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M J Taylor

Publications and source records attributed to M J Taylor.

At least 19 recordsLinked to original sources
PubMed2006

Isospin symmetry of odd-odd mirror nuclei: identification of excited states in N=Z-2 48Mn.

Excited states have been observed in the N=Z-2 odd-odd nucleus 48Mn for the first time. Through comparison with the structure of 48V, a first high-spin study of an odd-odd mirror pair has been achieved. Differences between the T=1 analogue states in this pair have been interpreted in terms of Coulomb effects, with the aid of shell-model calculations in the full pf valence space. Unlike other mirror pairs, the energy differences have been interpreted almost entirely as due to a monopole effect associated with smooth changes in radius (or deformation) as a function of angular momentum. In addition, the large energy shift between analogue negative-parity states is interpreted in terms of the electromagnetic spin-orbit interaction in nuclei.

Journal Article↗
PubMed2006

A noisy transform predicts saccadic and manual reaction times to changes in contrast.

One of the most important factors affecting the time taken to respond to a visual stimulus is contrast, and studies of reaction time can provide precise, quantitative information about the underlying signal processing. In this study we measured both saccadic and manual reaction times to step increments in target contrast. Our results over a range of initial contrasts are consistent with a simple model consisting of a noisy logarithmic transducer followed by a rise-to-threshold accumulator. A systematic comparison with previous contrast-processing models also shows that the commonly used method of linear regression may not be a particularly sensitive tool in deciding between them. We found similar parameters for the contrast processor in both saccadic and manual reaction times, as might be expected if a common target detection stage precedes each type of reaction.

Adult↗
PubMed2005

Molecular analyses of mycobacteria other than the M. tuberculosis complex isolated from Northern Ireland cattle.

Mycobacteria other than the Mycobacterium tuberculosis complex (MOTT), isolated from Northern Ireland cattle, were identified by PCR amplification of the 16S rRNA gene, and subsequent reverse cross blot hybridisation and sequence analyses. Elucidation of the MOTT species was to facilitate specificity testing of new and existing diagnostic test reagents for bovine tuberculosis. The presence of the genes for potential diagnostic antigens: MPB70, MPB64, ESAT-6 and CFP-10 in the isolated MOTT species was investigated. Molecular analyses of cultured isolates from bovine lymph node specimens of 48 cattle identified a wide variety of mycobacterial species including Mycobacterium nonchromogenicum, Mycobacterium malmoense, Mycobacterium bohemicum, Mycobacterium paratuberculosis, Mycobacterium avium, Mycobacterium kansasii, Mycobacterium holsaticum, Mycobacterium palustre, Mycobacterium sp. IWGMT 90210, Mycobacterium sp. LIV-2129, a potentially novel mycobacterial species (EMBL/GenBank/DDBJ Accession Number AJ617495) and Rhodococcus equi. Apart from M. kansasii, the results of traditional (standard phenotypic and biochemical) and molecular identification methods did not correlate well, with traditional methods identifying fewer species. Most of the species identified were either recognised pathogenic or potential pathogenic species. The genes for ESAT-6, CFP-10 and, unusually, MPB64 were detected in M. kansasii only. The MPB70 gene was not detected in any of the species. This study supported restricted species distribution of these genes as well as identifying a different range of MOTT species that could be included in specificity testing of new diagnostic reagents for bovine tuberculosis.

Animals↗
PubMed2004

Determination of chloralose residues in animal tissues by liquid chromatography-electrospray ionisation tandem mass spectrometry.

A relatively rapid and specific method for the determination of chloralose in animal tissues by LCMSMS was developed. Isocratic reverse phase HPLC was used to introduce samples for electrospray negative ionisation tandem mass spectrometry. Methanol extracts were diluted to approximate the mobile phase composition, then filtered prior to analysis. Residues were identified by monitoring the multiple reaction monitoring (MRM) transitions of precursor ions mass:charge (m/z) 309 and 307 to a common m/z 161 product ion. Qualitative and quantitative confirmation data were acquired simultaneously by monitoring alternative MRM transitions. Calibration was linear over a working range of 0.025-1.3 microg/ml, and the limit of quantitation (LOQ) was 0.28 mg/kg for liver. The mean recovery was 88.5% from chicken muscle tissue fortified at 198-237 mg/kg, and ranged from 81.3 to 94.3% from liver tissue fortified at 1-52 mg/kg. The method is compared to a gas chromatography (GC) procedure previously employed.

