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S Platt

Publications and source records attributed to S Platt.

At least 19 recordsLinked to original sources
PubMed2006

Telomerase reverse transcriptase (TERT) expression and proliferation in canine brain tumours.

Telomerase is a ribonucleoprotein enzyme complex that synthesizes telomere DNA. It is detected in 85-90% of malignant tumours in humans, but not in most somatic cells. Because telomerase plays a critical role in cell immortality, it represents an important target for anticancer therapies. We have previously shown that the dog is a potentially useful model for evaluating telomerase-based therapeutics. In this present study we analysed 93 canine brain tumours for telomerase reverse transcriptase (TERT) expression by immunohistochemistry. TERT immunoreactivity was detected in 16 of 50 grade 1 (32%) and 29 of 43 grade 2 tumours (67.4%), demonstrating a statistically significant association with histological grade (P = 0.00012). A subset of 51 tumours was also assessed for MIB-1 expression. The MIB-1 labelling index (LI) was found to correlate significantly with tumour grade, with a mean MIB-1 LI of 1.5% for grade 1 tumours, as compared with a mean MIB-1 LI of 21.7% for grade 2 tumours (P << 0.001). The MIB-1 LI was also significantly associated with TERT expression in all brain tumours (P << 0.001). These data further support the dog as a model for the preclinical development of telomerase-based therapeutics in brain tumours.

Animals↗
PubMed2006

A bioinformatics pipeline for high-throughput microbial multilocus sequence typing (MLST) analyses.

Multilocus sequence typing (MLST) analysis for semi-routine applications is hindered by the downstream, manually intensive steps of processing the raw sequence data files. This report describes the development of an MLST pipeline that automates DNA sequence editing and analysis in order to significantly reduce the time required for processing data. Validation using a pneumococcal dataset revealed complete agreement between the results generated by manual and automated workflows. The MLST pipeline was developed for both double-strand and single-strand sequencing.

Bacteria↗
PubMed2005

Assessing psychological well-being: a holistic investigation of NHS employees.

A substantial body of research has investigated the effects of work on the psychological well-being of employees. However, there has been little assessment of the ways in which workplace factors (such as job demands, working conditions, inter-personal relations and workplace change) interact with personal factors (such as work-life balance, family circumstances, key personality traits or demographic characteristics) to affect psychological health. This article reports findings from a study which aimed to construct and test a comprehensive model of the influences on employee well-being within the UK National Health Service (NHS). The results show that psychological well-being is influenced by a complex array of personal, environmental and work factors. A key finding is that there are clear associations between workplace change and well-being and between work-life (im)balance and well-being. These effects appear to be independent of one another and therefore require separate attention from managers and employers.

Data Collection↗
PubMed2005

Trends in smoking behaviour between 1985 and 2000 in nine European countries by education.

OBJECTIVE: To examine whether trends in smoking behaviour in Western Europe between 1985 and 2000 differed by education group. DESIGN: Data of smoking behaviour and education level were obtained from national cross sectional surveys conducted between 1985 and 2000 (a period characterised by intense tobacco control policies) and analysed for countries combined and each country separately. Annual trends in smoking prevalence and the quantity of cigarettes consumed by smokers were summarised for each education level. Education inequalities in smoking were examined at four time points. SETTING: Data were obtained from nine European countries: Norway, Sweden, Denmark, Finland, the United Kingdom, the Netherlands, Germany, Italy, and Spain. PARTICIPANTS: 451 386 non-institutionalised men and women 25-79 years old. MAIN OUTCOME MEASURES: Smoking status, daily quantity of cigarettes consumed by smokers. RESULTS: Combined country analyses showed greater declines in smoking and tobacco consumption among tertiary educated men and women compared with their less educated counterparts. In country specific analyses, elementary educated British men and women, and elementary educated Italian men showed greater declines in smoking than their more educated counterparts. Among Swedish, Finnish, Danish, German, Italian, and Spanish women, greater declines were seen among more educated groups. CONCLUSIONS: Widening education inequalities in smoking related diseases may be seen in several European countries in the future. More insight into effective strategies specifically targeting the smoking behaviour of low educated groups may be gained from examining the tobacco control policies of the UK and Italy over this period.

Adult↗
PubMed2003

Prevalence of legionella waterline contamination and Legionella pneumophila antibodies in general dental practitioners in London and rural Northern Ireland.

OBJECTIVES: To determine the prevalence of legionellae in dental unit waterlines (DUWL) in general dental practices in London and rural Northern Ireland and whether the organism occurs at a high enough frequency and magnitude in DUWL to represent a threat to dentists' health. MATERIALS AND METHOD: Two hundred and sixty six (166 London, 100 Northern Ireland) randomly selected dental surgeries were recruited. Standardised 250 ml water samples were taken from the DUWL and 1 litre samples from the surgery cold water tap to measure the prevalence of legionellae. The dentists provided a blood sample for legionella serology. RESULTS: The prevalence of legionellae was very low (0.37%). Legionellae were not isolated from DUWL or surgery basin taps in Northern Ireland. Legionella spp were isolated from the DUWL and surgery basin of one practice in London and from the cold water supply of a further three practices. The prevalence of Legionella pneumophila antibodies was less than that seen in a comparable group of London blood donors. CONCLUSION: The risk to dentists' health from potential exposure to legionellae in this cohort of dentists was very low and this was confirmed by the very low seroprevalence and antibody titres to legionella detected in the dentists.

