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TUBERCULIN-JELLY TEST
54 4. In one case lactation commenced as A.D.H. fell to its lowest level, and during the following day A.D.H. concentration In this case lactation has been inadequate rose rapidly. to satisfy the child. _
In each of three patients confined in the Brisbane General Hospital and placed on a strict fluid inputoutput regime, lactation commenced as the urinary output reached its maximum. The study is being continued. Department of Physiology, University of Queensland, Brisbane, Australia.
ROSS WILSON HAWKER.
TUBERCULIN-JELLY TEST
SiR.,-The unreliability of the tuborculin-jelly test, as reported by Dr. Grzybowski (Dec. 15), was confirmed by the experience of this department when, for more than a year, we applied it to all children admitted to the wards together with the serial Mantoux test. Nearly 10% of children showing a positive Mantoux test were negative to the jelly, and there were a number of false positives. The Volmer patch-test appears to be even less reliable.
The uncertainty depends on ignorance-not the ignorance of the user but the ignorance of the scientist. As we follow the processes of gamete development, union, and the preliminary stages in the fixation and development of the zygote, we see that at every turn we are ignorant of the mechanisms involved. We know something of them and, when we consider how few scientists have taken up this work, our knowledge is in many directions impressive ; but we know too little even to begin to plan a rational contraceptive technique. Until we know more, all methods must depend on the purest empiricism. The necessary information can be gained in two ways. A research unit could be set up to investigate the metabolism of gametes and zygote with special regard to methods of interfering with it. If the problem were urgent this would clearly be the course to adopt. But ad-hoc research raises special difficulties. People with spontaneous enthusiasm for a subject are likely to
contribute more than those who come in because some pressure has been put on them. The alternative is to see whether those already working on metabolic problems This is unfortunate, since we are all anxious to avoid can be interested in the gametes. of a giving children pricks ; but until the reliability Our knowledge of the enzyme processes in yeast and surface test has been demonstrated the practising physician must continue to use the intradermal method. liver is now extensive. Most of this knowledge was Children’s Department, gained by people not specifically interested in yeast or DUNCAN LEYS. Farnborough Hospital, liver but interested in enzymic processes and using tissues Kent. such as these as convenient material. Had other tissues been as readily available they would have been used and BASIC RESEARCH INTO CONTRACEPTION somewhat different mechanisms would have been disSIR,—Repeatedly during the last century the fear covered. If by now as much work had been done on the has been expressed that the population of the world may as on many other tissues, the design of an outstrip the food-supply, but advances in technology and gametes efficient contraceptive would probably be a matter of the opening up of new lands have so far proved the fears developmental rather than fundamental research. groundless. There is a danger that these false alarms The biochemistry of the gametes is intrinsically an will produce complacency as in the fable of the child interesting subject. We have here systems of great that cried " Wolf ! Wolf !" but ultimately got eaten. but with restricted immediate activity. potentiality Fecundity is potentially unlimited, but agricultural There is, for example, no reason to think that sperm can productivity is not. Some time, therefore, we will find bring about as wide a range of actions as yeast or liver; the wolf at the door, and we should consider now, in good some of the actions that they do perform are probably time, what we propose to do about it. If the system is simpler we should be able more unique. The ready answer is that people could achieve whatto comprehend completely what is going on in quickly ever level of population they wished if they were it so that a balance-sheet for its total activity could be informed about contraceptive technique and had the drawn up ; and this is the aim of biochemistry. This view was taken by the necessary equipment. Hitherto it has not been easy to get mammalian sperm Royal Commission on Population,’ which observed in quantity, but now bull sperm can be had from (paragraph 427) : artificial-insemination centres and human sperm could Control by men and women over the numbers of their be had from subfertility clinics. Furthermore, the children is one of the first conditions of their own and the of micro-methods is diminishing the amount community’s welfare and in our view mechanical and chemical development material needed. of There is therefore no reason why methods of contraception have to be accepted as part of the sperm should not now be used as one of the normal agents modern means, however imperfect, by which it can be in fundamental metabolic work in many centres, but exercised." fact is not yet widely recognised. The strategy of this The Commission seemed to be disposed to accept, not applied research done, when it is obvious that it only contraception, but also its imperfections ; and getting cannot usefully start till we have more fundamental evidence was presented that these are formidable. knowledge, is to see that people who are already engaged Unless methods very much better than those now in fundamental research sometimes use the material in available are discovered a mere increase in contraceptive which we have a practical interest. Certain experimental knowledge is not likely to be effective. Commenting on a materials become traditional for no very obvious have widely used and advertised contraceptive, which claims reasons, and it is undoubtedly easier to go on working a failure-rate of " only a corre1.53%," peripatetic them because so much is already known about the spondent in THE LANCET2 observed pungently : " from with under which experiments should be made. conditions the Kinsey report a failure-rate ofonly 1-53% ’ would all organisms and all tissues will be But ultimately mean pregnancy every eleven months." This is an and we would be wise to start with those in studied, but there is a of it. truth in If we germ exaggeration, which we have a practical interest. Until we know as. are going to urge people, especially primitive people, to much about the biochemistry of human gametes as we make even slight changes in their domestic habits we do about rabbit liver there is little chance of discovering should have better methods than this. Present methods those biochemical anomalies on which differential are neither foolproof nor certain, and this element of uncertainty can be used with great effect by any group inhibition-i.e., rationally based contraception-must depend. of people bent, for any reason, on opposing a policy of Some time it will be necessary to study the problem population restriction. directly and to make use of all the information available 1. Report of the Royal Commission on Population. H.M. Stationery both about gametes and the hormonal control of their Office, 1949. 2. Lancet, 1951, ii, 176. development, and for this a fully equipped institute will "
In each of three patients confined in the Brisbane General Hospital and placed on a strict fluid inputoutput regime, lactation commenced as the urinary output reached its maximum. The study is being continued. Department of Physiology, University of Queensland, Brisbane, Australia.