Animals↗
PubMed2004

Inositol for depressive disorders.

BACKGROUND: There are a number of effective interventions for the treatment of depression. It is possible that the efficacy of these treatments will be improved further by the use of adjunctive therapies such as inositol. OBJECTIVES: 1. To determine the effectiveness of inositol in the treatment of depression.2. To determine the adverse effects and acceptability of treatment with inositol. SEARCH STRATEGY: The Cochrane Controlled Trials Register (CCTR), The Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Register (CCDANCTR) incorporating results of group searches of EMBASE, MEDLINE, LILACS, CINAHL, PSYNDEX and PsycLIT were searched. Reference lists of relevant papers and major textbooks of affective disorder were checked. Experts in the field and pharmaceutical companies were contacted regarding unpublished material. SELECTION CRITERIA: All randomised controlled trials that compare treatment with inositol, whether as monotherapy or adjunctive therapy, to an alternative treatment, whether another antidepressant medication or placebo, for patients with a diagnosis of depressive disorder (diagnosed according to explicit criteria). DATA COLLECTION AND ANALYSIS: Data were independently extracted from the original reports by two reviewers. Statistical analysis was conducted using Review Manager version 4.2.1. MAIN RESULTS: Four trials were identified, with a total of 141 participants. These were short term trials of double-blind design. The trials did not show clear evidence of a therapeutic benefit, nor any evidence of poor acceptability. REVIEWERS' CONCLUSIONS: It is currently unclear whether or not inositol is of benefit in the treatment of depression. Ongoing studies should reduce this uncertainty.

Antidepressive Agents↗
PubMed2004

PCR studies of feline leprosy cases.

16S rRNA gene sequence analysis provided evidence for two different mycobacterial species, Mycobacterium lepraemurium and a potentially novel species, as causative agents of 'feline leprosy'. Comparison of 16S rRNA gene sequence data obtained for M. lepraemurium and the potentially novel species indicated 12 nucleotide differences over a 446 bp region encompassing the V2 and V3 hypervariable regions. From available 16S rRNA gene sequence data, M. lepraemurium shared greatest nucleotide identity with M. avium subsp paratuberculosis and M. avium. The novel species had a long helix 18 in the V3 region and shared greatest nucleotide identity with M. leprae, M. haemophilum and M. malmoense. The novel species had an additional 'A' nucleotide at position 105 of the aligned 16S rRNA gene sequence, the only other mycobacterial database sequence having this same extra nucleotide being M. leprae. This nucleotide variation was exploited to develop specific PCR assays for the two species. These were found to be effective and specific when tested against a panel of mycobacteria including species found in feline leprosy lesions and closely related mycobacteria and also when applied directly to formalin-fixed, paraffin-embedded tissues from feline leprosy cases.

Animals↗
PubMed2004

The faces of development: a review of early face processing over childhood.

The understanding of the adult proficiency in recognizing and extracting information from faces is still limited despite the number of studies over the last decade. Our knowledge on the development of these capacities is even more restricted, as only a handful of such studies exist. Here we present a combined reanalysis of four ERP studies in children from 4 to 15 years of age and adults (n = 424, across the studies), which investigated face processing in implicit and explicit tasks. We restricted these analyses to what was common across studies: early ERP components and upright face processing across all four studies and the inversion effect, investigated in three of the studies. These data demonstrated that processing faces implicates very rapid neural activity, even in young children--at the P1 component--with protracted age-related change in both P1 and N170, that were sensitive to the different task demands. Inversion produced latency and amplitude effects on the P1 from the youngest group, but on N170 only starting in mid childhood. These developmental data suggest that there are functionally different sources of the P1 and N170, related to the processing of different aspects of faces.

Adolescent↗
PubMed2003

Efficacy trial of an irradiated cattle lungworm vaccine in red deer (Cervus elaphus).

