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Biomedical subjects

J Smith

Publications and source records attributed to J Smith.

At least 19 recordsLinked to original sources
PubMed2006

Developmental differences in the neural bases of the face inversion effect show progressive tuning of face-selective regions to the upright orientation.

Face inversion hinders face processing in adults, while not affecting children in the same way. This fMRI study examines the neural underpinnings of the behavioral face inversion effect (FIE) from childhood to adulthood, and how face-selective regions in the brain may change with development. Adults, children, and teens performed a facial expression decision on upright and inverted face stimuli. In the right hemisphere (RH) all age groups showed similar profiles of neural activation for upright faces, but important developmental differences occured for inverted faces. For inverted faces, adults, and to a lesser degree teens, exhibited decreased levels of activity in the face-selective, right lateral fusiform gyrus (LFG). However, children exhibited greater activation for inverted than for upright faces in the same region. We found similar, but less robust, developmental trends in the right superior temporal sulcus (STS) and medial fusiform gyrus (MFG). Furthermore, the present study identifies the right LFG as the primary neural correlate of the behavioral FIE, and therefore of face processing expertise, by showing a significant correlation between the behavioral FIE and the neural FIE only in this region. Finally, the present findings shed some light on at least one of the possible mechanisms underlying the development of face processing expertise, by suggesting a progressive tuning of face-selective regions in the right hemisphere to the upright orientation, that extends well into adolescence.

Adolescent↗
PubMed2006

Development and validation of a patient-centred Measure of Activity Limitation (MAL) in rheumatoid arthritis.

OBJECTIVE: This study sought to understand patients' experiences of activity limitation in rheumatoid arthritis (RA) to inform the development and preliminary validation of a new patient-centred assessment tool. METHODS: Interviews, focus groups and diaries provided insight into patients' experiences of change in activity limitation. These data informed item generation for the Measure of Activity Limitation (MAL) questionnaire. Postal surveys, comprising the MAL, Short Form 36 (SF36) and Health Assessment Questionnaire (HAQ), were used to inform item reduction and assess the MAL's validity, reliability and sensitivity. RESULTS: Qualitative exploration of activity limitation with 30 patients led to the development of a 36-item questionnaire addressing the impact of symptoms on activity, difficulty in global function and difficulty in task performance. Analysis of data from a postal survey of 168 patients led to the development of a 19-item questionnaire which demonstrated moderate correlations with the HAQ and relevant scales of the SF36. A second postal questionnaire, completed on two occasions by 308 patients, assessed test-retest reliability. One hundred and ninety-three people reporting no change in disease showed mean change in MAL score between the two completions of 0.41 [95% confidence interval (CI) -0.38 -1.22)], demonstrating test-retest reliability. Thirty-two patients reporting improvement showed a mean change of -7.84 (95% CI -11.15 to -4.54) and 83 reporting deterioration showed mean change of 4.63 (95% CI 3.09-6.16), suggesting that the MAL is sensitive to self-reported clinical change. CONCLUSION: Our results suggest that the MAL is valid, reliable and sensitive to self-reported change. The MAL may provide a useful patient-centred adjunct to existing measures of activity limitation.

Adult↗
PubMed2006

Ensembl 2007.

The Ensembl (http://www.ensembl.org/) project provides a comprehensive and integrated source of annotation of chordate genome sequences. Over the past year the number of genomes available from Ensembl has increased from 15 to 33, with the addition of sites for the mammalian genomes of elephant, rabbit, armadillo, tenrec, platypus, pig, cat, bush baby, common shrew, microbat and european hedgehog; the fish genomes of stickleback and medaka and the second example of the genomes of the sea squirt (Ciona savignyi) and the mosquito (Aedes aegypti). Some of the major features added during the year include the first complete gene sets for genomes with low-sequence coverage, the introduction of new strain variation data and the introduction of new orthology/paralog annotations based on gene trees.

Animals↗
PubMed2006

MvirDB--a microbial database of protein toxins, virulence factors and antibiotic resistance genes for bio-defence applications.

