1
208 ANNOTATIONS THE GLUTAMIC ACID OF TUMOUR PROTEINS Kögl and Erxleben 1 lately presented evidence that some of the amino-acids of malignant-tumour proteins are partially racemised and that the effect is greatest in the case of glutamic acid. These findings suggested an essential difference between the proteins of normal and of malignant tissues and enabled hypotheses to be put forward regarding the mechanism of malignant change. Special importance therefore attaches to a communication from Chibnall and his collaborators, II who have sought to confirm the new observations. They have hydrolysed proteins derived from Crocker mouse sarcomas, a human carcinoma of the bronchus and a human carcinoma from the neck, and have separated the dicarboxylic-acid fraction by a modi- fication of the calcium-salt method of Foreman ; and in each case the glutamic-acid hydrochloride ultimately isolated in good yield showed the optical rotation characteristic of the usual 1( +) glutamic-acid hydrochloride. To these English findings Kögl and Erxleben reply 8 that the method of fractionation employed by Chibnall may not lead to the eventual isolation of partially racemised glutamic-acid hydro- chloride if this is present. They emphasise that there is an essential difference in the solubilities of the two forms of glutamic acid, both as the calcium salt and as the hydrochloride, and state that the d-form has a greater . solubility than the l-form. Consequently they consider that only the 1-form would have been isolated under the conditions used by the London investigators. In an attempt to confirm this, they added known amounts of d-glutamic acid to protein hydrolysates from normal tissues-which should contain only l-glutamic acid-the mixture being then submitted to fractionation via the calcium salts. The glutamic-acid hydrochloride they isolated in this way had the normal rotation. Kögl and Erxleben further say that they have now succeeded in isolating d-glutamic acid itself from the partially racemised hydrochlorides obtained from Brown-Pearce tumour, which indicates that the low rotation of these latter products cannot have been due to the presence of impurities with a rotation of the opposite sign. A further statement from Chibnall and his colleagues will be awaited with interest. VASODILATOR DRUGS IN RAYNAUD’S DISEASE THE knowledge that Raynaud’s disease results from a spasm of the digital arteries encourages the constant hope that a suitable vasodilator drug may be found to relieve it. The perfect drug for the purpose would maintain an adequate blood-supply to the hands for many hours even though they were meanwhile exposed to cold; it would have no undesirable effects on other parts of the body, and it would be easy to administer. Nitrites have too transitory an action, as also have the acetylcholine derivatives unless administered by the cumbersome and somewhat difficult method of electrolysis ; and recently 4 papaverine hydrochloride has been advocated, though to be effective it must be injected intra- venously. The value of all such complicated forms of 1. Kögl, F., and Erxleben, H., Hoppe-Seyl Z. 1939, 258, 57 ; see Lancet, May 6, 1939, pp. 1049 and 1080. 2. Chibnall, A. C., Rees, M. W., Tristram, G. R., Williams, E. F., and Boyland, E., Nature, Lond. July 8, 1939, p. 71. 3. Kögl and Erxleben, Ibid, July 15, p. 111. 4. Mulinos, M. G., Shulman, I., and Mufson, I., Amer. J. med. Sci. June, 1939, p. 793. treatment is questionable, because the patient is apt to decide that she prefers cold fingers to a very frequent attendance on her doctor for intravenous or electrical treatment. It has also been shown 5 that the simple procedure of warming the body-for example, in a hot bath-increases blood-flow in the hands just as effectively as iontophoresis with drugs. The hot bath serves at least as a convenient control in judging the value of the newer, more complicated and expensive methods. " HEALTH FOR 7,500,000 PEOPLE " New York city is the largest health unit in the world, for though England’s metropolis contains a somewhat larger population its health services are divided whereas those of Greater New York were unified by charter in 1901, when they were placed under a board of health consisting at present of seven members, five of whom are medical men. The American system of public-health administration differs considerably from ours and formerly was subject to political influences, but of recent years the system has been made much more stable and in New York especially the machinery is now as efficient as any in the world. A full account of the method of health government is given in the report of the commissioner, Dr. John L. Rice, for 1937, which contains a review of progress over the five years 1934-38. During this period the cost of the service has varied from 4¼ to 5 million dollars annually, but the New York citizen does not grudge the money, and since La Guardia has been mayor the success of the department has been so great as to bring conviction that money spent on health is soundly invested. The death-rate of New York in 1937 was 10·4 ; the infantile mortality dropped steadily from 53 in 1933 to 44 in 1937 ; tuberculosis mortality (per 100,000) fell from 64 to 57, and maternal mortality (per 1000 births) from 6 to 4. The last rate is computed somewhat differently from ours and the New York figure of 4 is about equal to a London rate of 3. The five- year period has been one of rapid development in the health programme ; the city is divided into 30 districts of which, at the end of 1937, two-thirds were completely organised. Though the Americans have a legal health code even more complicated than ours, they use it less. " Modern public-health admini- strations," Dr. Rice remarks, " makes relatively little use of police measures and carries on most of its work through health education." New York in fact claims to be the pioneer of educating people to look after their own health rather than trying to enforce health by legislation-and it may be granted that its health propaganda has been remarkably successful. Two points in the American system which are superior to ours are the efficiency of the laboratories for clinical diagnosis, especially in connexion with the differentiation of types of pneumococcus, and the length of the list of diseases compulsorily notifiable. Three groups of diseases trouble New York more severely than they do London-the pneumonias, diabetes, and heart disease in early middle age. In 1937 pneumonia was charged with 6504 deaths in New York against London’s 3477 and diabetes with 2669 against London’s 655. In New York all foetal deaths are reportable ; of 4802 abortions notified to the department in 1937 some 25 per cent. were embryos 5. Montgomery, H., Holling, H. E., and Friedland, C. K., Ibid, 1938, 195, 794.

