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HUMAN RELATIONS IN OBSTETRICS
973 also taken to rule out the possibility of coincidental painless uterine contraction, in the early stages of the work, by using a tocodynamometer. When a transducer becomes available which will enable the presentation of a 4000-cycle note without loss of intensity it is hoped that resoonses which can only be cochlear may be recorded. Nuffield Audiology Unit, Royal Berkshire Hospital, K. P. MURPHY. Reading. Obstetric Unit, University College Hospital Medical School, C. N. SMYTH. London, W.C.1. Great
care was
AN ATTACK ON CYTOLOGISM
SIR,-Professor Smithers (March 10) has performed a service in pointing out the incompleteness of the common view of cancer which stops short at the properties of the " cancer cell " without considering what may, to borrow a term from other fields of biology, be called tissue ecology. A tissue is a cell population in equilibrium within itself, and normally also in equilibrium with the other units of the total cell population which make up the animal body. This equilibrium is maintained by an interplay of forces which, while they of necessity arise in cells, nevertheless form an environment which considerably modifies the behaviour of individual cells. It has been realised for some time that it is impossible to describe adequately the behaviour of even such a loosely integrated community as the fauna or flora of a wood, or the more closely knit population of a beehive, without taking into account the interactions of the individual elements of these populations. How much more must this be true of mammalian tissues ? The chief characteristics by which we recognise a cancerous population of cells is by their failure to conform to the normal environmental interrelations-that is to say that such a popu-, lation " invades " the surrounding tissues with which it is no " " longer in equilibrium, or metastasises to and grows in distant parts in which the environment is normally unsuitable for its continued existence. Nevertheless within itself the cancerous tissue is integrated, often to a marked extent. To neglect this aspect leads to the fallacy found in Dr. Hewitt’s letter (April 14) that " any variant cell arising in a large tumour-cell population will eventually ’take-over ’ if it has an intrinsically higher rate of division." Not only is the rate of division seldom strictly intrinsic but partially dependent on factors arising outside the cell, but also a potentially increased rate of division will not avail the cell if the variation at the same time puts it at a disadvantage by disturbing its equilibrium with the surrounding tissue. At the moment our knowledge of tissue integration is mainly confined to effects on cell division-e.g., by hormonesrather than to the spatial aspects. In this latter field we are certainly hampered by our lack of knowledge of the normal biological factors at work. Contrary to the depressing view of Dr. Hewitt concerning the introduction of " teleological enigmas" this appears to me a reason for encouraging the investigation of the normal in conjunction with our probing of the abnormal. It is certainly a difficult field but maybe shying from the difficulties in the past accounts for many of our present confusions. We can approach tissue behaviour through the " tissue aspects " of the constituent cells, a line which a few of us are now beginning to look into. Even such an apparently simple matter as cell adhesion can be considered as an important element in tissue arrangement, not only through mechanical effects but also in all probability through more subtle effects on cell interactions. Encouraged by Dr. Hewitt’s final paragraph may I suggest that cancer cells are ones which make up the malignant component of a cancerous
tissue ? Department of Experimental Pathology and Cancer Research, School of Medicine, Leeds.
J. O. LAWS.
HUMAN RELATIONS IN OBSTETRICS SIR,-Your annotation (April 14) calls for some comment, which I base on experience in a university obstetric unit in Sweden, though practice is similar in other parts of the country. During the last weeks of pregnancy, mothers go on a gymnastics-relaxation-information course, run by midwives and/or physiotherapists. There are groups of 15 to 20 mothers who attend six to eight times once a week for 2 hours. Once during each course, an anaesthetist and an obstetrician attend, supervising the relaxation, giving advice about labour, and staying afterwards to answer questions on pain relief and conduct of labour. The mothers are encouraged and expect to bring with them to the labour ward their husbands, who stay with them throughout labour, except in complicated cases. The husbands help the wives to relax, encourage them when they are tired, keep them company during the hours of waiting, and are present at the actual birth to share the experience. When the third stage is over, the parents and the newborn are left together for a couple of hours in peace and quiet.
