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D R BANGHAM

Publications and source records attributed to D R BANGHAM.

At least 19 recordsLinked to original sources

THE SECOND INTERNATIONAL STANDARD FOR CHORIONIC GONADOTROPHIN.

As stocks of the first International Standard for Chorionic Gonadotrophin were running low, the WHO Expert Committee on Biological Standardization authorized the National Institute for Medical Research, London, in 1960 to proceed with arrangements to replace it. This paper describes the nature and handling of the proposed replacement material, its assay by nine laboratories in six countries, and its establishment as the second International Standard for Chorionic Gonadotrophin, with a defined potency of 5300 International Units per ampoule. The International Unit of Chorionic Gonadotrophin is defined as the activity contained in 0.001279 mg of the second International Standard.

Biological Assay↗

THE SECOND INTERNATIONAL STANDARD FOR PROLACTIN.

In 1953 the WHO Expert Committee on Biological Standardization asked the National Institute for Medical Research, London, to collect and study suitable material to replace the First International Standard for Prolactin, stocks of which were running low. This paper reports the nature and handling of the proposed replacement material, its potency as determined by comparison with the First International Standard by international collaborative assay, and its establishment as the Second International Standard for Prolactin, with a defined potency of 22 International Units per mg. The International Unit of Prolactin is defined as the activity contained in 0.04545 mg of the Second International Standard.

Animals↗

The Third International Standard for Corticotrophin.

At its meeting in September 1957, the WHO Expert Committee on Biological Standardization agreed with the recommendation of the International Conference on Corticotrophin, held in July 1957, that a new international standard for corticotrophin should be set up, since the Second International Standard was made from crude material and was unsuitable for the assay of the purer preparations of corticotrophin now in general clinical use. In this paper, the authors describe the steps taken to establish the Third International Standard for Corticotrophin, from the preparation and international collaborative assay of the new material to the choice of the "subcutaneous assay" for deriving the potency. The clinical and pharmacological implications of this choice are discussed.Since the preparation, characterization and exact quantitative assay of standards for corticotrophin are so difficult, several batches of approximately 3500 ampoules were prepared in a similar way from the same material to serve as an international Working Standard. Samples from two batches were included in the collaborative assay and found to have the same potency as the Third Standard. Sufficient ampoules of the Working Standard are available for use as national and laboratory standards.

Adrenocorticotropic Hormone↗

International Reference Preparation for vitamin B12.

The International Reference Preparation for Vitamin B(12) was prepared in tablet form from a mixture of anhydrous cyanocobalamin and sodium chloride. In an international collaborative study, in which eleven laboratories participated, this preparation was examined qualitatively and quantitatively by spectrophotometric and microbiological methods. It was concluded that the International Reference Preparation is substantially pure and has a potency of 9.3 mug of cyanocobalamin per 20 mg of tablet.

Vitamin B 12↗

The Fourth International Standard for insulin.

The composition, analysis and distribution of crystalline insulin for the Fourth International Standard for Insulin is described. In an international collaborative assay 20 laboratories compared this Standard with the Third International Standard, and the statistical analysis of the results is reported.On the basis of the results the Fourth International Standard for Insulin is established with a potency of 24.0 IU/mg. The International Unit is thus defined as the activity contained in 0.04167 mg of the Standard preparation.

Biological Assay↗

The Second International Standard for heparin.

The Second International Standard for Heparin is a hygroscopic powder which was obtained by purifying and drying a batch of commercial beef heparin powder. In an international collaborative assay it was compared with the First International Standard, which it will now replace. As a result of the assay the seven participating laboratories agreed that the potencies of the two preparations did not differ significantly and the definition of the International Unit for Heparin remains unchanged as the activity contained in 0.0077 mg of the Second International Standard for Heparin.

Animals↗

The international pyrogen reference preparation.

In accordance with authorization given by the WHO Expert Committee on Biological Standardization in 1950, the National Institute for Medical Research, London, obtained samples of two bacterial pyrogens and arranged for an international study of their pyrogenic properties in rabbits. The results of this study showed that the dose response curves were flat and there was a large variation in response within and between colonies of rabbits.It was agreed that some reference preparation was needed. There was no evidence to indicate the most suitable type of preparation, and there was insufficient as regards either of the two which had been studied. It was therefore decided to make available a quantity of a preparation of the O somatic antigen of Shigella dysenteriae for the International Reference Preparation. Such a substance has been obtained for this purpose and the distribution and characteristics are described.

Animals↗

Third international standard for posterior pituitary; re-named third international standard for oxytocic, vasopressor and antidiuretic substances in 1956.

In October 1955, stocks of the Second International Standard for Posterior Pituitary were running low and the Department of Biological Standards of the National Institute for Medical Research, London, was asked to proceed with the arrangements for an international collaborative assay of material for the Third Standard. A single 142-g batch of posterior-pituitary-lobe powder was obtained and distributed in ampoules, in approximately 30-mg quantities. Samples were sent to 19 laboratories in 10 countries. In all, 185 assays were carried out, 122 for oxytocic activity, 53 for vasopressor activity and 10 for antidiuretic activity.On the basis of the results, which were analysed statistically at the National Institute for Medical Research, it was agreed that the potency of the Third Standard (re-named International Standard for Oxytocic, Vasopressor and Antidiuretic Substances in 1956, in view of the recent synthesis of oxytocin and vasopressin) should be expressed as 2.0 International Units per milligram. The International Unit therefore remains unchanged as 0.5 mg of the dry powder.

Biological Assay↗