276
hormone,
such as 3, 3’, 5’ T3 (reverse T3) is present in increased concentration and may prevent the expected
reduced thyroid-hormone levels.17 preliminary observations indicate that care is required in the interpretation of thyroid-hormone levels in seriously ill patients, since subnormal T4 as well as T3 T.S.H. response to
These
levels may
occur.
The question also arises whether
therapeutic intervention with exogenous T3 (or oral T.R.H.) might be justified since reversion of some of the metabolic changes which follow
M.I. may
improve prognosis.
Department of Materia Medica and Radioimmunoassay Unit, Stobhill General Hospital, Glasgow G21 3UW.
D. G. MCLARTY W. A. RATCLIFFE K. McCOLL D. STONE J. G. RATCLIFFE.
Committee Z-79 has found the U.S. Military Standard: Human Engineering Design Criteria for Military Systems, Equipment and Facilities, MIL-STD-1472B, Dec. 31, 1974, of very great use in the location, labelling, and safe design of controls and instruments. This valuable source was drawn to our attention by Mr Robert Cangelosi (Food and Drug Administration, Bureau of Medical Devices, 5600 Fishers Lane, Rockville, Maryland 20852), who, I am sure, would be happy to make copies available to engineers and others working to improve the safety of anaesthesia and other medical equipment. Mount Sinai School of Medicine, City University of New York, Fifth Avenue and 100th Street, New York, New York 10029,
L. RENDELL-BAKER.
U.S.A.
CURIOUS CURD SiR,—Concerning the letter from Dr Bennett and Dr Herman (June 28, p. 1430), the important point is that warm undiluted Jersey milk was given in appreciable quantity to an infant. Jersey milk is much richer than Friesian, which is now the commonest milk in the United Kingdom, as shown by the following compositional data (typical values per cent):
FOLATE-RESPONSIVE SCHIZOPHRENIA SIR,-Irefer to your interesting leader (June 7, p. 1283)
folate-responsive schizophrenia in which you suggest some patients may be deficient in methylenetetrahydrofolate. In the course of a retrospective survey1 of psychiatric inpatients with a low serum-folate at admission, a group given folate supplements virtually randomly were compared for a time in hospital with patients not so treated. The groups were comparable on age and sex, all had normal serum-Bl2 levels and were otherwise given conventional psychiatric treatment. The results were: on
that
Folate No.
The Jersey milk would form a large curd in the infant’s stomach, which would then by vomiting be forced up the oesophagus and so acquire the sausage shape depicted. It then became lodged at the back of the throat and so obstructed the trachea. This phenomenon is not confined to infants. Some years ago a chemical engineer drank a glassful of an experimentally concentrated milk (6/1) and this formed a tough curd in the stomach which took six months to disperse. Undiluted Jersey milk should never be taken in quantity by infants and adults with weak digestion. Milk which has been precurdled, as in yoghourt, and milk which has been predigested by pancreatin are quite safe in this respect since they do not form a coherent curd in the stomach. Reading, Berks.
J. G. DAVIS.
(days)
3 10 7
44 3 23-3 76-3
Schizophrenia Endogenous depression Organic psychoses ..
701 32-9 99-6
The folate-treated patients spent significantly less time hospital than those not given folate (Mann-Whitney u test, u=203; z=1-922; p=0-027 [one-tailed]), a difference not seen in the low-folate patients with other psychiatric diagnoses. Though factors other than clinical improvement may determine length of time in hospital, it is a stable criterion free from observer bias. As there is now good evidence of associations between folate deficiency and mental illness,2,3 there is a pressing need for further investigation of its possible aetiological role and a prospective double-blind trial of folic acid in low serum-folate patients with schizophrenia and other psychiatric conditions. Northwick Park Hospital,
SIR,-Anaestherists in recent years have otten spent some time in foreign countries obtaining training and experience. Dr Wilson (July 5, p. 35) emphasised the ever-present hazard posed by the dissimilar layouts of controls on anaesthetic apparatus between various countries and manufacturers. An example of one difficulty is the location and marking of the O2 flowmeter on anaesthetic gas machines. Many O2 controls in Europe are on the left and may be coloured white or blue (in Germany) whereas in the U.S. most machines have the O2 control on the right, and coloured green!I Dr Wilson did well to draw our attention to the extensive work that has been carried out in the aircraft industry and by the Armed Forces to reduce the hazard from misread instruments and controls. British Standards Institute Committee SGC 15 and A.N.S.I. Committee Z-79 are working on an I.S.O. draft standard intended to increase the safety and define the performance expected of anaesthetic gas machines.