Lungworm (Dictyocaulus sp.) is the parasite of most concern to the New Zealand deer industry. Although lungworm can be controlled by anthelmintics there is an increasing concern over excessive drenching programmes and reliance on chemicals for parasite control. A live irradiated larval vaccine developed for cattle has been available in Europe for the past 40 years but has never been evaluated in red deer in New Zealand. Four groups of red deer and two of cattle were hand reared from birth in parasite-free conditions. The cattle acted as a control group to ensure that the vaccine was still efficacious on arrival in New Zealand. Two groups of deer were vaccinated, and all four groups were challenged with either D. viviparus or deer origin Dictyocaulus, tentatively identified as D. eckerti. The vaccine provided excellent protection to cattle under New Zealand conditions, there was no larval output in the vaccinated cattle and no adults were found in their lungs at necropsy. In red deer, patency was delayed in the vaccinated groups regardless of challenge species and larval output was lower but was not prevented. Adult lungworms were found in the lungs of all deer at necropsy but fewer were recorded in the vaccinated deer. Although Huskvac provided a degree of protection for red deer it was not effective enough to recommend its use.

Animals↗
PubMed2003

Folate for depressive disorders.

BACKGROUND: There are a number of effective interventions for the treatment of depression. It is possible that the efficacy of these treatments will be improved further by the use of adjunctive therapies such as folate. OBJECTIVES: 1. To determine the effectiveness of folate in the treatment of depression 2. To determine the adverse effects and acceptability of treatment with folate. SEARCH STRATEGY: The Cochrane Controlled Trials Register (CCTR), and the Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Register (CCDANCTR) incorporating results of group searches of EMBASE, MEDLINE, LILACS, CINAHL, PSYNDEX and PsycLIT were searched. Reference lists of relevant papers and major textbooks of affective disorder were checked. Experts in the field and pharmaceutical companies were contacted regarding unpublished material. SELECTION CRITERIA: All randomised controlled trials that compared treatment with folic acid or 5'-methyltetrahydrofolic acid to an alternative treatment, whether another antidepressant medication or placebo, for patients with a diagnosis of depressive disorder (diagnosed according to explicit criteria). DATA COLLECTION AND ANALYSIS: Data were independently extracted from the original reports by two reviewers. Statistical analysis was conducted using Review Manager version 4.1. MAIN RESULTS: Three trials involving 247 people were included. Two studies involving 151 people assessed the use of folate in addition to other treatment, and found that adding folate reduced Hamilton Depression Rating Scale scores on average by a further 2.65 points (95% confidence interval 0.38 to 4.93). Fewer patients treated with folate experienced a reduction in their HDRS score of less than 50% at ten weeks (relative risk (RR) 0.47, 95% CI 0.24 to 0.92) The number needed to treat with folate for one additional person to experience a 50% reduction on this scale was 5 (95% confidence interval 4 to 33). One study involving 96 people assessed the use of folate instead of the antidepressant trazodone and did not find a significant benefit from the use of folate. The trials identified did not find evidence of any problems with the acceptability or safety of folate. REVIEWER'S CONCLUSIONS: The limited available evidence suggests folate may have a potential role as a supplement to other treatment for depression. It is currently unclear if this is the case both for people with normal folate levels, and for those with folate deficiency.

Antidepressive Agents↗
PubMed2003

Transmitted arterio-arterial anastomosis waveforms causing cyclically intermittent absent/reversed end-diastolic umbilical artery flow in monochorionic twins.

OBJECTIVES: To characterize the phenomenon of retrograde transmission of arterio-arterial anastomosis (AAA) interference patterns on umbilical artery (UA) waveform by (a) documenting the periodicity, (b) correlation with in vivo and in vitro demonstration of AAAs and (c) reproducing these patterns by computer modelling. METHODS: Monochorionic twins (MC) twins underwent placental and umbilical Doppler studies. AAAs were sought by pulse wave Doppler of their bi-directional interference pattern and confirmed by postnatal injection studies. The periodicity of transmitted patterns in the UA was determined. Determinants of the transmitted patterns were ascertained by computer modelling of physiological and fetal variables. RESULTS: Among 83 prospectively studied MC twin pregnancies; a transmitted pattern was observed in 6 (7 per cent) patients for 15-114 days. This was found in 20 per cent (6/30) of smaller MC twins discordant for growth restriction but in no appropriately grown twins. It was only observed in association with AAAs validated both in vivo and in ex vivo. Computer modelling demonstrated that this pattern could be reproduced by summating end diastolic flow with a high pulsatility index in the UA in the presence of a large AAA. Consistent with this, MC twins with a transmitted pattern had larger AAAs (median diameter 4.3 mm interquartile range 4.1-5.2) compared to MC twins discordant for intrauterine growth restriction (2.1 mm interquartile range 1.5 to 2.8) (P<0.05) without a transmitted pattern. Perinatal mortality was similar in the fetuses with and without transmitted patterns (0/12 vs. 2/48 P=0.7).