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208

ANNOTATIONS

THE GLUTAMIC ACID OF TUMOUR PROTEINS

Kögl and Erxleben 1 lately presented evidence thatsome of the amino-acids of malignant-tumour proteinsare partially racemised and that the effect is greatestin the case of glutamic acid. These findings suggestedan essential difference between the proteins of normaland of malignant tissues and enabled hypotheses tobe put forward regarding the mechanism of malignantchange. Special importance therefore attaches to acommunication from Chibnall and his collaborators, II

who have sought to confirm the new observations.They have hydrolysed proteins derived from Crockermouse sarcomas, a human carcinoma of the bronchusand a human carcinoma from the neck, and haveseparated the dicarboxylic-acid fraction by a modi-fication of the calcium-salt method of Foreman ;and in each case the glutamic-acid hydrochlorideultimately isolated in good yield showed the opticalrotation characteristic of the usual 1( +) glutamic-acidhydrochloride. To these English findings Kögl andErxleben reply 8 that the method of fractionationemployed by Chibnall may not lead to the eventualisolation of partially racemised glutamic-acid hydro-chloride if this is present. They emphasise that thereis an essential difference in the solubilities of the twoforms of glutamic acid, both as the calcium salt andas the hydrochloride, and state that the d-form has agreater . solubility than the l-form. Consequentlythey consider that only the 1-form would have beenisolated under the conditions used by the Londoninvestigators. In an attempt to confirm this, theyadded known amounts of d-glutamic acid to proteinhydrolysates from normal tissues-which shouldcontain only l-glutamic acid-the mixture being thensubmitted to fractionation via the calcium salts. Theglutamic-acid hydrochloride they isolated in thisway had the normal rotation. Kögl and Erxlebenfurther say that they have now succeeded in isolatingd-glutamic acid itself from the partially racemisedhydrochlorides obtained from Brown-Pearce tumour,which indicates that the low rotation of these latterproducts cannot have been due to the presence ofimpurities with a rotation of the opposite sign.A further statement from Chibnall and his colleagueswill be awaited with interest.

