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Biology of bone. By N. M. Hancox. vii + 199 pp. figures tables bibliography index. Cambridge University Press New York. 1972. $21

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BOOK REVIEWS
BIOLOGY OF BONE. By N. M. Hancox.
viii + 199 pp., figures, tables, bibliography, index. Cambridge University
Press, New York. 1972. $21.00 (cloth).
It is rather incredible what an accumulation of knowledge the author, who is Professor of Histology and Cell Biology (Medical) of the University of Liverpool, has
been able to achieve in this handy textbook. Still, and maybe unexpectedly, the
result makes most fascinating reading.
The content is split up into four sections. Section 1 is historical and descriptive and deals with general considerations
concerning the function and complexity of
bone tissue; the reciprocity of strong, hard
bone matrix and useful limbs; immobilisation or disuse versus atrophy; osteoporosity; loss of mechanical strength, for example in astronauts. Further the function of
bone as sheltering the deep haemopoietic
tissue of the marrow is stressed, as is the
role of the bone in mineral metabolism and
as a trap €or a variety of blood-borne ions
which may exchange with calcium ions
(i.e., lead, fluorine, radioactive substances),
and finally the difficulty of preparing bone
for investigation as well as the recent interest to orthopedic surgeons centering on
bone biology.
Chapter 2 of Section 1 presents a careful
study of techniques and views for the investigation of bone starting as far back as
Antony van Leeuwenhoek and Clopton
Havers in the 17th and 18th Centuries,
describing the development of the use of
the polarizing microscope at the end of
the 19th Century. The author also accounts
for the chemical and physical treatment
of hard bone tissue to arrive at thin sections and the recent development within
this field, the use of polymer plastics and
low-melting-point metal alloy to hold Samples, new cutting machines, the diamond
“knife” for ultrathin sections, microradiography, “labelled tracers €or autoradiography, and the use of: electron-probe X-ray
microscope for the analysis of the inorganic constituents of bone.
Chapter 3, richly interfoliated with instructive drawings and microphotographs,
is concerned with the varieties of woven
and lamellar bone. It also handles the way
in which bone is deposited, and in detail i t
shows the elaborate image of the construc-
287
tion of both cancellous and compact bone
seen in various enlargements and cutting
directions. Most exciting is the example of
medullary bone taken from a femur of a
laying fowl. Here the cortex consists of
lamellar type; from its inner border, trabeculae of woven bone (“medullary bone”)
extend towards the centre of the shaft.
This kind of bone is thought to be turned
over very rapidly, being resorbed to provide
calcium for the egg shell and being laid
down as a mineral reservoir during the
laying cycle.
Chapter 4 presents a thorough investigation of the basic components of bone matrix, the collagen, the ground substance,
the lipids, the bone salt and its chemistry,
all discussed both from morphological and
chemical standpoints. A comparison is
made with other kind of collagen, and the
author claims that it is at present sure that
bone collagen is similar to other collagens
both in amino acid composition and in its
aggregation to a coiled three chained structure, tropocollagen. It is also more resistant
to dissolution in salt and acid solutions,
probably a function of increased molecular
binding. The ground substance is proved to
contain mucopolysaccharide, and it seems
very likely that the amount of ground substance bears some kind of inverse relationship to the age of bone. The medullary
bone which gives a strong positive PAS
reaction is to be regarded as a sort of bank
from which mineral may be withdrawn
rapidly to provide calcium. Conversely i t
stores calcium when opportunity arises.
The more inert shaft bone reacts weakly
to PAS. The role of the ground substance
of holding and releasing water is claimed
to be most likely. The history of bone salt
identification techniques is given, the size
and arrangement of the bone salt crystals
as seen in the electron microscope, and the
complex chemical components of calcium,
phosphate and hydroxyl ions with small
amounts of cationic strontium, bicarbonate
and fluoride is presented in detail. The exact chemical composition of bone salt is
not known, but its basic formula is presented as Ca10(P04)6(OH)2
and named hydroxyapatite.