Middlesex HA1 3UJ.
Chopra, I. J. J. clin. Invest. 1974, 54, 583.
10 8 12
in
DESIGN OF ANÆSTHESIA APPARATUS
17.
Non-folate Time of (days) patients No.
Time
of patients
Harrow,
M. W. P. CARNEY.
SCHIZOPHRENIA
SIR,-I found your leading article (Aug. 2, p. 213) amazing. We know perfectly well that schizophrenia is a genetically inherited disease and thus we are no longer ignorant about its nature. We can put the aetiological hypotheses of Bateson, Laing, &c., into the dustbin straight away. Why Hirsch and Leff thought it necessary or useful to attempt to duplicate Singer and Wynne’s hypothesis that deviant communication is more frequent in the parents of schizophrenics than in the parents of neurotics I cannot imagine. Can a mock scientific study based on the esoteric Rorschach test have any meaning, even had the project itself been useful, which it was not ? It is within the experience of all of 1. 2. 3.
us
closely concerned
Carney, M. W. P., Sheffield, B. S. J. nerv. ment. Dis. 1970, 150, 404. Reynolds, E. H. Brain, 1968, 91, 197. Shulman, R. Can. psychiat. Ass. J. 1972, 17, 205.
hormone,
such as 3, 3’, 5’ T3 (reverse T3) is present in increased concentration and may prevent the expected
reduced thyroid-hormone levels.17 preliminary observations indicate that care is required in the interpretation of thyroid-hormone levels in seriously ill patients, since subnormal T4 as well as T3 T.S.H. response to
These
levels may
occur.
The question also arises whether
therapeutic intervention with exogenous T3 (or oral T.R.H.) might be justified since reversion of some of the metabolic changes which follow
M.I. may
improve prognosis.
Department of Materia Medica and Radioimmunoassay Unit, Stobhill General Hospital, Glasgow G21 3UW.
D. G. MCLARTY W. A. RATCLIFFE K. McCOLL D. STONE J. G. RATCLIFFE.
Committee Z-79 has found the U.S. Military Standard: Human Engineering Design Criteria for Military Systems, Equipment and Facilities, MIL-STD-1472B, Dec. 31, 1974, of very great use in the location, labelling, and safe design of controls and instruments. This valuable source was drawn to our attention by Mr Robert Cangelosi (Food and Drug Administration, Bureau of Medical Devices, 5600 Fishers Lane, Rockville, Maryland 20852), who, I am sure, would be happy to make copies available to engineers and others working to improve the safety of anaesthesia and other medical equipment. Mount Sinai School of Medicine, City University of New York, Fifth Avenue and 100th Street, New York, New York 10029,
L. RENDELL-BAKER.
U.S.A.
CURIOUS CURD SiR,—Concerning the letter from Dr Bennett and Dr Herman (June 28, p. 1430), the important point is that warm undiluted Jersey milk was given in appreciable quantity to an infant. Jersey milk is much richer than Friesian, which is now the commonest milk in the United Kingdom, as shown by the following compositional data (typical values per cent):
FOLATE-RESPONSIVE SCHIZOPHRENIA SIR,-Irefer to your interesting leader (June 7, p. 1283)
folate-responsive schizophrenia in which you suggest some patients may be deficient in methylenetetrahydrofolate. In the course of a retrospective survey1 of psychiatric inpatients with a low serum-folate at admission, a group given folate supplements virtually randomly were compared for a time in hospital with patients not so treated. The groups were comparable on age and sex, all had normal serum-Bl2 levels and were otherwise given conventional psychiatric treatment. The results were: on
that
Folate No.
