1236 will fall into the commercial category. However, 2 303 000 commercial experiments in 1976 that
example, there
were
diagnostic, cancer research, or mandatory drug testing. Exactly what this enormous figure consists of we do not were not
yet know, but it will include the miserable deaths of hundreds of animals in the testing of new cosmetics, toiletries, non-nutritive food additives, and other inessential consumer products. Professor Shuster is also mistaken if he believes that the reformer’s creed "rests on no absolute moral standards". The idea that all sentients have rights is rapidly gaining ground in philosophical and theological circles and should make sense to scientists.. If we accept the darwinian idea of biological kinship then what is the logical reason why there should not be moral kinship? On what grounds, other than sentimentality, do we discriminate so unfairly against other species? Warneford
Hospital, Headington, Oxford OX3 7JX
RICHARD D. RYDER
relieved or cured with bone-marrow, syngeneic or H-2 compatible. Further experiences indicate that the degree of clearance of juvenile scaffolding bone is related to the cell dose given. Even clones of syngeneic cells may not expand sufficiently to produce ultimate cure and H-2 compatible but allogeneic cells are usually rejected in time. The radiographs of the case of Ballet et al., not ideally reproduced on Lancet paper, are reminiscent of pictures we see in mice4where, after initial resolution, relapse is occurring. The data given (594 mg/day calcium accretion, 594 mg/day positive calcium balance) also suggest that bone resorption must be low at this time. We, therefore, question the statement about the cells transplanted: "their persistence can be anticipated according to the observation made in the Op/Op rat", and it remains to be seen whether the rat or the mouse is the better model for man. Work on both should proceed. Charles Salt Research Centre, Robert Jones and Agnes Hunt
Orthopædic Hospital, Oswestry, Shropshire SY10 7AG M.R.C. Radiobiology Unit,
REFERRING URGENT PSYCHIATRIC PROBLEMS your caption Mental Health for the report by Dr Bowman and Dr Sturgeon upon urgent psychiatric cases (Nov. 19, p. 1067). Whose health? The report reveals much more than it states. Bowman and Sturgeon examine cases perceived as urgent by the referring agencies in one setting and assessed by themselves in another, and note disagreements. They conclude that referring agents "find assessment difficult" and that students in their clinic "will learn to cope better". The narrow sympathy astounds, excused I hope by as narrow experience. Long ago house-physicians understood that asthma often got better in the ambulance. House-surgeons know that some acute abdominal pain settles under observation. Referral is sometimes therapeutic. To be exposed as a specialist in one discipline to the problems of another is the experience of psychiatrists too; I wonder how Bowman and
SIR,-I
was
dismayed by
Sturgeon perform then. To be exposed without relief in the community to the extraordinary pressures of agitated, demanding, sometimes manipulative, disturbed people surrounded by neighbours, relatives, and even social services is hard indeed. There are psychiatrists willing to provide asylum as well as diagnose cases-an exclusive range of diagnoses too-without leaping to the conclusion that ignorance and inability to cope amount to
two-thirds of my troubles.
Medical Centre,
Shipston-on-Stour, Warwickshire CV36
GUY HARRIS
4BQ
BONE-MARROW TRANSPLANTATION IN OSTEOPETROSIS
SIR,-We welcome the report by Dr Ballet and his colleagues (Nov. 26, p. 1137) of the results of treatment of congenital osteopetrosis with bone-marrow of a sibling. The rationale was
based
op/op atrophy’
these workers’ experience with the osteopetrotic This genotype is said to be associated with thymic as well as osteopetrosis, and this may facilitate accepon
rat.
of a graft. Our preliminary experiencez.3 with osteopetrotic mt1mi mice (in which osteopetrosis is associated with microphthalmia and other phenotypic features) was that the osteopetrosis was tance
2.
Milhaud, G., Labat, M.-L., Parant, M., Damais, C., Chedid, L. Proc. natn. Acad. Sci. U.S.A. 1977, 74, 339. Barnes, D. W. H., Loutit, J. F., Sansom, J. M. Proc. R. Soc. B. 1975, 188,
3.
Loutit, J. F., Sansom, J. M. Calcif. Tiss. Res. 1976, 20, 251.
1.
501.
