Biomedical subjects

B Pollock

Publications and source records attributed to B Pollock.

59 records · Page 4Linked to original sources

PubMed1976

Visually evoked potentials in cortical and subcortical brain structures of conscious rabbits with chronically implanted electrodes. Standardized normal values and the influence of some psychopharmacological agents on them.

By means of a modified and simplified surgical and implantation technique, standardized values for visually evoked potentials (EP) from 7 brain structures (caudate nucleus, posterior hypothalamus, mesencephalic reticular formation, intra-laminar thalamic nuclei, amygdala, dorsal hippocampus and visual cortex) are obtained. The importance of a careful selection of the animal material, constant test conditions and the selection of test parameters as a prerequisite for the assessment of psychotropic drugs is emphasized and discussed. As an example of the specific influence on visually evoked potentials in the above named brain structures, the effects of haloperidol and amytriptyline on latencies and amplitudes of the individual parameters of EPs are described. It is assumed that the method described can be of great assistance for investigation and classification of newly developed substances.

Amitriptyline↗

PubMed1975

Antigenic relationships of common rhinovirus types from disabling upper respiratory illnesses.

The frequency of the common cold has been though to be due to the existence of more than 89 different serologic types of rhinoviruses. However, in the civilian and military population studied in this area from 1962 through 1970, types 1A, 1B, 2, 23, 29, 30 and 31 accounted for 81 percent of 487 rhinoviruses isolated from individuals with respiratory illnesses. Antigenic relationships between these types and others have been demonstrated by neutralization in WI-38 cell cultures and by immunodiffusion. Types 1A and 1b, 2 and 49, 23 and 30, 29 and 44 and others are related. With specific animal antisera, heterotypic antibody titers are minimal. However, following natural infection in man with one of these related types, antibody responses to the other was almost equal to the homotype and could predictably provide cross-protection. Even with inactive T13 rhinovirus vaccine in man, protective levels of neutralizing antibody to T41 were produced. It is clear that the rates of rhinovirus colds would be greatly increased if more than 89 immunologic distinct types actually existed. An effective vaccine could be easily prepared by selection of a few appropriate types, such as 1A, 2, 23, 29 and 31.

Adolescent↗

PubMed1975

[A modified method for the determination of locations of chronically implanted electrodes in rabbit brains (author's transl)].

A fast and simple method is described for the localisation of tips of chronically implanted electrodes in the brain of rabbits which may be obtained--under standard conditions--by an intra-aortal injection of a 2% potassium-hexacyanoferrate-III solution. This method also facilitates histological preparations with a thickness of 5 mu only and thus permits a thorough morpho-pathological examination not only in the area of the electrode tips but in adjacent zones as well. The use of a buffered formalin solution also permits certain histochemical examinations to be made, for instance the determination of nucleic acids.

Animals↗

PubMed1972

Use of a clonal line of porcine kidney cell cultures for primary isolation and vaccine studies with adenoviruses.

The clonal line (Y15) of porcine kidney stable cells provided a recovery system for adenovirus T4 from specimens from adults with respiratory illnesses that was as sensitive as human embryo kidney cultures. Adenoviruses T7 from adults, and T1, 2, 3, and 5 from children could be readily isolated in porcine kidney cell cultures. The latter were useful for adenovirus vaccine studies in that infectivity titers of live virus vaccine and neutralization antibody responses after vaccination were equal to those obtained in human embryo kidney cultures.

Adenoviridae↗

PubMedDate not supplied

Immunisation with recombinant AMA-1 protects mice against infection with Plasmodium chabaudi.

The Plasmodium merozoite surface antigen apical membrane antigen-1 (AMA-1) has previously been shown to provide partial protection to Saimiri and rhesus monkeys immunised with recombinant Plasmodium fragile or parasite-derived Plasmodium knowlesi AMA-1, respectively. In the study reported here we have used the Plasmodium chabaudi/mouse model system to extend our pre-clinical assessment of an AMA-1 vaccine. We describe here the expression of the full-length Plasmodium chabaudi adami AMA-1 and the P. chabaudi adami AMA-1 ectodomain using both baculovirus and Escherichia coli. The ectodomain expressed in E. coli, which contained an N-terminal hexa-his tag, was purified by Ni-chelate chromatography and refolded in vitro in the presence of oxidised and reduced glutathione to generate intramolecular disulphide bonds. In a series of vaccine trials, in both inbred and outbred mice, highly significant protection was obtained by immunising with the refolded AMA-1 ectodomain. Protection was shown to correlate with antibody response and was dependent on intact disulphide bonds. Passive transfer of antibodies raised in rabbits against the refolded AMA-1 ectodomain was also protective. In view of this demonstration that E. coli expression of a soluble P. chabaudi AMA-1 domain can generate a vaccine that is effective in mice, we are pursuing a similar approach to generating a vaccine against P. falciparum for testing in human volunteers.

Animals↗