Knowledge of toxins, virulence factors and antibiotic resistance genes is essential for bio-defense applications aimed at identifying 'functional' signatures for characterizing emerging or engineered pathogens. Whereas genetic signatures identify a pathogen, functional signatures identify what a pathogen is capable of. To facilitate rapid identification of sequences and characterization of genes for signature discovery, we have collected all publicly available (as of this writing), organized sequences representing known toxins, virulence factors, and antibiotic resistance genes in one convenient database, which we believe will be of use to the bio-defense research community. MvirDB integrates DNA and protein sequence information from Tox-Prot, SCORPION, the PRINTS virulence factors, VFDB, TVFac, Islander, ARGO and a subset of VIDA. Entries in MvirDB are hyperlinked back to their original sources. A blast tool allows the user to blast against all DNA or protein sequences in MvirDB, and a browser tool allows the user to search the database to retrieve virulence factor descriptions, sequences, and classifications, and to download sequences of interest. MvirDB has an automated weekly update mechanism. Each protein sequence in MvirDB is annotated using our fully automated protein annotation system and is linked to that system's browser tool. MvirDB can be accessed at http://mvirdb.llnl.gov/.

Bacterial Proteins↗
PubMed2006

Will Rogers revisited: prospective observational study of survival of 3592 patients with colorectal cancer according to number of nodes examined by pathologists.

To investigate the relationship between survival in colorectal cancer patients and the number of lymph nodes examined by a pathologist, previously attributed to stage migration, we used data from a cohort of 5174 colorectal cancer patients recruited between September 1991 and August 1994, and followed-up for 5 years. We selected cases with data present on all prognostic variables, and stratified them into three groups by number of nodes examined. We made a multivariate survival comparison using a Cox regression model. In all, there were 3592 cases with data present on all prognostic variables. Patients who had >10 nodes identified had a significant survival advantage over those who had 5-10 identified, who had in turn a similar advantage over those with 0-4 identified (P<0.001). This effect was present in the whole group and at all Dukes' stages, although statistically significant only in stages B (P=0.004) and C (P=0.019). The effect remained after adjustment in a Cox regression model in which the mean number of nodes taken out by each surgical firm did not predict survival. In a sub-group with data on lymphocytic infiltration into the primary tumour a survival advantage was noted in those with prominent rather than mild infiltration (P<0.001): the former also tended to have more nodes found (P=0.015). Stage migration alone cannot explain these results, as survival advantages are noted across the whole population independent of stage. Lymphocytic infiltration into the primary tumour is prognostically important, and is associated with the number of nodes found. Reactive enlargement of lymph nodes in the mesentery may make them easier to find, reflect immune response to the tumour, and thus indirectly impact upon survival.

Adenocarcinoma↗
PubMed2006

Comparison of experimental and simulated Kalpha yield for 400 nm ultrashort pulse laser irradiation.

Ti Kalpha emission yields from foils irradiated with approximately 45 fs, p-polarized pulses of a frequency-doubled Ti:sapphire laser are presented. A simple model invoking vacuum heating to predict absorption and hot electron temperature was coupled with the cross section for K -shell ionization of Ti and the Bethe-Bloch stopping power equation for electrons. The peak predicted Kalpha emission was in generally good agreement with experiment. This contrasts strongly with previous work at the fundamental frequency. Similar predictions using particle-in-cell (PIC) code simulation to estimate the number and temperature of hot electrons also gave good agreement for yield.

Journal Article↗
PubMed2006

Disease and psychological status in ankylosing spondylitis.

OBJECTIVES: Psychological factors may be important in the assessment and management of ankylosing spondylitis (AS). Our primary objective was to describe associations between disease and psychological status in AS, using AS-specific assessment tools and questionnaires. Our secondary objectives were to identify patient subgroups based on such associations and to determine the stability of the measures over time. METHODS: A total of 110 patients were assessed at 6-monthly intervals up to four times using tools to measure disease [Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Functional Index (BASFI) and the Bath Ankylosing Spondylitis Metrology Index (BASMI)], psychological [Hospital Anxiety and Depression Questionnaire (HADS), Health Locus of Control-Form C Questionnaire (HLC-C)] and generic health [Short form (SF)-36] status. RESULTS: Eighty-nine participants completed all four assessments. Throughout the study, BASDAI, BASFI and BASMI scores correlated significantly with anxiety, depression, internality and health status, but not with levels of belief in chance or powerful others. Clinically anxious or depressed subgroups had significantly worse BASDAI and BASFI, but not BASMI, scores. BASMI scores were the least closely linked to psychological status. Mean scores for disease, psychological and health status were clinically stable over the 18 months period. CONCLUSIONS: Disease status scores in AS correlated significantly with anxiety, depression, internality and health status. Interpretation of AS disease scores should take an account of psychological status and the choice of measures used. These findings have important potential applications in AS management and monitoring, including the identification of patients for biological therapies.

Adolescent↗
PubMed2006

Ensembl 2006.