Chapter 5 records the first occurrence
of bone and bone-like substances in paleontology, starting with the first vertebrates,
the ostracoderms. It also deals with the dif-
288
BOOK REVIEWS
ferent methods for preparation of fossil
bone, and stresses the result that many of
the amino acids in collagen may persist
in measurable quantities for millions of
years in fossils. Hydroxyproline, however,
seems to be absent.
Section 2, including Chapters 6 to 11, is
entitled “Bone deposition.” Chapter 6 takes
up the histology of osteogenesis, giving a
brief presentation of the two main types
of cells involved, the osteoblasts for the
formation of bone and the osteoclasts for
the erosion of or “resorbtion” of the bone
matrix. The interplay of these two opposite
mechanisms is called bone modelling.
Chapter 7 is devoted to the osteoblast.
The morphological features of this cell
race are described, and its functional significance is discussed. Elegant tissue cultures by Dame Honor Fell (‘32) and subsequent experiments both in vivo and in vitro
have finally proved that osteogenesis only
occurs in the presence of osteoblasts. Electron microscopy has made i t possible to
show that the structural organisation of
the osteoblast is to export protein which in
this case must be collagen, and autoradiography has revealed that “synthesis of collagen takes place by osteoblasts, fibroblasts
and chondrocytes and by odontoblasts.”
Autoradiography has also made it possible
to estimate the production rate of matrix
arrived at by an odontoblast in its most
active phase. Following this is an enumeration of problems still to be solved concerning the generation of bone. This chapter
is one of the most fascinating in the whole
monograph.
In Chapter 8 the complexity of bone calcification is shown. The author first gives a
detailed account of the possible techniques
for the study of calcification and the limitations applicable to most such techniques
except those where electron microscopy is
involved. Next follows the findings of mechanisms of calcification and the present
standpoints of research workers as to the
chemical dynamics and the lack of understanding of this whole series of problems.
The conclusion drawn from research within the field of calcification in biological
systems favours the belief that two different processes are involved in calcification
of cartilage and of bone.
Chapter 9 is an interlude producing a
study of two types of cells being in their
mode of acting more or less “related” to
osteoblasts, i.e., the odontoblasts and the
dentine in the upper end of the animal
kingdom and the calcoblast and the sponge
spicule in the lower end; the former deriving from the mesoderm, the latter found
in the mesohyl of the calcareous sponges.
Chapter 10 goes into particulars about
the osteocytes and the problems involved
with their enigmatic functions. They are
in some respects considered to act as osteoblasts, but by other authors thought to be
involved in the converse process of bone
dissolution. The difficulty of studying their
histology and its changes even with electron microscopy is still a shortcoming.
Chapter 11 discusses some of the most
enigmatic problems in the gradual formation of lamellar from woven bone. There
are mainly two processes involved, first the
appearance and deposition of lamellae close
to preexisting woven bone, and the production of primary osteones, secondly the removal of the woven bone substance by
osteoclasts. But the reason why this order
is followed is still unknown, and Hancox
invokes evolutionary concepts as part of the
explanation of this additional step toward
more perfect construction material, although he admits at the same time that
“such an explanation does not really carry
us much further in our understanding of
the problem.”
Section 3 of this book is headed “Bone
Resorption,” and its first chapter, 12, deals
with osteoclastic bone resorption. We are
first informed that this process, or rather
processes, are associated with the giant
multinucleated osteoclasts, and occur both
normally and in a series of pathological
events. A n example of the normal case is
the bone modelling from foetal life onwards; hyperparathyroidism, tumour cells
and osteomyelitis are examples among others from the pathological field. In all these
cases it is nowadays clear that the osteoclast is the main cellular agent. This chapter is continued by subdivisional accounts
of (a) the general morphology and (b) the
appearance and (c) the association with
bone of the osteoclast. Modern approaches
with autoradiography, electron microscopy, microcinephotography, histochemistry
and biochemistry are reviewed and accompanied by illustrative figures.