ROSS WILSON HAWKER.
TUBERCULIN-JELLY TEST
SiR.,-The unreliability of the tuborculin-jelly test, as reported by Dr. Grzybowski (Dec. 15), was confirmed by the experience of this department when, for more than a year, we applied it to all children admitted to the wards together with the serial Mantoux test. Nearly 10% of children showing a positive Mantoux test were negative to the jelly, and there were a number of false positives. The Volmer patch-test appears to be even less reliable.
The uncertainty depends on ignorance-not the ignorance of the user but the ignorance of the scientist. As we follow the processes of gamete development, union, and the preliminary stages in the fixation and development of the zygote, we see that at every turn we are ignorant of the mechanisms involved. We know something of them and, when we consider how few scientists have taken up this work, our knowledge is in many directions impressive ; but we know too little even to begin to plan a rational contraceptive technique. Until we know more, all methods must depend on the purest empiricism. The necessary information can be gained in two ways. A research unit could be set up to investigate the metabolism of gametes and zygote with special regard to methods of interfering with it. If the problem were urgent this would clearly be the course to adopt. But ad-hoc research raises special difficulties. People with spontaneous enthusiasm for a subject are likely to
contribute more than those who come in because some pressure has been put on them. The alternative is to see whether those already working on metabolic problems This is unfortunate, since we are all anxious to avoid can be interested in the gametes. of a giving children pricks ; but until the reliability Our knowledge of the enzyme processes in yeast and surface test has been demonstrated the practising physician must continue to use the intradermal method. liver is now extensive. Most of this knowledge was Children’s Department, gained by people not specifically interested in yeast or DUNCAN LEYS. Farnborough Hospital, liver but interested in enzymic processes and using tissues Kent. such as these as convenient material. Had other tissues been as readily available they would have been used and BASIC RESEARCH INTO CONTRACEPTION somewhat different mechanisms would have been disSIR,—Repeatedly during the last century the fear covered. If by now as much work had been done on the has been expressed that the population of the world may as on many other tissues, the design of an outstrip the food-supply, but advances in technology and gametes efficient contraceptive would probably be a matter of the opening up of new lands have so far proved the fears developmental rather than fundamental research. groundless. There is a danger that these false alarms The biochemistry of the gametes is intrinsically an will produce complacency as in the fable of the child interesting subject. We have here systems of great that cried " Wolf ! Wolf !" but ultimately got eaten. but with restricted immediate activity. potentiality Fecundity is potentially unlimited, but agricultural There is, for example, no reason to think that sperm can productivity is not. Some time, therefore, we will find bring about as wide a range of actions as yeast or liver; the wolf at the door, and we should consider now, in good some of the actions that they do perform are probably time, what we propose to do about it. If the system is simpler we should be able more unique. The ready answer is that people could achieve whatto comprehend completely what is going on in quickly ever level of population they wished if they were it so that a balance-sheet for its total activity could be informed about contraceptive technique and had the drawn up ; and this is the aim of biochemistry. This view was taken by the necessary equipment. Hitherto it has not been easy to get mammalian sperm Royal Commission on Population,’ which observed in quantity, but now bull sperm can be had from (paragraph 427) : artificial-insemination centres and human sperm could Control by men and women over the numbers of their be had from subfertility clinics. Furthermore, the children is one of the first conditions of their own and the of micro-methods is diminishing the amount community’s welfare and in our view mechanical and chemical development material needed. of There is therefore no reason why methods of contraception have to be accepted as part of the sperm should not now be used as one of the normal agents modern means, however imperfect, by which it can be in fundamental metabolic work in many centres, but exercised." fact is not yet widely recognised. The strategy of this The Commission seemed to be disposed to accept, not applied research done, when it is obvious that it only contraception, but also its imperfections ; and getting cannot usefully start till we have more fundamental evidence was presented that these are formidable. knowledge, is to see that people who are already engaged Unless methods very much better than those now in fundamental research sometimes use the material in available are discovered a mere increase in contraceptive which we have a practical interest. Certain experimental knowledge is not likely to be effective. Commenting on a materials become traditional for no very obvious have widely used and advertised contraceptive, which claims reasons, and it is undoubtedly easier to go on working a failure-rate of " only a corre1.53%," peripatetic them because so much is already known about the spondent in THE LANCET2 observed pungently : " from with under which experiments should be made. conditions the Kinsey report a failure-rate ofonly 1-53% ’ would all organisms and all tissues will be But ultimately mean pregnancy every eleven months." This is an and we would be wise to start with those in studied, but there is a of it. truth in If we germ exaggeration, which we have a practical interest. Until we know as. are going to urge people, especially primitive people, to much about the biochemistry of human gametes as we make even slight changes in their domestic habits we do about rabbit liver there is little chance of discovering should have better methods than this. Present methods those biochemical anomalies on which differential are neither foolproof nor certain, and this element of uncertainty can be used with great effect by any group inhibition-i.e., rationally based contraception-must depend. of people bent, for any reason, on opposing a policy of Some time it will be necessary to study the problem population restriction. directly and to make use of all the information available 1. Report of the Royal Commission on Population. H.M. Stationery both about gametes and the hormonal control of their Office, 1949. 2. Lancet, 1951, ii, 176. development, and for this a fully equipped institute will "