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S Lewis

Publications and source records attributed to S Lewis.

At least 19 recordsLinked to original sources
PubMed2007

IGF1, growth pathway polymorphisms and schizophrenia: a pooling study.

It has been hypothesized that insulin-like growth factors (IGFs) and components of the growth-hormone (GH)-IGF axis may underlie reported associations of poor fetal and childhood growth with schizophrenia. We have investigated the association of schizophrenia with 16 SNPs spanning the IGF1 gene with an inter-marker distance of approximately 2-3 kb. We also examined associations with four common functional polymorphisms of genes involved in aspects of the GH-IGF system--the IGF1 receptor (IGF1R), insulin receptor substrate (IRS1), growth hormone (GH1), and IGF binding protein-3 (IGFBP3). The study was based on an analysis of pooled DNA samples from 648 UK and Irish cases of schizophrenia and 712 blood donor controls and of 297 Bulgarian parent offspring trios. In replicated pool analyses, none of the 16 SNPs in IGF1 nor the 4 key SNPs in the other growth pathway genes were associated with schizophrenia. SNP coverage of IGF1 was extensive, so our findings do not support a major role for IGF-I in the aetiology of schizophrenia.

Bulgaria↗
PubMed2006

Staff-led interventions for improving oral hygiene in patients following stroke.

BACKGROUND: For people with limitations due to neurological conditions such as stroke, the routine practice of oral care may become a challenge. Evidence-based supported oral care intervention is essential for this patient group. OBJECTIVES: To compare the effectiveness of staff-led oral care interventions with standard care for ensuring oral hygiene for individuals after a stroke. SEARCH STRATEGY: We searched the trials registers of the Cochrane Stroke Group and Oral Health Group (August 2005), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 1, 2006), MEDLINE (1966 to February 2006), CINAHL (1982 to February 2006), Research Findings Electronic Register (February 2006), National Research Register (Issue 1, 2006), ISI Science and Technology Proceedings (August 2005), Dissertation Abstracts and Conference Papers Index (August 2005). We scanned reference lists from relevant papers and contacted authors and researchers in the field. SELECTION CRITERIA: We identified randomised controlled trials that evaluated one or more interventions designed to improve oral hygiene. Trials based on a mixed population were included, provided it was possible to extract the data specific to the individuals post stroke. DATA COLLECTION AND ANALYSIS: Two review authors independently classified identified trials according to the inclusion and exclusion criteria, assessed the trial quality and extracted data. Clarification was sought from study authors when required. MAIN RESULTS: Eight eligible randomised controlled trials were identified but only one provided stroke-specific information. It compared an oral health care education training programme (OHCE) delivered to nursing home care assistants to delayed training intervention in the control group. Comparisons were made at one and six months after the intervention, using the primary outcome measures dental plaque and denture plaque, and three secondary outcomes. The data available for the 67 individuals with a stroke (obtained from the larger cluster randomised controlled trial) showed that denture plaque scores were significantly reduced up to six months (p < 0.00001) after the intervention. Staff knowledge (P = 0.0008) and attitudes (P = 0.0001) towards oral care also improved significantly. AUTHORS' CONCLUSIONS: Based on one study with a small number of stroke survivors, providing oral care training for carers in a nursing home setting improves their knowledge of and attitudes towards the provision of oral care. In turn, residents' dentures were cleaner, though other oral hygiene measures did not change. Further evidence relating to oral care interventions is severely lacking, in particular with reference to care in hospital for those following stroke.

Caregivers↗
PubMed2006

Dynamics and internal stress at the nanoscale related to unique thermomechanical behavior in polymer nanocomposites.

A small amount of alumina nanoparticles in polymethylmethacrylate causes a sharp depression of the glass transition temperature (Tg) accompanied by a toughening of the composite. We investigated this phenomenon using multispeckle x-ray photon correlation spectroscopy. Measurements reveal a dynamic structure factor that has the form exp[-(t/taua)beta], with beta greater than 1. We show for the first time that beta(T) tracks the internal stress at the polymer-particle interface. The internal stress, which we propose arises due to the entropic penalty that the polymer faces in the presence of the nanoparticles, engenders temporally heterogeneous dynamics. In the jammed glassy state, we show that the dominant fast relaxation mode--taumax--aided by a weak dewetting interface relieves the stress and follows the variations in Tg.

Journal Article↗
PubMed2006

Thromboprophylaxis in major abdominal surgery for cancer.