practice goes a long way towards meeting staff shortages. During labour, the midwife comes into the labour room at frequent intervals to check the foetal position and foetal-heart rate, and helps the mother to relax. If there is the slightest difficulty, the husband has only to press a button and the midwife comes in immediately. In those Swedish hospitals where the husbands have been present during labour, all concerned have been well satisfied. Almost all the mothers ask if they may have their husbands with them when they have their babies. In some hospitals courses have been organised for fathers, preparing them to help their wives during labour. This
University Hospital, Uppsala, Sweden.
BASIL FINER.
CALCIUM BALANCE MADE EASY
SIR,-Dr. Jackson’s delightful paper (April 21) with its very arresting diagrams will no doubt be carefully studied by examination candidates and others who have only a passing interest in the -subject. It is therefore particularly important that the text should bear careful scrutiny and be free from ambiguity. For this reason I take the liberty of drawing attention to one feature which is liable to cause serious misunderstanding about a small but vital point-namely, the use of the term " decalcification ". Dr. Jackson states that negative calcium balance, due to malabsorption of calcium, produces decalcification of bone, and that if the cause is vitamin-D deficiency, the resulting bone lesion is osteomalacia. Later on, however, he refers to the negative calcium balance produced by hypercalcuria and indicates that in this case the resulting " decalcification " may produce osteoporosis. I am sure that Dr. Jackson would be the first to agree that these statements could be misinterpreted. The low mineral content of osteomalacic bone is not due to decalcification, but to failure of mineralisation of new bone as it is laid down. This failure is usually associated with (and probably results from) a reduction in the concentration of calcium and phosphorus in the extracellular fluid. The cause of the latter lies outside the scope of this letter, but it is unlikely that it arises from malabsorption of calcium or the negative calcium balance which this produces. Hypercalcuria can also cause negative calcium balance, as Dr. Jackson indicates, but there is no reason to suppose that this produces " decalcification " of bone. Like any other form of negative calcium balance, it appears to cause a virtually simultaneous destruction of the mineral and organic constituents of bone, leading to a reduction in bone mass,
care was
AN ATTACK ON CYTOLOGISM
SIR,-Professor Smithers (March 10) has performed a service in pointing out the incompleteness of the common view of cancer which stops short at the properties of the " cancer cell " without considering what may, to borrow a term from other fields of biology, be called tissue ecology. A tissue is a cell population in equilibrium within itself, and normally also in equilibrium with the other units of the total cell population which make up the animal body. This equilibrium is maintained by an interplay of forces which, while they of necessity arise in cells, nevertheless form an environment which considerably modifies the behaviour of individual cells. It has been realised for some time that it is impossible to describe adequately the behaviour of even such a loosely integrated community as the fauna or flora of a wood, or the more closely knit population of a beehive, without taking into account the interactions of the individual elements of these populations. How much more must this be true of mammalian tissues ? The chief characteristics by which we recognise a cancerous population of cells is by their failure to conform to the normal environmental interrelations-that is to say that such a popu-, lation " invades " the surrounding tissues with which it is no " " longer in equilibrium, or metastasises to and grows in distant parts in which the environment is normally unsuitable for its continued existence. Nevertheless within itself the cancerous tissue is integrated, often to a marked extent. To neglect this aspect leads to the fallacy found in Dr. Hewitt’s letter (April 14) that " any variant cell arising in a large tumour-cell population will eventually ’take-over ’ if it has an intrinsically higher rate of division." Not only is the rate of division seldom strictly intrinsic but partially dependent on factors arising outside the cell, but also a potentially increased rate of division will not avail the cell if the variation at the same time puts it at a disadvantage by disturbing its equilibrium with the surrounding tissue. At the moment our knowledge of tissue integration is mainly confined to effects on cell division-e.g., by hormonesrather than to the spatial aspects. In this latter field we are certainly hampered by our lack of knowledge of the normal biological factors at work. Contrary to the depressing view of Dr. Hewitt concerning the introduction of " teleological enigmas" this appears to me a reason for encouraging the investigation of the normal in conjunction with our probing of the abnormal. It is certainly a difficult field but maybe shying from the difficulties in the past accounts for many of our present confusions. We can approach tissue behaviour through the " tissue aspects " of the constituent cells, a line which a few of us are now beginning to look into. Even such an apparently simple matter as cell adhesion can be considered as an important element in tissue arrangement, not only through mechanical effects but also in all probability through more subtle effects on cell interactions. Encouraged by Dr. Hewitt’s final paragraph may I suggest that cancer cells are ones which make up the malignant component of a cancerous
tissue ? Department of Experimental Pathology and Cancer Research, School of Medicine, Leeds.
