which typically require oxygen, are especially
dependent on intact striictiire.’
Mirskp and Pollister tlifler fro m IIoerr with regard to the presence of fibrous
niicleoprotein imhich includes plasmosin) in the cytoplasm of the liver cell. They
call attention to the fact that in general the proportion of nncleoprotein extractable from cells increahes a s tht1 relative nuclear volume increases; they also point
ont that the Feiilgen reaction. indicating desoxprihose nucleic acid, is typically not
given by the cytoplasm ; their conclusion is that nucleoproteins are essentially
confined to th(h rcll nuclei. The genrral physiological importance of the nucleo‘The sFmhol f o r nntnr:rl Iogarithm. In, is misprinted as I n in thr formiilar on pages 47 and 56
proteins is evident : the authors ask, “can we find in nucleohistone the chemical
basis for heredity ? ” Hoerr maintains that nucleoprotein is also present in important quantity in the cytoplasm (p. 227). To the reviewer the evidence seems
to indicate that while these compounds are present chiefly in the nuclei -and
undoubtedly are chiefly synthesized there -their
presence in the cytoplasm
cannot be altogether excluded. The known dependence of the general cellular
metabolism on the nucleus, as shown by the disorganization following enucleation
in all types of cell, is itself a n indication of their presence in the cytoplasm.
Many cells contain extranuclear structural elements or particles which consist largely of nucleoprotein (Nissl bodies, mitochondria, certain granules) ; there
is also the fact from pathology that viruses (which are known to be nucleoprotein)
multiply in the cytoplasm of the infected cells. The relation of nucleic acid to
synthetic metabolism is clearly an intimate one ; recently the addition of nucleoprotein to tissue cultures has been shown t o promote proliferation in many cases
(cited by Stern, p. 310). The central position of this material in the cell, a universal feature of cellular organization, seems to indicate a special relation to
growth and synthesis, although the precise nature of this relation is not understood at present. While the multiplication of nucleotides appears to occur chiefly
in the nuclear area, the cabe of virnscs shows that it may also occur in the cytoplasm. The typical separation of the nuclear material from the cytoplasm by a
membrane is a significant fact, but this separation is periodically interrupted
during the multiplication of cells by mitosis; the association of mitosis with
rapid cell growth and development seems to imply a catalytic relation of the
nuclear proteins to the cytoplasmic syntheses. Gersh and Bodian show that the
chromatolysis of Nissl bodies following axone section is a reversible process; and
on the basis of their observations with ultraviolet absorption, as well as with
ribonuclease, they are inclined to localize the resynthesis in the cytoplasm. They
also cite evidence from tracer studies of Schoenheimer indicating that the ribonucleic acid in cells is in a continual state of flux (p. 182). A definite level of
dynamic equilibrium appears to be characteristic of each type of cell ; the reversal
of the changes in nncleogrotein metabolism is an illustration of a general condition common to all forms of living matter. Synthetic reactions of many kinds are
continual in the cell during life, and cease a t death; it is well known that the
multiplication of viruses requires the presence of these bodies in the protoplasm
of living cells, and what is true for the synthesis of these foreign proteins is obviously true also for the synthesis of the proteins and other metabolizing compounds normally present in the cell. One cannot speak of the viruses any more
than of these compounds as independently “living. ”
I n conclusion the reviewer cannot resist quoting Dr. Bensley ’s final paragraph
(p. 333) : “It is a pleasure also t o reflect that the funds a t my disposal have
never been large enough to tempt me to abandon investigation for the direction
of others, and thus to miss in these years of retirement the joys that come, in
fullest measure, only t o those who satisfy their desire f o r knowledge by a direct
and personal appeal to nature by research. ”
University of Chicago
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physical, cytochemistry, cattell, hoerl, norman, lancaster, jacques, cytoplasmic, chemical, 1943, edited, frontiers, organization, pres
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