Harwell, Didcot, Oxon OX 11 0RD
N. W. NISBET J. MENAGE
J. F. LOUTIT
HÆMORRHAGE AND LOW-DOSE HEPARIN
SIR,-Icannot understand the concern expressed by Mr Britton and his colleagues (Sept. 17, p. 604) about the safety of low-dose heparin prophylaxis in the prevention of postoperative fatal pulmonary embolism. 3 (0.3%) out of their 1000 patients receiving heparin had life-threatening postoperative bleeding. This has nothing to do with the administration of heparin because it represents the expected frequency of this complication after elective and emergency major abdominal surgery. In the multicentre trial’ 5 out of 2076 controls died from postoperative haemorrhage. Dr Sharnoffs comments (Nov. 19, p. 1087) are equally disappointing. He maintains that 5000 units of heparin administered 2 h before surgery is likely to produce "hypocoagulation" and serious haemorrhage because heparin is given too close to the time of surgery; when 10 000 units of heparin has been administered 8-10 h preoperatively no serious haemorrhage has occurred during surgery. However, no significant difference in plasma-heparin concentraton has been observed when the samples were withdrawn 8 h after administration of 10 000 units of heparin compared with the samples obtained 2 h after injection of 5000 units.2 Furthermore, no evidence has ever been presented in randomised prospective studies that monitoring the dose of heparin to be administered during the postoperative period will reduce the frequency of bleeding complications. Yet Sharnoff considers this to be the most crucial part of low-dose heparin prophylaxis. The evidence that low-dose heparin prophylaxis prevents death from pulmonary embolism is convincing. In the international multicentre trial,’ 2 out of 2045 heparin-treated patients died from massive pulmonary embolism compared with 16 out of 2076 controls. These findings are further supported by the data presented by Britton et at, since only 1 out of 1000 patients receiving heparin prophylaxis died from massive pulmonary embolism. The most persuasive evidence for the efficacy of low-dose heparin is presented in the review by Matt and Gruber;3 42 (0-8%) out of 3943 control patients had fatal postoperative pulmonarv tnbolism compared with 8 (0.2%) out of 3919 heparin-treated patients (P
example, there
were
diagnostic, cancer research, or mandatory drug testing. Exactly what this enormous figure consists of we do not were not
yet know, but it will include the miserable deaths of hundreds of animals in the testing of new cosmetics, toiletries, non-nutritive food additives, and other inessential consumer products. Professor Shuster is also mistaken if he believes that the reformer’s creed "rests on no absolute moral standards". The idea that all sentients have rights is rapidly gaining ground in philosophical and theological circles and should make sense to scientists.. If we accept the darwinian idea of biological kinship then what is the logical reason why there should not be moral kinship? On what grounds, other than sentimentality, do we discriminate so unfairly against other species? Warneford
Hospital, Headington, Oxford OX3 7JX
RICHARD D. RYDER
relieved or cured with bone-marrow, syngeneic or H-2 compatible. Further experiences indicate that the degree of clearance of juvenile scaffolding bone is related to the cell dose given. Even clones of syngeneic cells may not expand sufficiently to produce ultimate cure and H-2 compatible but allogeneic cells are usually rejected in time. The radiographs of the case of Ballet et al., not ideally reproduced on Lancet paper, are reminiscent of pictures we see in mice4where, after initial resolution, relapse is occurring. The data given (594 mg/day calcium accretion, 594 mg/day positive calcium balance) also suggest that bone resorption must be low at this time. We, therefore, question the statement about the cells transplanted: "their persistence can be anticipated according to the observation made in the Op/Op rat", and it remains to be seen whether the rat or the mouse is the better model for man. Work on both should proceed. Charles Salt Research Centre, Robert Jones and Agnes Hunt
Orthopædic Hospital, Oswestry, Shropshire SY10 7AG M.R.C. Radiobiology Unit,
REFERRING URGENT PSYCHIATRIC PROBLEMS your caption Mental Health for the report by Dr Bowman and Dr Sturgeon upon urgent psychiatric cases (Nov. 19, p. 1067). Whose health? The report reveals much more than it states. Bowman and Sturgeon examine cases perceived as urgent by the referring agencies in one setting and assessed by themselves in another, and note disagreements. They conclude that referring agents "find assessment difficult" and that students in their clinic "will learn to cope better". The narrow sympathy astounds, excused I hope by as narrow experience. Long ago house-physicians understood that asthma often got better in the ambulance. House-surgeons know that some acute abdominal pain settles under observation. Referral is sometimes therapeutic. To be exposed as a specialist in one discipline to the problems of another is the experience of psychiatrists too; I wonder how Bowman and
SIR,-I
was
dismayed by
Sturgeon perform then. To be exposed without relief in the community to the extraordinary pressures of agitated, demanding, sometimes manipulative, disturbed people surrounded by neighbours, relatives, and even social services is hard indeed. There are psychiatrists willing to provide asylum as well as diagnose cases-an exclusive range of diagnoses too-without leaping to the conclusion that ignorance and inability to cope amount to
two-thirds of my troubles.