The mode of osteoclast action is then dis-
BOOK REVIEWS
289
cussed thoroughly from both its “lysoso- chemists, paleontologists, radiologists and
mal” angle induced by EM results and orthopedists.
from the point of view of chemical attack.
N.-G. GEJVALL
Many unsolved problems are brought out;
University of Stockholm
one of the most striking is how rock-hard
bone edge can be “dissolved by the osteoclast. The origin and fate of the osteoclast
is also dealt with in the light of modern
approaches such as cytoplasmatic labelling
with tritiated trymidine.
Chapter 13 is devoted to “humoral factors in resorption,” and is mainly con- BIOLOGY AND CULTUREIN MODERN PERSPECTIVE. By Joseph G. Jorgensen. 441
cerned with observation on the parathyroid
pp., figures, tables, bibliographies, inhormone which is treated more in detail in
the following pages both from a historicaldex. W. H. Freeman, San Francisco.
1972. $12.00 (cloth), $5.95 (paper).
experimental viewpoint and more specially
as regards hyperparathyroidism in man.
When asked to review a new book, one is
Chapter 14 puts forward ideas of resorption by cells other than osteoclasts, and by nature prone to be critical. In reviewing
here the osteocytes come into the range of a book of readings, in this case a conglomsuspicion. The morphological, cyto- and eration of 41 Scientific American offprints,
biochemical studies in this field are care- one is confronted with a choice of level of
fully reviewed.
criticism - does one evaluate each article
Chapter 15, “unknown factors in bone or the book as a whole? I have chosen the
resorption,” mentions a series of patholog- latter course since almost all of these artiical, reversible, or irreversible changes in cles are written by distinguished scholars
bone resorption, e.g., disuse atrophy, “grey who are experts on the subject matter of
lethal” mutant in mice, cleido-cranial dys- their essays. It would be extremely preostosis in man, and many others; in some sumptuous to assume a knowledge of all
cases they cause aberrations in both bone the topics covered in these articles.
Unfortunately the title of this book imresorption and deposition showing that local factors must exist which exercise influ- plies, intentionally or not, that it will preence on both osteoclasts and osteoblasts, sent us with a synthetic view of man’s
as well as hormonal factors like parathor- biology and culture-the
grand wish of
mone and the recently synthetized calci- American Anthropology. It does not. What
tonin.
we are presented with is an intellectual
Section 4 and its first chapter, 16, are grab bag, rather than a systemically orboth entitled “osteogenic stimuli.” The ganized group of articles. One must keep
most striking and informative example is in mind that the editor was limited to
taken from the healing of bone fractures, what had been published in Scientific
the formation of fibrocartillagenous callus, American at the time of his editorship.
the later appearance of osteoblasts and,
The book is divided into three parts:
the building up of woven bone trabeculae.
Part I: Biological Anthropology - HuThe two last chapters, 17 and 18, are de- man Origins and the History of Life, Huvoted to “bone induction by living implants man Genetics and Evolution, and Evolution
and by nonliving implants.”
of Animal Behavior.
Although the reviewer is a pure morPart 11: Human Prehistory -Tools and
phologist who did not master the biochem- the Development of Culture, The Rise of
ically oriented chapters of this volume, it Civilization in the Old World, and The
has for him been the most sublime delight Rise of Civilization in the New World.
Part 111: Cultural Anthropology - Trato follow the clear and instructive presentation of the deep knowledge of Dr. Hancox. ditional Concerns: Kinship, Polity, EkonThis textbook must be of paramount and omy, Society; A Variation on Traditional
lasting value not only for histologists but Concerns: The Neofunctional Ecology of
for all the categories of researchers men- Hunters; Farmers, and Pastoralists; and
tioned in the author’s preface: physicists, New Concerns: “Haves” and “Have-Nots.”
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