J. O. LAWS.
HUMAN RELATIONS IN OBSTETRICS SIR,-Your annotation (April 14) calls for some comment, which I base on experience in a university obstetric unit in Sweden, though practice is similar in other parts of the country. During the last weeks of pregnancy, mothers go on a gymnastics-relaxation-information course, run by midwives and/or physiotherapists. There are groups of 15 to 20 mothers who attend six to eight times once a week for 2 hours. Once during each course, an anaesthetist and an obstetrician attend, supervising the relaxation, giving advice about labour, and staying afterwards to answer questions on pain relief and conduct of labour. The mothers are encouraged and expect to bring with them to the labour ward their husbands, who stay with them throughout labour, except in complicated cases. The husbands help the wives to relax, encourage them when they are tired, keep them company during the hours of waiting, and are present at the actual birth to share the experience. When the third stage is over, the parents and the newborn are left together for a couple of hours in peace and quiet.
practice goes a long way towards meeting staff shortages. During labour, the midwife comes into the labour room at frequent intervals to check the foetal position and foetal-heart rate, and helps the mother to relax. If there is the slightest difficulty, the husband has only to press a button and the midwife comes in immediately. In those Swedish hospitals where the husbands have been present during labour, all concerned have been well satisfied. Almost all the mothers ask if they may have their husbands with them when they have their babies. In some hospitals courses have been organised for fathers, preparing them to help their wives during labour. This
University Hospital, Uppsala, Sweden.
BASIL FINER.
CALCIUM BALANCE MADE EASY
SIR,-Dr. Jackson’s delightful paper (April 21) with its very arresting diagrams will no doubt be carefully studied by examination candidates and others who have only a passing interest in the -subject. It is therefore particularly important that the text should bear careful scrutiny and be free from ambiguity. For this reason I take the liberty of drawing attention to one feature which is liable to cause serious misunderstanding about a small but vital point-namely, the use of the term " decalcification ". Dr. Jackson states that negative calcium balance, due to malabsorption of calcium, produces decalcification of bone, and that if the cause is vitamin-D deficiency, the resulting bone lesion is osteomalacia. Later on, however, he refers to the negative calcium balance produced by hypercalcuria and indicates that in this case the resulting " decalcification " may produce osteoporosis. I am sure that Dr. Jackson would be the first to agree that these statements could be misinterpreted. The low mineral content of osteomalacic bone is not due to decalcification, but to failure of mineralisation of new bone as it is laid down. This failure is usually associated with (and probably results from) a reduction in the concentration of calcium and phosphorus in the extracellular fluid. The cause of the latter lies outside the scope of this letter, but it is unlikely that it arises from malabsorption of calcium or the negative calcium balance which this produces. Hypercalcuria can also cause negative calcium balance, as Dr. Jackson indicates, but there is no reason to suppose that this produces " decalcification " of bone. Like any other form of negative calcium balance, it appears to cause a virtually simultaneous destruction of the mineral and organic constituents of bone, leading to a reduction in bone mass,