AIMS: To review the epidemiology and pathogenesis of venous thromboembolism (VTE) in surgical cancer patients, in addition to the use of thromboprophylaxis in major abdominal surgery, such as low-molecular-weight heparin (LMWH) and fondaparinux. METHODS: Systematic review of the literature, focussing on risk factors for VTE, parenteral methods of thromboprophylaxis, approaches to prolonged prophylaxis, and effects on patient survival. FINDINGS: Patients with cancer undergoing abdominal surgery are at substantially higher risk for VTE than patients without cancer. Furthermore, prolonged thromboprophylaxis for up to 4 weeks is more effective than short-term administration in these high-risk patients. The concurrent use of graduated compression stockings has a synergistic effect on the reduction in VTE risk. CONCLUSIONS: Thromboprophylaxis with LMWH has been shown to minimise the incidence of thromboembolic events, and is a well-established therapy worldwide. The American College of Chest Physicians recommends the routine use of thromboprophylaxis, with LMWH or unfractionated heparin, in patients with cancer who are undergoing surgical procedures, and the appropriate use of these thromboprophylactic agents has significant implications for the clinical care and quality of life of surgical patients with cancer.

Abdomen↗
PubMed2006

Cannabis-induced psychosis-like experiences are associated with high schizotypy.

OBJECTIVE: Recent studies have suggested that cannabis use is a risk factor for developing schizophrenia. We tested the hypothesis that cannabis use increases the likelihood of psychosis-like experiences in non-clinical participants who scored highly on a measure of schizotypy. METHOD: The psychological effects of cannabis were assessed in 137 healthy individuals (76% female, mean age 22 years) using a newly developed questionnaire concerned with subjective experiences of the drug: the Cannabis Experiences Questionnaire. The questionnaire has three subscales: Pleasurable Experiences, Psychosis-Like Experiences and After-Effects. Respondents also completed the brief Schizotypal Personality Questionnaire. RESULTS: Cannabis use was reported by 72% of the sample. Use per se was not significantly related to schizotypy. However, high scoring schizotypes were more likely to report both psychosis-like experiences and unpleasant after-effects associated with cannabis use. The pleasurable effects of cannabis use were not related to schizotypy score. CONCLUSION: High scoring schizotypes who use cannabis are more likely to experience psychosis-like phenomena at the time of use, and unpleasant after-effects. Our results are consistent with the hypothesis that cannabis use is a risk factor for full psychosis in this group.

Adult↗
PubMed2006

FOOD: a multicentre randomised trial evaluating feeding policies in patients admitted to hospital with a recent stroke.