Adult↗
PubMed2003

Discrimination of single features and conjunctions by children.

Stimuli that are discriminated by a conjunction of features can show more rapid early processing in adults. To determine how this facilitation effect develops, the processing of visual features and their conjunction was examined in 7-12-year-old children. The children completed a series of tasks in which they made a target-non-target judgement as a function of shape only, colour only or shape and colour features, while event-related potentials were recorded. To assess early stages of feature processing the posteriorly distributed P1 and N1 were analysed. Attentional effects were seen for both components. P1 had a shorter latency and P1 and N1 had larger amplitudes to targets than non-targets. Task effects were driven by the conjunction task. P1 amplitude was largest, while N1 amplitude was smallest for the conjunction targets. In contrast to larger left-sided N1 in adults, N1 had a symmetrical distribution in the children. N1 latency was shortest for the conjunction targets in the 9-10-year olds and 11-12-year olds, demonstrating facilitation in children, but which continued to develop over the pre-teen years. These data underline the sensitivity of early stages of processing to both top-down modulations and the parallel binding of non-spatial features in young children. Furthermore, facilitation effects, increased speed of processing when features need to be conjoined, mature in mid-childhood, arguing against a hierarchical model of visual processing, and supporting a rapid, integrated facilitative model.

Aging↗
PubMed2003

Dictyocaulus species: cross infection between cattle and red deer.

AIM: To discover whether cross infection between red deer (Cervus elaphus) and cattle is possible with either a bovine isolate of the cattle lungworm, Dictyocaulus viviparus, or with a cervine isolate of the lungworm, Dictyocaulus eckerti which is thought to be maintained primarily in deer. METHOD: Twelve cattle and 12 red deer were reared parasite-free from birth. At 3-4 months of age, half of each species (n=6) were experimentally infected with D. viviparus and the other half with D. eckerti. The course of infection was monitored for 34 days, after which the animals were slaughtered and the lungs removed to assess levels of infection. RESULTS: Faecal larval counts demonstrated that patent Dictyocaulus infections occurred in all groups. At necropsy, adult worms were found in the lungs in all groups except the cattle that were infected with D. eckerti. The largest numbers of adult worms were found in the red deer infected with D. eckerti. CONCLUSION: It was demonstrated that both cattle and red deer could be infected with either D. viviparus or D. eckerti. However, D. eckerti larvae that originated from deer established more successfully in deer and D. viviparus larvae that originated from cattle established more successfully in cattle.

Journal Article↗
PubMed2003

Acute reboxetine administration increases plasma and salivary cortisol.

We investigated the effect of a single oral dose of the selective noradrenaline reuptake inhibitor, reboxetine (4 mg), on plasma and salivary cortisol in 24 healthy volunteers in a randomized, placebo-controlled, parallel-group design. Reboxetine significantly increased both plasma and salivary cortisol, although the correlation between the responses in plasma and saliva was modest. Our results are consistent with previous neuroendocrine challenge studies showing that potentiation of brain noradrenaline function stimulates the hypothalamic-pituitary-adrenal axis. Reboxetine-induced salivary cortisol release appears to be a simple and relatively non-invasive test of hypothalamic noradrenaline function. However, placebo-controlled, within-subject designs are likely to yield a more valid measure of noradrenaline-mediated cortisol release.

Administration, Oral↗
PubMed2002

Development of a sandwich ELISA and comparison with PCR for the detection of F11 and F165 fimbriated Escherichia coli isolates from septicaemic disease in farm animals.