VASODILATOR DRUGS IN RAYNAUD’S

DISEASE

THE knowledge that Raynaud’s disease resultsfrom a spasm of the digital arteries encourages theconstant hope that a suitable vasodilator drug maybe found to relieve it. The perfect drug for thepurpose would maintain an adequate blood-supplyto the hands for many hours even though they weremeanwhile exposed to cold; it would have no

undesirable effects on other parts of the body, and itwould be easy to administer. Nitrites have tootransitory an action, as also have the acetylcholinederivatives unless administered by the cumbersomeand somewhat difficult method of electrolysis ; and

recently 4 papaverine hydrochloride has been advocated,though to be effective it must be injected intra-

venously. The value of all such complicated forms of

1. Kögl, F., and Erxleben, H., Hoppe-Seyl Z. 1939, 258, 57 ;see Lancet, May 6, 1939, pp. 1049 and 1080.

2. Chibnall, A. C., Rees, M. W., Tristram, G. R., Williams, E. F.,and Boyland, E., Nature, Lond. July 8, 1939, p. 71.

3. Kögl and Erxleben, Ibid, July 15, p. 111.4. Mulinos, M. G., Shulman, I., and Mufson, I., Amer. J. med.

Sci. June, 1939, p. 793.

treatment is questionable, because the patient is aptto decide that she prefers cold fingers to a veryfrequent attendance on her doctor for intravenous orelectrical treatment. It has also been shown 5 thatthe simple procedure of warming the body-forexample, in a hot bath-increases blood-flow in thehands just as effectively as iontophoresis with drugs.The hot bath serves at least as a convenient controlin judging the value of the newer, more complicatedand expensive methods.

" HEALTH FOR 7,500,000 PEOPLE "

New York city is the largest health unit in theworld, for though England’s metropolis contains asomewhat larger population its health services aredivided whereas those of Greater New York wereunified by charter in 1901, when they were placedunder a board of health consisting at present ofseven members, five of whom are medical men. TheAmerican system of public-health administrationdiffers considerably from ours and formerly wassubject to political influences, but of recent yearsthe system has been made much more stable andin New York especially the machinery is now as

efficient as any in the world. A full account of themethod of health government is given in the reportof the commissioner, Dr. John L. Rice, for 1937,which contains a review of progress over the fiveyears 1934-38. During this period the cost of theservice has varied from 4¼ to 5 million dollars annually,but the New York citizen does not grudge the money,and since La Guardia has been mayor the success ofthe department has been so great as to bring convictionthat money spent on health is soundly invested. Thedeath-rate of New York in 1937 was 10·4 ; the infantilemortality dropped steadily from 53 in 1933 to 44 in1937 ; tuberculosis mortality (per 100,000) fell from64 to 57, and maternal mortality (per 1000 births)from 6 to 4. The last rate is computed somewhatdifferently from ours and the New York figure of4 is about equal to a London rate of 3. The five-year period has been one of rapid development in thehealth programme ; the city is divided into 30districts of which, at the end of 1937, two-thirds werecompletely organised. Though the Americans havea legal health code even more complicated than ours,they use it less. " Modern public-health admini-strations," Dr. Rice remarks, " makes relatively littleuse of police measures and carries on most of its workthrough health education." New York in factclaims to be the pioneer of educating people to lookafter their own health rather than trying to enforcehealth by legislation-and it may be granted that itshealth propaganda has been remarkably successful.Two points in the American system which are

superior to ours are the efficiency of the laboratoriesfor clinical diagnosis, especially in connexion with thedifferentiation of types of pneumococcus, and thelength of the list of diseases compulsorily notifiable.Three groups of diseases trouble New York moreseverely than they do London-the pneumonias,diabetes, and heart disease in early middle age. In1937 pneumonia was charged with 6504 deaths inNew York against London’s 3477 and diabetes with2669 against London’s 655. In New York all foetaldeaths are reportable ; of 4802 abortions notified tothe department in 1937 some 25 per cent. were embryos

5. Montgomery, H., Holling, H. E., and Friedland, C. K., Ibid,1938, 195, 794.