The Ensembl (http://www.ensembl.org/) project provides a comprehensive and integrated source of annotation of large genome sequences. Over the last year the number of genomes available from the Ensembl site has increased from 4 to 19, with the addition of the mammalian genomes of Rhesus macaque and Opossum, the chordate genome of Ciona intestinalis and the import and integration of the yeast genome. The year has also seen extensive improvements to both data analysis and presentation, with the introduction of a redesigned website, the addition of RNA gene and regulatory annotation and substantial improvements to the integration of human genome variation data.

Animals↗
PubMed2006

IFN gamma and CXCR-1 gene polymorphisms in idiopathic bronchiectasis.

Idiopathic bronchiectasis is a disease of chronic, bacterial lung infection, unresolving inflammation and progressive lung damage. Bronchiectasis can be associated with autoimmune diseases including ulcerative colitis. Defects of both innate and adaptive immunity have been proposed. The airway inflammation is characterized by interleukin-8 (IL-8) expression and infiltration by neutrophils and T cells. Here we investigated two candidate gene polymorphisms that may contribute to disease susceptibility: a CXCR-1 (+2607 G/C) gene polymorphism that is implicated in IL-8 binding and neutrophil trafficking as well as the interferon-gamma (IFNgamma) (+874 T/A) polymorphism which is linked to levels of IFNgamma production. These polymorphisms were distributed similarly in the idiopathic bronchiectasis group and controls, suggesting that these two candidate gene polymorphisms are not associated with disease susceptibility.

Alleles↗
PubMed2006

Vocal tract resonances and the sound of the Australian didjeridu (yidaki) II. Theory.

The didjeridu (didgeridoo) or yidaki of the Australian Aboriginal people consists of the narrow trunk of a small Eucalypt tree that has been hollowed out by the action of termites, cut to a length of about 1.5 m, smoothed, and decorated. It is lip-blown like a trumpet and produces a simple drone in the frequency range 55 to 80 Hz. Interest arises from the fact that a skilled player can make a very wide variety of sounds with formants rather like those of human vowels, and can also produce additional complex sounds by adding vocalization. An outline is given of the way in which the whole system can be analyzed using the harmonic-balance technique, but a simpler approach with lip motion assumed shows easily that upper harmonics of the drone with frequencies lying close to impedance maxima of the vocal tract are suppressed, so that formant bands appear near impedance minima of the vocal tract. This agrees with experimental findings. Simultaneous vibration of the player's lips and vocal folds is shown to generate multiple sum and difference tones, and can be used to produce subharmonics of the drone. A brief discussion is given of player preference of particular bore profiles.

Acoustics↗
PubMed2006

Voriconazole therapeutic drug monitoring.

We report on 28 patients who underwent voriconazole monitoring because of disease progression or toxicity. A relationship (P<0.025) between disease progression and drug concentration was detected. Favorable responses were observed in 10/10 patients with concentrations above 2.05 microg/ml, while disease progressed in 44% (n=18) of patients with concentrations below 2.05 microg/ml.

Adult↗
PubMed2006

Predictors of ambulance use in patients with acute myocardial infarction in Australia.

AIMS: To determine ambulance transport rates and investigate predictors for ambulance use by patients with acute myocardial infarction (AMI) in Australia. METHODS: A prospective, cross-sectional descriptive survey using structured interviews. It included patients who were admitted to two hospitals (Western, Bendigo, Melbourne, Victoria, Australia) with AMI between 1 October 2004 and 31 March 2005, and data were collected by semistructured interview and medical record review. Data were analysed by descriptive statistics, univariate and multivariate analysis using SPSS. RESULTS: 105 patients were interviewed. 48 (46%) participants called for an ambulance as their initial medical contact. Participants who called for an ambulance had a shorter interval between symptom onset and presentation to hospital than those who did not (non-ambulance participants)(median 2.1 v 7.8 h; p = 0.001). Predictors of ambulance transport were older age (p = 0.008), symptom onset on the weekend (p = 0.022), presence of sharp chest pain (p = 0.011), self-administered anginine (p = 0.007), symptom onset at home (p = 0.027) and having a lower income (<dollarsA20 000; p = 0.022). After multivariate analysis, self-administered anginine, sharp chest pain and occurrence of symptom onset at home remained as independent predictors of ambulance use. CONCLUSION: A substantial number of patients do not call for an ambulance as their first medical contact after the onset of AMI symptoms. Public education on the benefits of ambulance transport and early treatment, as well as recognition of AMI symptoms, is required.

Adult↗