CHANNON AND MARRIAN [1926] examined the unsaponifiable fraction of pig liver primarily with a view to investigating the possible presence in liver of the unsaturated hydrocarbon squalene. Their results showed that, although squalene was not present, pig liver contained a highly unsaturated hydrocarbon of apparently very high molecular weight, and some evidence was obtained that this hydrocarbon was of terpenoid nature. The presence of the hydrocarbon was deduced from the ready preparation of an insoluble bromide and of a hydrochloride from fractions of the unsaponifiable matter into which the more unsaturated constituents had been concentrated. Analysis of the former compound showed that it was the bromide of an unsaturated hydrocarbon. The hydrochloride however was contaminated by an impurity which could not be removed and the mean values for the C, H and Cl analyses totalled no more than 98-71 %.The investigation of the unsaturated hydrocarbon did not progress further, because it could not be obtained in pure form; concentrates of it decomposed when distilled in.vacuo, and regeneration by dehalogenation of its halogen compounds was unsatisfactory. Further, deductions as to the molecular formula of the substance from consideration of the analyses of the halogen compounds could not be made, for the molecular weight of the hydrocarbon was unknown, nor could those of the bromide and hydrochloride be determined on account of their properties. The great advances which have been made in knowledge of the chemical nature of the higher terpenes in the last few years and the increasing realisation of the biochemical importance of these substances suggested that further investigation of the liver compound was desirable. It seemed not inconceivable that this compound might be concerned with the metabolism of carotene and vitamin A, or possibly with that of cholesterol, for the feeding of squalene to rats causes a noteworthy increase in the amount of cholesterol in the liver [Channon, 1926]. This paper therefore contains an account of attempts to obtain the unsaturated hydrocarbon of mammalian liver in pure form as a preliminary to its chemical investigation. Sufficient progress has been made to lead us to publish the results so far obtained, for further advance cannot be made until more material is available, the preparation of which will entail a considerable delay. EXPERIMENTAL.Preparation of the unsaponiftable fraction.Pig liver, having been shown to be richer in the hydrocarbon than that of the other mammals investigated, was again used as the starting material. The method adopted for the preparation of the unsaponifiable matter was essentially that used by Channon and Marrian [1926]. The pig liver was obtained from the

Diabetes mellitus occurring in the neonatal period has so seldom been reported that the following case seems worthy of record.The patient was a female child, aged twenty-five days, born of healthy parents, with no family history of diabetes. The mother, aged twenty-four years, had had two previous pregnancies; in both cases birth was premature. The first child is alive and well, aged two years; the second died within a few hours of birth.The third child, the subject of this communication, was also born prematurely, in the twenty-eighth week of pregnancy. This apparently was normal in every respect and labour was easy and spontaneous. At birth the baby seemed healthy, cried immediately, was quite vigorous and sucked well. She is said to have weighed only 3 lb. In spite of apparently adequate breast feeding, the child failed to thrive and became weaker and at one week she was unable to suck and was put on to spoon feeding, at first on breast milk and later on a sweetened, condensed milk. She never took well, however, being unable to swallow more than 2 to 3 teaspoonfuls at each feed. She became extremely weak and emaciated, and at twenty-five days was admitted to hospital, having been vomiting persistently during the two previous days.On admission, the child was grossly emaciated and dehydrated and weighed only 1-02 kgm. Respiration was shallow, the temperature subnormal, the pulse imperceptible and the heart sounds almost inaudible. She was not deeply comatose as she responded feebly to painful stimuli, but she could not suck and could only swallow with difficulty. The umbilicus was clean, no abnormal physical signs were detected in chest or abdomen and there was no otitis media. A tentative diagnosis was made of prematurity with marked feebleness.The child was wrapped in cotton-wool and kept under an electric blanket. All disturbance was avoided; frequent small feeds were given by pipette and these were swallowed with difficulty but retained.Several hours after admission a specimen of urine was obtained and was found to contain albumin: it gave a strong reduction of Benedict's solution and the phenyl glucosazone test was positive. The blood-sugar was 542 mgm. per cent. The child died shortly after this observation was made and before any attempt could be made to treat the diabetic condition. 189 on 12 May 2018 by guest. Protected by copyright.