OBJECTIVES: To determine whether routine oral nutritional supplementation of a normal hospital diet improves outcome after stroke (Trial 1); whether early tube feeding improves the outcomes of dysphagic stroke patients (Trial 2); and if tube feeding via a percutaneous endoscopic gastrostomy (PEG) results in better outcomes than that via a nasogastric tube (NG) (Trial 3). DESIGN: The Feed Or Ordinary Diet (FOOD) trial was a family of three pragmatic, randomised controlled trials (RCTs). They shared facilities for randomisation, data collection, follow-up and coordination. Patients could be co-enrolled in more than one of these trials. SETTING: Patients were enrolled in 131 hospitals in 18 countries. PARTICIPANTS: A total of 5033 patients who had been admitted to hospital with a recent stroke were enrolled in the trials between November 1996 and July 2003. INTERVENTIONS: In Trial 1, patients who could swallow within the first 30 days of admission were allocated to normal hospital diet versus normal hospital diet plus oral nutritional supplements (equivalent to 360 ml of 1.5 kcal/ml, 20 g of protein per day) until hospital discharge. In Trial 2, dysphagic patients enrolled within 7 days of admission were allocated to early enteral tube feeding versus avoid any enteral tube feeding for at least 1 week. In Trial 3, dysphagic patients were allocated within 30 days of admission to receive enteral tube feeding via PEG versus NG. MAIN OUTCOME MEASURES: Survival and the modified Rankin scale (MRS), a measure of functional outcome (grade 0 indicating no symptoms and grade 5 indicating severe disability, requiring help day and night). The primary outcomes were measured 6 months after enrollment, blind to treatment allocation, by the patient or their proxy completing a postal or telephone questionnaire. RESULTS: In Trial 1, 4023 patients were enrolled by 125 hospitals in 15 countries. Only 314 (7.8%) patients were judged undernourished at baseline. Vital status and MRS at the end of the trial were known for 4012 (99.7%) and 4004 (99.5%), respectively. Of the 2007 allocated normal hospital diet, 253 (12.6%) died, 918 (45.7%) were alive with poor outcome (MRS 3-5) and 823 (41.1%) had a good outcome (MRS 0-2). Of the 2016 allocated oral supplements, 241 (12.0%) died, 953 (47.3%) were alive with poor outcome and 813 (40.4%) had a good outcome. The supplemented diet was associated with an absolute reduction in risk of death of 0.7% (95% CI -1.4 to 2.7; p = 0.5) and a 0.7% (95% CI -2.3 to 3.8, p = 0.6) increased risk of death or poor outcome. In Trial 2, a total of 859 patients were enrolled by 83 hospitals in 15 countries. MRS at the end of the trial was known for 858 (99.9%). At follow-up, of 429 allocated early tube feeding, 182 (42.4%) died, 157 (36.6%) were alive with poor outcome (MRS 4-5) and 90 (21.0%) had a good outcome (MRS 0-3). Of 430 allocated avoid tube feeding 207 (48.1%) died, 137 (31.9%) were alive with poor outcome and 85 (19.8%) had a good outcome. Early tube feeding was associated with an absolute reduction in risk of death of 5.8% (95% CI -0.8 to 12.5; p = 0.09) and a reduction in death or poor outcome of 1.2% (95% CI -4.2 to 6.6; p = 0.7). In Trial 3, 321 patients were enrolled by 47 hospitals in 11 countries. Of 162 allocated PEG, 79 (48.8%) died, 65 (40.1%) were alive with poor outcome and 18 (11.1%) had good outcome. Of 159 allocated NG, 76 (47.8%) died, 53 (33.3%) were alive with poor outcome and 30 (18.9%) had good outcome. PEG was associated with an increase in absolute risk of death of 1.0% (95% CI -10.0 to 11.9; p = 0.9) and an increased risk of death or poor outcome of 7.8% (95% CI 0.0 to 15.5; p = 0.05). CONCLUSIONS: The results of Trial 1 would be compatible with oral supplementation being associated with a 1-2% absolute benefit or harm, but do not support routine supplementation of hospital diet for unselected stroke patients who are predominantly well nourished on admission. In Trial 2, the data suggest that a policy of early tube feeding may substantially reduce the risk of dying after stroke and it is very unlikely that the alternative policy of avoiding early tube feeding would significantly improve survival. Improved survival may be at the expense of increasing the proportion surviving with poor outcome. These data might usefully inform the difficult discussions about whether or not to feed a patient with a severe stroke. In Trial 3, the data suggest that in the first 2-3 weeks after acute stroke, better functional outcomes result from feeding via NG tube than PEG tube, although there was no major difference in survival. These data do not support a policy of early initiation of PEG feeding in dysphagic stroke patients. Future research might be focused on making NG tube feeding safer and more effective, also studies need to confirm the increased risk of gastrointestinal haemorrhage associated with tube feeding and, if confirmed, establish whether any interventions might reduce this risk. Future work might also aim to establish why worse functional outcomes occurred in PEG-fed patients because patients with prolonged dysphagia or intolerance of an NG tube are inevitably fed via a PEG tube.

Aged↗
PubMed2006

Problems associated with shellfish farming.

Shellfish culture is a major sector of aquaculture production worldwide, and zoonoses and drug residues associated with shellfish farm practice are of concern to public health. This paper focuses on three of the most important shellfish species: molluscs, crabs and shrimp. Although many diseases can affect shellfish, they do not appear to be transmittable to humans. Rather, the main hazards are associated with the methods used to farm the different species. The risk to human health from shellfish most commonly relates to contamination by biotoxins produced by marine algae. Another well-recognised problem associated with shellfish culture is the contamination of shellfish with domestic sewage that contains human pathogenic bacteria and viruses, which causes diseases such as typhoid fever and hepatitis. In shrimp farming, the main potential food safety hazards are zoonoses, chemical contamination and veterinary drug residues. Untreated effluent from shrimp farms is a major concern to the environmental sector as it is known to promote plankton blooms if directly discharged into natural water sources.

Animals↗
PubMed2005

Bupropion and the risk of sudden death: a self-controlled case-series analysis using The Health Improvement Network.