Antibodies, Bacterial↗
PubMed2003

Cell therapy using encapsulated cells producing endostatin.

Despite aggressive surgery and post-operative radiation and chemotherapy, the prognosis is poor for glioblastoma patients. Anti-angiogenic therapy with compounds such as endostatin could delay the onset of relapse. However, the short systemic half-life of this proteins as well as the blood-brain barrier makes the use of this therapy difficult for brain cancer patients. The aim of this project is to develop and implant genetically engineered producer cells secreting endostatin that are encapsulated in calcium cross-linked alginate gel beads. Encapsulation of cells within alginate gels has a potential as a sustained release system in addition to the fact that the encapsulation technology protects the cells from rejection by the immune system. Human embryonal kidney 293 cells have been transfected with the gene for endostatin. These cells have been encapsulated in calcium cross-linked alginate gels and optimized for the secretion of endostatin. Alginate gel beads implanted into rat brain have shown only a moderate loss in cell viability but extended endostatin release for periods of up to 12 months. Visualization of the anti-angiogenic effect on C6 rat glioma growth, tumor vasculature and microhemodynamics has been demonstrated by using intravital video microscopy. The data indicates that endostatin greatly affects tumor-associated microcirculation but does not appear to affect normal microcirculation. The local delivery of endostatin seems to specifically affect tumor-associated microvessels by reduction of the vessel density, diameter and functionality. Tumor cell migration and invasion was greatly reduced in the endostatin treated animals.

Alginates↗
PubMed2002

Community interventions for reducing smoking among adults.

BACKGROUND: Since smoking behaviour is determined by social context, the best way to reduce the prevalence of smoking may be to use community-wide programmes which use multiple channels to provide reinforcement, support and norms for not smoking. OBJECTIVES: To assess the effectiveness of community interventions for reducing the prevalence of smoking. SEARCH STRATEGY: We searched the Cochrane Tobacco Addiction Group specialised register, MEDLINE (1966-August 2001) and EMBASE (1980-August 2001) and reference lists of articles. SELECTION CRITERIA: Controlled trials of community interventions for reducing smoking prevalence in adult smokers. The primary outcome was smoking behaviour. DATA COLLECTION AND ANALYSIS: Data were extracted by one person and checked by a second. MAIN RESULTS: Thirty two studies were included, of which seventeen included only one intervention and one comparison community. Only four studies used random assignment of communities to either the intervention or comparison group. The population size of the communities ranged from a few thousand to over 100,000 people. Change in smoking prevalence was measured using cross-sectional follow-up data in 27 studies. The estimated net decline ranged from -1.0% to 3.0% for men and women combined (10 studies). For women, the decline ranged from -0.2% to + 3.5% per year (n=11), and for men the decline ranged from -0.4% to +1.6% per year (n=12). Cigarette consumption and quit rates were only reported in a small number of studies. The two most rigorous studies showed limited evidence of an effect on prevalence. In the US COMMIT study there was no differential decline in prevalence between intervention and control communities, and there was no significant difference in the quit rates of heavier smokers who were the target intervention group. In the Australian CART study there was a significantly greater quit rate for men but not women. REVIEWER'S CONCLUSIONS: The failure of the largest and best conducted studies to detect an effect on prevalence of smoking is disappointing. A community approach will remain an important part of health promotion activities, but designers of future programmes will need to take account of this limited effect in determining the scale of projects and the resources devoted to them.

Community Participation↗
PubMed2001

Principles in practice: reflections on a 'postpositivist' approach to evaluation research.

User participation is currently seen as an ethically appropriate way to proceed when researching disadvantaged groups and it is encouraged by funding agencies. However, the literature rarely discusses the methodological and practical implications for researchers attempting to incorporate user participation into evaluation studies which are informed from an epistemologically opposed (positivist) research paradigm. The paper explores this issue by drawing on the evaluation of a community-based smoking intervention to describe and reflect upon the recruitment, training and employment of local residents as survey interviewers. While the evaluation methodology adopts a quasi-experimental approach, the appointment of local residents as survey interviewers reflects an alternative (interpretive) research tradition. The combined strategy constitutes a postpositivist methodology in that it combines a data collection strategy more akin to interpretive social science while retaining a positivistic epistemological framework. The paper describes some logistics of this approach and problems encountered during the course of survey. While many of the problems described may be routinely associated (although seldom aired) with survey work, particularly in disadvantaged areas, the paper suggests they are also a function of the postpositivist research strategy which we adopted. The failure to involve interviewers in the conception and development of the evaluation meant that they lacked identification with our endeavour and this had practical implications for the survey interviewing. Although the survey was successfully executed and the employment of local residents was a valuable and worthwhile experience, the authors recognize that this narrow conception of user involvement meant that many of the potential benefits (both to the research and the participants) associated with participatory approaches were forfeited.

