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Biomedical subjects

F T Perkins

Publications and source records attributed to F T Perkins.

At least 37 records · Page 2Linked to original sources
PubMed1975

Biological standards and pharmacopoeias.

The use of standards in the control of biological substances is of particular importance because the potency of such substances cannot be adequately determined by physical or chemical means. For these substances, therefore, it is necessary to compare the activity or potency of a given quantity with that of a similar quantity of a standard or reference preparation to which a unitage has been assigned. In order to eliminate as far as possible the inherent variables in biological tests, especially in tests involving animals, the comparison between the standard and the unknown must be made in a single test. Furthermore it is essential that the biological activity of the standard has the same properties as those products for which the standard is used as a control. The master standards are the International Standards held by the World Health Organization and it is necessary to establish European or National Standards calibrated in International Units in order to conserve the stocks of the master standards. Criteria for the quality of preparations suitable as standards will be considered and some examples of their use will be presented.

Biological Products↗
PubMed1973

Long-term survival of HeLa tumours in mice treated with antilymphocyte serum.

During studies of the ability of antilymphocyte serum (ALS) to suppress the immune mechanism of mice and thereby allow HeLa cells to grow into a large tumour in the mice, it was observed that many tumours continued to grow even after the ALS treatment had been stopped and full immunological competence of the mice had returned. The HeLa cells of such tumours appeared to be unchanged in their ability to induce further tumours in ALS treated mice to which they were transferred and, furthermore, the mice which were carrying such tumours in the presence of immunological competence were able to reject additional injections of HeLa cells or other human tumour cells. The four possible explanations for this phenomenon, (i) depression of cellular response; (ii) local reaction at the graft site; (iii) the presence of a blocking factor; and (iv) the elevation of the humoral response, have been investigated.

Animals↗
PubMed1973

Standardization of diagnostic materials. 5. Tissue culture media and reagents.

The various factors that affect the growth of cell cultures in vitro are considered and suggestions are made as to where the standardization of components would help to provide more uniform products. The manufacture of powdered media in bulk and the establishment of cell banks have been major advances, but much research is needed for the standardization or replacement of serum.

Animals↗
PubMed1972

WHO collaborative studies on poliovirus type 3 strains isolated during the 1968 poliomyelitis epidemic in Poland.

In 1968 in Poland an extensive outbreak of poliomyelitis, caused by type 3 poliovirus, began about four months after small vaccine trials with the Leon 12a(1)b (Sabin) and USOL-D bac vaccine strains had been carried out. Because of the temporal association, and because the first cases appeared in the province in which the USOL-D vaccine trial was carried out, a detailed investigation of the strains isolated from cases in the epidemic was made in four laboratories in an attempt to determine whether they were related to the two vaccine strains or to a "wild" strain. All the studies were made under code. The rct marker was of no help in determining the relationship of the epidemic strains to the vaccine strains. The McBride test and the elution marker test clearly separated the Leon 12a(1)b strains from those from the cases, but were incapable of detecting whether the epidemic strains were related to the USOL-D bac strain or to wild type 3 strains. Thus the studies did not provide valid information on the origin of the epidemic.

Child↗
PubMed1971

The British reference preparation for influenza virus haemagglutinin.

The two methods for measuring the haemagglutinin content of an influenza virus suspension are the haemagglutinating (HA) and chick cell agglutinating (CCA) techniques and both measure the same biological activity. With the establishment of an international reference preparation for influenza virus haemagglutinin (type A), however, it seems logical to express the haemagglutinin content of influenza vaccines in international units. Accordingly a collaborative study was arranged in order to obtain agreement on the number of units to be assigned to a British reference preparation for influenza haemagglutinin. It was agreed that the preparation contains 190 i.u. per ampoule and 1 i.u. is contained in 0.0622 mg. of the dried material.

Animals↗