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Biomedical subjects

I Batty

Publications and source records attributed to I Batty.

At least 19 recordsLinked to original sources
PubMed1988

Dopamine receptor stimulation does not affect phosphoinositide hydrolysis in slices of rat striatum.

The effect of dopamine receptor stimulation on the accumulation of labelled inositol phosphates in rat striatal slices under basal and stimulated conditions was examined following preincubation with [3H]inositol. Incubation of striatal slices with the selective D-1 agonist SKF 38393 or the selective D-2 agonist LY 171555 for 5 or 30 min did not affect the basal accumulation of labelled inositol mono-, bis-, tris-, and tetrakisphosphate. Resolution by HPLC of inositol trisphosphate into inositol-1,3,4-tris-phosphate and inositol-1,4,5-trisphosphate isomers revealed that under basal conditions dopamine did not influence the accumulation of inositol-1,4,5-trisphosphate. Depolarisation evoked by KCl, or addition of the muscarinic receptor agonist carbachol, produced a marked increase in the accumulation of labelled inositol phosphates in both the presence and absence of lithium. Addition of dopamine did not reduce the ability of KCl or carbachol to increase inositol phospholipid hydrolysis. In the presence of lithium, dopamine (100 microM) enhanced KCl-stimulated inositol phospholipid hydrolysis, but this effect appears to be mediated by alpha 1 adrenoceptors because it was blocked by prazosin. SKF 38393 (10 microM) or LY 171555 (10 microM) also did not affect carbachol-stimulated inositol phospholipid hydrolysis. These data, in contrast to recent reports, suggest that striatal dopamine receptors do not appear to be linked to inositol phospholipid hydrolysis.

Animals↗
PubMed1987

Lithium inhibits muscarinic-receptor-stimulated inositol tetrakisphosphate accumulation in rat cerebral cortex.

The effects of Li+ on carbachol-stimulated phosphoinositide metabolism were examined in rat cerebral-cortex slices labelled with myo-[2-3H]inositol. The muscarinic agonist carbachol evoked an enhanced steady-state accumulation of [3H]inositol monophosphate ([3H]InsP1), [3H]inositol bisphosphate ([3H]InsP2), [3H]inositol 1,3,4-trisphosphate ([3H]Ins(1,3,4)P3), [3H]inositol 1,4,5-trisphosphate ([3H]Ins(1,4,5)P3) and [3H]inositol tetrakisphosphate ([3H]InsP4). Li+ (5 mM), after a 10 min lag, severely attenuated carbachol-stimulated [3H]InsP4 accumulation while simultaneously potentiating accumulation of both [3H]InsP1 and [3H]InsP2 and, at least initially, of [3H]Ins(1,3,4)P3. These data are consistent with inhibition of inositol mono-, bis- and 1,3,4-tris-phosphate phosphatases to different degrees by Li+ in brain, but are not considered to be completely accounted for in this way. Potential direct and indirect mechanisms of the inhibitory action of Li+ on [3H]InsP4 accumulation are considered. The present results stress the complex action of Li+ on cerebral inositol metabolism and indicate that more complex mechanisms than are yet evident may regulate this process.

Animals↗
PubMed1986

The use and standardization of multicomponent veterinary vaccines.

Farming practices necessitate the use of combined vaccines for the protection of sheep, cattle and pigs. Multi-component Clostridial vaccines have been available in veterinary medicine since the late 1950s and are standardized on the basis of antibody responses in small animals and/or challenge tests. The development of new vaccines against respiratory and enteric diseases has posed a number of standardization problems as small animal models are not readily available and antibody responses do not necessarily correlate with protection. Approaches to the standardization and use of these components will be discussed.

Animals↗
PubMed1985

Differential effects of lithium on muscarinic receptor stimulation of inositol phosphates in rat cerebral cortex slices.