Community Participation↗
PubMed2000

Smokers at risk: implications of an institutionally bordered risk-reduced environment.

The paper draws on an evaluation of a workplace smoking policy implemented at Edinburgh University to examine some implications for smokers at work. While the objective of institutional risk-reduced environments is to diminish or control the level of risk behaviour within, they may have unanticipated implications for participants who are unwilling or unable to adapt. Data presented in the paper suggest that the University smoking policy carried its own risk. That is, the policy did not impact equally upon all members of the organisation but was experienced as divisive in contributing towards and sustaining social inequalities among staff.

Attitude to Health↗
PubMed1998

The psychological autopsy approach to studying suicide: a review of methodological issues.

The psychological autopsy approach to studying suicide is becoming an increasingly used research method. It presents considerable methodological problems. In order to assist future researchers in this field and to help readers assess reports of psychological autopsy studies the authors have reviewed these issues on the basis of their own experience and those of other workers. The areas covered include research design, identification of subjects, sources of information and the particular issues concerned with approaching relatives and other informants, choice and recruitment of controls, the difficulties of conducting psychological autopsy interviews with relatives, problems for interviewers, the selection of appropriate measures to obtain information, and achieving valid and reasonably reliable conclusions from diverse information sources.

Autopsy↗
PubMed1997

Predischarge arrhythmia induction testing of implantable defibrillators may be unnecessary in selected cases.

Complete postoperative evaluation of implantable cardioverter-defibrillators (ICDs) before discharge, including arrhythmia induction, has been the standard since their introduction. Whereas the original ICDs provided little telemetered information and used separate pace-sense and defibrillation leads, modern, third-generation devices provide pace-sense function information in addition to other data and are used in conjunction with integrated transvenous endocardial leads that combine pace-sense and defibrillation function. Changes in lead position, which can potentially result in either an inability to detect fibrillation or to terminate it, should be mirrored by changes in resting pace-sense function. Thus, for newer ICDs implanted with integrated endocardial lead systems, it is possible that in at least some cases predischarge arrhythmia inductions can be avoided. Two hundred patients receiving third-generation ICDs in conjunction with integrated transvenous leads were evaluated before discharge. Defibrillation detection or termination problems were seen in 8. Declines in resting R-wave amplitude and pacing impedance were significantly associated with such complications (-7 +/- 5 vs -0.3 +/- 2.3 mV [p <0.0001] and -158 +/- 138 vs -93 +/- 76 omega [p <0.05], for those with vs without complications, respectively), as were gross right ventricular lead migrations on chest x-ray. No patient with a defibrillation complication had an R-wave change of <3 mV. However, 13% of patients without complications had R-wave changes of >3 mV. It is concluded that a pace-sense evaluation of ICDs may be a satisfactory screen to determine those who need to go on to complete testing with arrhythmia induction in selected cases.

Aged↗
PubMed1997

Effectiveness of antismoking telephone helpline: follow up survey.

OBJECTIVE: To evaluate the effectiveness of an antismoking campaign conducted by the Health Education Board for Scotland. DESIGN: Descriptive survey of adult callers to a telephone helpline (Smokeline) for stopping smoking; panel study of a random sample of adult callers; assessment of changes in prevalence of smoking in Scotland before and after introduction of the helpline. SETTING: Telephone helpline. SUBJECTS: Callers to Smokeline over the initial one year period. Detailed information was collected on a 10% sample (n = 8547). A cohort of adult smokers who called Smokeline (total n = 848) was followed up by telephone interview three weeks, six months, and one year after the initial call. MAIN OUTCOME MEASURES: Numbers of adult smokers calling helpline; changes in smoking behaviour, especially stopping smoking among cohort members; and changes in prevalence of smoking in the general population. RESULTS: An estimated 82782 regular adult smokers made genuine contact with Smokeline over the year, representing about 5.9% of all adult smokers in Scotland. At one year 143 of the cohort of 848 callers (23.6%; 95% confidence interval 20.2% to 27.0%) reported that they had stopped smoking and 534 (88.0%; 85.4% to 90.6%) reported having made some change. About 19500 (16700 to 22350) adult smokers, equivalent to 1.4% (1.2% to 1.6%) of the mean adult smoking population, stopped smoking with direct help from Smokeling. During the second year of the campaign (1994) smoking prevalence among 25-65 year olds in Scotland was 6% (2.0% to 10.0%) lower than it had been before the start of the campaign. CONCLUSION: The Health Education Board for Scotland's antismoking campaign reached a high number of adult smokers, was associated with a highly acceptable quit rate among adults given direct help through Smokeline, and contributed considerably to an accelerated decline in smoking prevalence in Scotland.

Adolescent↗