The Jersey milk would form a large curd in the infant’s stomach, which would then by vomiting be forced up the oesophagus and so acquire the sausage shape depicted. It then became lodged at the back of the throat and so obstructed the trachea. This phenomenon is not confined to infants. Some years ago a chemical engineer drank a glassful of an experimentally concentrated milk (6/1) and this formed a tough curd in the stomach which took six months to disperse. Undiluted Jersey milk should never be taken in quantity by infants and adults with weak digestion. Milk which has been precurdled, as in yoghourt, and milk which has been predigested by pancreatin are quite safe in this respect since they do not form a coherent curd in the stomach. Reading, Berks.
J. G. DAVIS.
(days)
3 10 7
44 3 23-3 76-3
Schizophrenia Endogenous depression Organic psychoses ..
701 32-9 99-6
The folate-treated patients spent significantly less time hospital than those not given folate (Mann-Whitney u test, u=203; z=1-922; p=0-027 [one-tailed]), a difference not seen in the low-folate patients with other psychiatric diagnoses. Though factors other than clinical improvement may determine length of time in hospital, it is a stable criterion free from observer bias. As there is now good evidence of associations between folate deficiency and mental illness,2,3 there is a pressing need for further investigation of its possible aetiological role and a prospective double-blind trial of folic acid in low serum-folate patients with schizophrenia and other psychiatric conditions. Northwick Park Hospital,
SIR,-Anaestherists in recent years have otten spent some time in foreign countries obtaining training and experience. Dr Wilson (July 5, p. 35) emphasised the ever-present hazard posed by the dissimilar layouts of controls on anaesthetic apparatus between various countries and manufacturers. An example of one difficulty is the location and marking of the O2 flowmeter on anaesthetic gas machines. Many O2 controls in Europe are on the left and may be coloured white or blue (in Germany) whereas in the U.S. most machines have the O2 control on the right, and coloured green!I Dr Wilson did well to draw our attention to the extensive work that has been carried out in the aircraft industry and by the Armed Forces to reduce the hazard from misread instruments and controls. British Standards Institute Committee SGC 15 and A.N.S.I. Committee Z-79 are working on an I.S.O. draft standard intended to increase the safety and define the performance expected of anaesthetic gas machines.
Middlesex HA1 3UJ.
Chopra, I. J. J. clin. Invest. 1974, 54, 583.
10 8 12
in
DESIGN OF ANÆSTHESIA APPARATUS
17.
Non-folate Time of (days) patients No.
Time
of patients
Harrow,
M. W. P. CARNEY.
SCHIZOPHRENIA
SIR,-I found your leading article (Aug. 2, p. 213) amazing. We know perfectly well that schizophrenia is a genetically inherited disease and thus we are no longer ignorant about its nature. We can put the aetiological hypotheses of Bateson, Laing, &c., into the dustbin straight away. Why Hirsch and Leff thought it necessary or useful to attempt to duplicate Singer and Wynne’s hypothesis that deviant communication is more frequent in the parents of schizophrenics than in the parents of neurotics I cannot imagine. Can a mock scientific study based on the esoteric Rorschach test have any meaning, even had the project itself been useful, which it was not ? It is within the experience of all of 1. 2. 3.
us
closely concerned
Carney, M. W. P., Sheffield, B. S. J. nerv. ment. Dis. 1970, 150, 404. Reynolds, E. H. Brain, 1968, 91, 197. Shulman, R. Can. psychiat. Ass. J. 1972, 17, 205.