The P fimbriae F11 and F165 that have been demonstrated on Escherichia coli septicaemic strains in poultry and calves, respectively, possess a nearly identical major subunit that demonstrates a serological cross-reaction. A polyclonal antibody-based sandwich ELISA (sELISA) that was specific for both F11 and F165 fimbriated strains was compared with a PCR method to detect F11/F165 fimbriated strains, in a collection of E. coli strains isolated from diseased animals. Of 298 isolates tested, 36 were positive by PCR of which only 14 were sELISA positive. There were no sELISA positive but PCR negative results. The 36 PCR positive isolates comprised 11 avian strains of which 10 were sELISA positive, 20 bovine strains of which 4 were sELISA positive and 3 ovine strains, 1 porcine strain and 1 equine strain all of which were sELISA negative. The F11/F165 incidence of 10.7% in 103 poultry and 18.3% in 109 bovine isolates demonstrates a moderate level of these factors in E. coli septicaemic cases in Northern Ireland.

Animals↗
PubMed2002

Visual categorization during childhood: an ERP study.

Categorization is a basic means of organizing the world around us and offers a simple way to process the mass of stimuli one perceives every day. The ability to categorize appears early in infancy, and has important ramifications for the acquisition of other cognitive capacities, but little is known of its development during childhood. We studied 48 children (7-15 years of age) and 14 adults using an animal/nonanimal visual categorization task while event-related potentials (ERPs) were recorded. Three components were measured: P1, N2, and P3. Behaviorally, the children performed the task very similarly to adults, although the children took longer to make categorization responses. Decreases in latencies (N2, P3) and amplitudes (P1, N2, P3) with age indicated that categorization processes continue to develop through childhood. P1 latency did not differ between the age groups. N2 latency, which is associated with stimulus categorization, reached adult levels at 9 years and P3 latency at 11 years of age. Age-related amplitude decreases started after the maturational changes in latencies were finished.

Adolescent↗
PubMed2002

A covalently stabilised glucose responsive gel formulation with a Carbopol carrier.

A novel glucose-responsive gel formulation was stabilised via covalent coupling to a carbomer resin. The gel formed between the plant lectin, concanavalin A and specific polysaccharides was stabilised to minimise leaching of gel components into the surroundings. This was required to prevent toxicity and to preserve the working mechanism of the formulation. Increased gel stability was introduced by covalently bonding amine groups present on the lysine residues of concanavalin A to carboxylic moieties on Carbopol 974P NF using carbodiimide chemistry. The introduction of dextran then produced a glucose-responsive formulation that transformed from gel to sol in the presence of free glucose. The rheological properties and in vitro component and insulin release of the carbomer-stabilised gel were evaluated. A decrease in viscosity over a chosen glucose concentration range was exhibited by the carbomer-based gel. The testing of such a formulation in in vitro diffusion experiments revealed that the leaching of concanavalin A from the covalently coupled gels was restricted significantly with respect to a non-coupled gel. Insulin delivery in response to glucose in the physiologically relevant glucose concentration range was demonstrated using the carbomer-stabilised gel at 37 degrees C. The performance of this novel self-regulating drug delivery system has been improved in terms of increased gel stability with reduced component leaching.

Acrylic Resins↗
PubMed2002

Covalent coupling of concanavalin A to a Carbopol 934P and 941P carrier in glucose-sensitive gels for delivery of insulin.

A novel glucose-sensitive gel formulation, containing concanavalin A and specific polysaccharides, was stabilised via covalent coupling to two structurally different carbomers. The bonding was done to minimise leaching of gel components thereby preventing toxicity and preserving the working mechanism of the gel. Increased gel stability was introduced by covalently bonding amine groups present on the lysine residues of concanavalin A to carboxylic moieties on Carbopol 934P NF and 941P NF using carbodiimide chemistry. The introduction of dextran then produced a glucose-sensitive formulation that transformed from gel to sol in the presence of free glucose. Rheological examination of glucose-sensitive gels stabilised in this way and containing varying concentrations of glucose was conducted with a cone and plate viscometer used in continual rotation mode. A decrease in viscosity over the chosen glucose concentration range was exhibited by both carbomer-stabilised formulations. The subsequent testing of such formulations in in-vitro diffusion experiments revealed that the leaching of concanavalin A from the covalently coupled gels is restricted significantly with respect to non-coupled formulations. In addition, insulin delivery in response to glucose in the physiologically relevant glucose concentration range has been demonstrated using the carbomer-stabilised gels at 37 degrees C. The performance of this self-regulating drug delivery system has been improved in terms of increased gel stability with reduced component leaching.

Acrylates↗