PubMed Health⌕ Search

Biomedical subjects

P J Carroll

Publications and source records attributed to P J Carroll.

15 recordsLinked to original sources
PubMed1992

Detection of entero- and verocyto-toxin genes in Escherichia coli from diarrhoeal disease in animals using the polymerase chain reaction.

Oligonucleotide primers were designed for the specific polymerase chain reaction (PCR) amplification of the enterotoxins STIa and LTI and of the verocytotoxins VT1 and VT2. All of 184 E. coli isolates from cases of diarrhoea from pigs, cattle and sheep gave identical toxin profiles by PCR and gene probe. Differentiation between VT2 and VT2v was achieved using two oligonucleotide primers pairs in PCR and showed that all of 34 VT2+ porcine isolates, of which 23 were 0138:K1, harboured VT2v whereas 20 VT2+ bovine and ovine isolates harboured VT2. No isolate harboured both VT2 polymorphs. Simplified methods for sample preparation for PCR were examined and showed that PCR was not inhibited by direct addition of broth culture to the reaction mixture.

Animals↗
PubMed1992

Conformational studies of muscarone analogues: X-ray analysis and molecular mechanics calculations.

The X-ray structure of muscarone analogues 3 and 4 was determined and compared with that of muscarone (1, iodide and picrate salts), muscarine 2, dioxolane 5, oxathiolane 6, and tetrahydrofuran 7. In order to better define the pharmacological stereoselectivity of muscarone, the conformational profiles of compounds 1, 2, 3, and 5 were analyzed using Allinger's MM2(85) program or, in the case of 4, by 1H NMR spectroscopy. The conformation of the ring in 1 proved similar to that of the other derivatives. MM2 calculations predicted a preferred gauche arrangement of the side chain for 1 and its analogues; such an arrangement was also observed in the solid state of muscarone picrate. Thus, the antiperiplanar arrangement reported for crystalline muscarone iodide appears to be due to crystallographic packing forces. As a consequence, the rationalization of the pharmacological profile of 1 based on the antiperiplanar arrangement is now highly questionable. The lack of stereoselectivity of 4 can be attributed to the absence of a stereocenter at C-2 whereas, in our opinion, there are currently no sound explanations for the low values of eudismic ratios for the muscarone enantiomers.

Molecular Conformation↗
PubMed1991

Enhanced expression of 987P (F6) fimbrial adhesin by cultured enterotoxigenic Escherichia coli.

The expression of the 987P fimbrial adhesin by strains of enterotoxigenic Escherichia coli was enhanced and, in some cases, restored by passaging the organisms through Craigie's tubes. In contrast, the fimbrial adhesins K99, K88 and F41 were not optimally expressed in this medium. The results suggest that Craigie's tubes should be used for the optimum expression of 987P.

Adhesins, Escherichia coli↗
PubMed1989

Reversal of dyskinesis by increased end diastolic segment length in ischaemic-reperfused myocardium.

Persistent dyskinesis is universally observed after reperfusion of a severely ischaemic segment. Although inotropic stimulation shows a latent contractile reserve, it is not known whether this reserve can be recruited by increasing end diastolic segment length (local length-tension relation). To investigate this, six anaesthetised open chest dogs were placed on right heart bypass to increase end diastolic segment length independently of mean arterial pressure. Instantaneous left ventricular pressure-segment length relations and fractional systolic shortening were determined by sonomicrometry in the centre of the region perfused by the left anterior descending coronary artery during sequential increases in end diastolic segment length. Measurements were made before occlusion of the left anterior descending coronary artery, during 1 h of occlusion, and after 2 h of reperfusion. Before ischaemia, segmental shortening increased from 11.0(SEM 1.6)% to 23.5(1.5)% (p less than 0.05) as end diastolic segment length increased. Dyskinesis developed during occlusion of the left anterior descending coronary artery [12.1(2.6)% control v -7.2(1.6)% occlusion, p less than 0.05] and was present over the entire range of end diastolic segment lengths. Following reperfusion, segmental dyskinesis [-2.5(2.4)%] persisted at the lower end of the range of end diastolic segment length, but was progressively replaced by active shortening, averaging 7.3(3.2)% (p less than 0.05) as end diastolic segment length was sequentially increased. We conclude that segmental function following reperfusion is sensitive to changes in end diastolic segment length, and that active shortening is recruited from an apparently dyskinetic segment as end diastolic segment length progressively increases.

Animals↗
PubMed1985

The basic phage set for typing bovine staphylococci.

Two hundred and sixty-nine Staphylococcus aureus cultures isolated from bovine milk were subjected to phage typing using the International basic set of 16 phages at Routine Test Dilution. In the current study 73.6% of cultures were 'typable' compared with 84-89% in 1972 when the set was first recommended. The set remains capable of typing the majority of bovine staphylococci but shows a reduction in lysogenicity of most of its phages.

Animals↗
PubMed1979

Diagnostic aspects of cerebrocortical necrosis.

Specimens from cattle and sheep suspected of having cerebrocortical necrosis (CCN) were studied. Rumenal contents were examined for thiaminase-producing bacteria. Thiaminase activity was assessed in rumenal contents. The thiamine concentration of liver, brain and heart was determined and erythrocyte transketolase assessed. Diagnosis in each case, whether positive or negative for CCN, was decided by histopathological examination. There was a substantial agreement between the biochemical findings and the histological diagnosis indicating that a provisional diagnosis may be made on clinical and biochemical data alone. The findings are discussed in relation to other diseases which have the same neuropathological features. Attempts to isolate thiaminase-producing bacteria, which may be implicated in the aetiology of CCN, were inconclusive.

Animals↗
PubMed1978

The social hour for geropsychiatric patients.

This study was an attempt to evaluate the effects of a controlled alcohol intake in the socialization of a group of geropsychiatric patients in a clinical setting. Although 47 patients of the Geriatric Unit were involved at various times, 16 remained in the study for the entire eight weeks. The Social Hour consisted of a half-hour session every weekday. The alcohol served was whisky, gin, vodka, and wine. Soft drinks were available for those who preferred them. Each patient was rated on a 5-point scale with regard to ward and off-ward activities. A planned four-week placebo period met with so much negativism that it had to be shortened to three days. According to our observations, the socialization process was increased significantly for these mentally ill geriatric patients during this type of Social Hour.

Aged↗
PubMed1977

Listener judgement of differences in stutterers' nonstuttered speech during chorus- and nonchorus-reading conditions.

The hypothesis that a stutterer's usual manner of speaking changes during chorus reading was tested. Nine stutterers orally read a passage under chorus- and nonchorus-reading conditions. Stutter-free speech samples of similar prose content were obtained from oral readings made between and within both conditions. Observers were asked to identify pairs of samples made under different (chorus/nonchorus) or similar (chorus/chorus or nonchorus/nonchorus) oral reading conditions. The results provided only partial support for the hypothesis. Observers were unable to distinguish confidently the speech sample group that was made under similar conditions from the sample group made under different conditions. However, judges were able to identify correctly samples from four of the nine stutterers that were made under different speaking conditions.

Adolescent↗
PubMed1975

Stress in hospitals. The married intern: vintage 1973.

Forty-five married interns and their spouses were interviewed about the stresses the intern's profession placed upon the marriage. Long hf hospitality to interns' wives in the hospital were seen as stresses which could be considerably eased by appropriate administrative action.

Australia↗