The accumulation of labelled inositol mono-, bis-, and trisphosphate in rat cerebral cortex slices was examined following preincubation with [3H]inositol. The muscarinic receptor agonist carbachol produced a rapid and sustained increased accumulation of each labelled inositol phosphate both in the presence and absence of 5 mM lithium. Lithium potentiated carbachol-stimulated accumulation of inositol monophosphate (EC50 0.5 mM) and inositol bisphosphate (EC50 4 mM) in a concentration-dependent manner. However, exposure to lithium in the presence of the muscarinic agonist produced a concentration- and time-dependent inhibition of inositol trisphosphate accumulation that was not related to receptor desensitisation. Although the present data do suggest that polyphosphoinositides are substrates for agonist-stimulated phospholipase C in brain, these results may not be entirely consistent with the production of inositol mono- and bisphosphate through inositol trisphosphate dephosphorylation. Furthermore, these data suggest site(s) additional to inositol monophosphatase that are affected by lithium.

Animals↗
PubMed1983

Quality control of fluorescein isothiocyanate-labeled reagents.

Fluorescein-labeled reagents are not amenable to the same precision of definition as are chemical substances. Nonetheless extensive experimental evidence shows that certain preparative requirements and selected measurable chemical parameters of the product are of considerable predictive value in determining whether a reagent will be suitable in use. Adherence to these criteria and their continuous reappraisal combined with performance assessment and information on stability are all essential to ensure that reagents are of a quality acceptable to laboratory workers and legislative bodies. The need for manufacturers to document each procedural step and record the results is an essential element of good manufacturing practice now imposed by regulatory bodies. All reputable manufacturers adhere to these requirements, which serve not only to maintain standards but also to form a basis for corrective action.

Antibodies, Anti-Idiotypic↗
PubMed1983

Active and passive immunization to protect against antibiotic associated caecitis in hamsters.

The administration of clindamycin to hamsters induces a lethal enterocolitis as a consequence of toxins produced in the alimentary tract by Clostridium difficile. The lethal and cytopathic effects of C. difficile toxins are neutralized in vitro by C. sordellii antitoxin and hamsters may be protected against clindamycin induction of caecitis by passive immunization using C. sordellii antitoxin. To examine active immunization using C. difficile and C. sordellii toxoids, groups of male and female Syrian hamsters were immunized on two occasions and challenged by parenteral clindamycin. A concentrated C. difficile toxoid protected 90% of females and 78% of males; the degree of protection per group decreased with dilution of the toxoid used for immunization. A similar degree of protection was observed in female hamsters immunized with a bivalent vaccine prepared from the partially purified toxins A and B of C. difficile. Immunization using a C. sordellii toxoid protected between 100 and 25% of females per group and between 50 and 12.5% of males per group.

Animals↗
PubMed1980

Observations on vaccine and post-infection immunity in contagious equine metritis.

The vaccination of four ponies on two occasions with a formolised culture of Haemophilus equigenitalis produced a high circulating antibody titre to the organism in each pony. Three out of four vaccinated and all of three unvaccinated ponies developed typical symptoms of contagious equine metritis (CEM) when subsequently challenged with a vaginal exudate containing H equigenitalis. Similarly, three ponies which had previously been infected with H equigenitalis and which had recovered spontaneously also developed contagious equine metritis when rechallenged with the organism. The clinical and bacteriological symptoms in the vaccinated ponies and in the rechallenged ponies were less severe than those observed in the unvaccinated ponies but H equigenitalis was still recovered 17 days after challenge from the three vaccinated ponies which had developed CEM. The vaccinated pony which remained free from infection did not exhibit the highest circulating antibody titre of the vaccinates before challenge.

Animals↗
PubMed1976

Progress in standardization: 4 immunological reagents.

The need for material standards in the field of clinical immunology, together with the mode of operation of the combined World Health Organization/International Union of Immunological Societies programme for the provision of such standards, are discussed. Attention is drawn to the importance of the use of International Units in reporting concentrations of complex constituents, e.g., immunoglobulins in body fluids, and to the availability of standard materials against which such components can be calibrated. The necessity for the standardization of nomenclature is also emphasized.

Allergy and Immunology↗