Medical Centre,
Shipston-on-Stour, Warwickshire CV36
GUY HARRIS
4BQ
BONE-MARROW TRANSPLANTATION IN OSTEOPETROSIS
SIR,-We welcome the report by Dr Ballet and his colleagues (Nov. 26, p. 1137) of the results of treatment of congenital osteopetrosis with bone-marrow of a sibling. The rationale was
based
op/op atrophy’
these workers’ experience with the osteopetrotic This genotype is said to be associated with thymic as well as osteopetrosis, and this may facilitate accepon
rat.
of a graft. Our preliminary experiencez.3 with osteopetrotic mt1mi mice (in which osteopetrosis is associated with microphthalmia and other phenotypic features) was that the osteopetrosis was tance
2.
Milhaud, G., Labat, M.-L., Parant, M., Damais, C., Chedid, L. Proc. natn. Acad. Sci. U.S.A. 1977, 74, 339. Barnes, D. W. H., Loutit, J. F., Sansom, J. M. Proc. R. Soc. B. 1975, 188,
3.
Loutit, J. F., Sansom, J. M. Calcif. Tiss. Res. 1976, 20, 251.
1.
501.
Harwell, Didcot, Oxon OX 11 0RD
N. W. NISBET J. MENAGE
J. F. LOUTIT
HÆMORRHAGE AND LOW-DOSE HEPARIN
SIR,-Icannot understand the concern expressed by Mr Britton and his colleagues (Sept. 17, p. 604) about the safety of low-dose heparin prophylaxis in the prevention of postoperative fatal pulmonary embolism. 3 (0.3%) out of their 1000 patients receiving heparin had life-threatening postoperative bleeding. This has nothing to do with the administration of heparin because it represents the expected frequency of this complication after elective and emergency major abdominal surgery. In the multicentre trial’ 5 out of 2076 controls died from postoperative haemorrhage. Dr Sharnoffs comments (Nov. 19, p. 1087) are equally disappointing. He maintains that 5000 units of heparin administered 2 h before surgery is likely to produce "hypocoagulation" and serious haemorrhage because heparin is given too close to the time of surgery; when 10 000 units of heparin has been administered 8-10 h preoperatively no serious haemorrhage has occurred during surgery. However, no significant difference in plasma-heparin concentraton has been observed when the samples were withdrawn 8 h after administration of 10 000 units of heparin compared with the samples obtained 2 h after injection of 5000 units.2 Furthermore, no evidence has ever been presented in randomised prospective studies that monitoring the dose of heparin to be administered during the postoperative period will reduce the frequency of bleeding complications. Yet Sharnoff considers this to be the most crucial part of low-dose heparin prophylaxis. The evidence that low-dose heparin prophylaxis prevents death from pulmonary embolism is convincing. In the international multicentre trial,’ 2 out of 2045 heparin-treated patients died from massive pulmonary embolism compared with 16 out of 2076 controls. These findings are further supported by the data presented by Britton et at, since only 1 out of 1000 patients receiving heparin prophylaxis died from massive pulmonary embolism. The most persuasive evidence for the efficacy of low-dose heparin is presented in the review by Matt and Gruber;3 42 (0-8%) out of 3943 control patients had fatal postoperative pulmonarv tnbolism compared with 8 (0.2%) out of 3919 heparin-treated patients (P