BENcE-JONES protein, which is characterized by precipitation from solution at low temperatures (45-50') and resolution of the coagulum on boiling, is excreted in the urine in about 70 % of the cases of multiple myelomatosis.and occasionally also in allied diseases of the bone marrow and blood-forming organs. Of some seven hundred papers on myelomatosis which have appeared since Bence-Jones [1848] first noted the excretion of a peculiar substance in a case of 'mollities ossium', relatively few have dealt in detail with the chemistry of the protein. The purpose of the present communication is to give the results of an analysis of the amino-acid content of a sample of Bence-Jones protein obtained from a case of multiple myelomatosis which recently came under observation in the terminal stages, in the Tropical Ward of the Royal Infirmary, Liverpool; other features of the case will be-discussed elsewhere. The urine, which was collected daily under toluene for about 3 weeks immediately before the death of the patient, showed the typical reactions of ience-Jones protein and was free from normal plasma proteins. After storage at 00 the different samples were filtered and mixed;, part was reserved for isolation of the protein in soluble form, and the rest was coagulated for analysis. EXPERIMENTAL As the amount of material for amino-acid analysis was small, attention was confined to colorimetric and small scale isolation methods. No attempt was made to apply the general solubility method devised by Bergmann & Stein [1939]. All the colorimetric analyses were carried out by means of a Hilger 'Spekker' Absorptiometer. In using this instrument the drum reading obtained by comparing the coloured solution with the appropriate blank is referred to a calibration curve similarly prepared from standard solutions of the pure constituent being estimated. The light filter is so chosen as to give maximum sVnsitivity. Solutions for the 1 cm. cups should be made up to 10 ml. All the reagents used were of A.R. quality or were purified by standard procedures and were freshly made up in solution. 'Blank tests were carried out where necessary and all the procedures were submitted to preliminary test against standard protein preparations. Unless otherwise stated, the results obtained with Bence-Jones protein are the mean of two or more determinations and refer to the moisture-and ash-free material. Preparation of Bence-Jones protein. The pH of the urine was adjusted with acetic acid to the point of maximum precipitation in the cold and the coagulation completed by heating to 60°for 30 min. Exhaustive washing of the protein by centrifuging was carried out by allowing it to stand 1-2 days in the wash liquor and repeating this several times afresh-first with very dilute acetic acid, then Research Fellow, Medical Research Council. (433) water, water at 600, aqueous alcohol, absolute alcohol, and finally light petroleum twice overnight.' The latter was repeated by extracting twice for a day in a Soxhlet apparatus and the protein was then air-dried ...

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The accepted periodate method for the determination of glycerol has come under review by the International Organisation for Standardisation (Sub-committee ISO/TC47/GT2) and certain modifications have been suggested with regard to the different pH end-points for the sample and blank and the possible loss of formic acid from the system by volatilisation. The present paper summarises the view of the U.K. delegates to ISO/TC47/GT2, which are:(i) The choice of pH about 8.0 for the sample is justified on the ground that it contains formic acid in addition to strong acids. The blank, which contains only strong acids, should, on general grounds and by calculation, be titrated to pH 7-0. The use of pH 6.5 instead of 7.0 for the blank is an empirical correction designed to compensate for some lack of stoicheiometry or other bias in the procedure and to bring the results into agreement with those obtained by independent moisture and specific gravity determinations. This "correction" amounts to 0-03 per cent.(ii) There is a potential loss of formic acid by volatilisation from the system (estimated variously to be equivalent to 0.01 to 0.04 per cent. of glycerol), which partly explains the apparent lack of stoicheiometry.(iii) Modifications have been proposed to minimise this loss of formic acid and (by adding formate ions to both solutions) to unify the end-points a t or about pH 8.0. Unless these modifications lead to a pronounced improvement in reliability, it seems doubtful whether further extensive trials on an international basis would be justified.* This paper was written a t the suggestion of the British Standards Institution Committee CIC/6-Glycerol by two of its members who are also U.K. delegates to the Working Group on glycerol of the International Organisation for Standardisation (ISO/TC47/GT2). It therefore represents the current U.K. attitude on the problem of the determination of glycerol, which is a t present engaging the attention of ISO. 0 SAC and the authors.* It is recognised that inflexion point and equivalence point are not identical, but with strong electrolytes, as in the blank, the difference is negligible.6 * This is close to the figure of "about 0.370" given in B.S. 2621-5 : 1964 as the correction that results from using the pH end-points 6.5 and 8.1. I n our view the term "correction" should more properly be applied to the 0-03 per cent. difference that results from using pH 6.5 instead of 7-0 in the blank.

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