BACKGROUND: Bupropion is an effective smoking cessation therapy but its use in the UK has been limited by concerns that it may increase the risk of sudden death. METHODS: Data for all patients prescribed bupropion within The Health Improvement Network (a computerised general practice database) were extracted and the self-controlled case-series method was used to estimate the relative incidence of death during the first 28 days of treatment. The incidence of seizures, a recognised adverse effect of bupropion, was also investigated during this period. RESULTS: A total of 9329 individuals had been prescribed bupropion (mean age 44 years, 48% male). The total person-time after the first prescription for bupropion was 17,586 years, and during this time 121 people died. Two people died within the first 28 days of treatment, which was less than expected in comparison with the remaining observation period by an incidence ratio of 0.50 (95% confidence interval (CI) 0.12 to 2.05). Twenty eight people were recorded as having a total of 45 seizures (23 before starting bupropion, two in the first 28 days of treatment, and 20 at a later point). The relative incidence of seizures during the first 28 days of treatment was 3.62 (95% CI 0.87 to 15.09), equivalent to one additional seizure per 6219 first time bupropion users. CONCLUSIONS: Bupropion use is probably associated with an increased risk of seizures, but no evidence was found to suggest that the drug is associated with an increased risk of sudden death.

Antidepressive Agents, Second-Generation↗
PubMed2005

Failure of dietary oligofructose to prevent antibiotic-associated diarrhoea.

BACKGROUND: Oligofructose is metabolized by bifidobacteria, increasing their numbers in the colon. High bifidobacteria concentrations are important in providing 'colonization resistance' against pathogenic bacteria. AIM: To reduce the incidence of antibiotic-associated diarrhoea in elderly patients. METHODS: Patients over the age of 65 taking broad-spectrum antibiotics received either oligofructose or placebo. A baseline stool sample was cultured for Clostridium difficile and tested for C. difficile toxin. A further stool sample was analysed for C. difficile if diarrhoea developed. RESULTS: No difference was seen in the baseline characteristics, incidence of diarrhoea, C. difficile infection or hospital stay between the two groups (n = 435). Oligofructose increased bifidobacterial concentrations (P < 0.001, 95% CI: 0.69-1.72). A total of 116 (27%) patients developed diarrhoea of which 49 (11%) were C. difficile-positive and were more likely to be taking a cephalosporin (P = 0.006), be female (P < 0.001), to have lost more weight (P < 0.001, 95% CI: 0.99-2.00) and stayed longer in hospital (P < 0.001, 95% CI: 0.10-1.40). Amoxicillin (amoxycillin) and clavulanic acid increased diarrhoea not caused by C. difficile (P = 0.006). CONCLUSION: Oligofructose does not protect elderly patients receiving broad-spectrum antibiotics from antibiotic-associated diarrhoea whether caused by C. difficile or not. Oligofructose was well-tolerated and increased faecal bifidobacterial concentrations.

Aged↗
PubMed2005

Peripartum presentation of an acute aortic dissection.

We report the case of an acute type A aortic dissection occurring in a 35-year-old parturient. The initial diagnosis was missed; a subsequent emergency Caesarean section 3 weeks after presentation was followed by the development of left ventricular failure and pulmonary oedema in the early postoperative period. Echocardiography confirmed the diagnosis of aortic dissection and the patient underwent a successful surgical repair.

Acute Disease↗
PubMed2005

Reactome: a knowledgebase of biological pathways.

Reactome, located at http://www.reactome.org is a curated, peer-reviewed resource of human biological processes. Given the genetic makeup of an organism, the complete set of possible reactions constitutes its reactome. The basic unit of the Reactome database is a reaction; reactions are then grouped into causal chains to form pathways. The Reactome data model allows us to represent many diverse processes in the human system, including the pathways of intermediary metabolism, regulatory pathways, and signal transduction, and high-level processes, such as the cell cycle. Reactome provides a qualitative framework, on which quantitative data can be superimposed. Tools have been developed to facilitate custom data entry and annotation by expert biologists, and to allow visualization and exploration of the finished dataset as an interactive process map. Although our primary curational domain is pathways from Homo sapiens, we regularly create electronic projections of human pathways onto other organisms via putative orthologs, thus making Reactome relevant to model organism research communities. The database is publicly available under open source terms, which allows both its content and its software infrastructure to be freely used and redistributed.

Animals↗
PubMed2005

Predictors of operative death after oesophagectomy for carcinoma.

BACKGROUND: Oesophagectomy for carcinoma provides a chance of cure but carries significant risk. This study defined risk factors for death after oesophageal resection for malignant disease. METHODS: Between 1990 and 2003, 773 oesophagectomies for oesophageal cancer were performed. Continuous variables were categorized into quartiles for analysis. Predictors of operative mortality were identified by univariate and multiple logistic regression analysis. RESULTS: The operative mortality rate was 4.8 per cent (37 of 773). In univariate analysis, advanced age, reduced forced expiratory volume in 1 s (FEV1), reduced forced vital capacity, presence of diabetes and tumour located in the upper third of the oesophagus were associated with a higher mortality rate. Multivariate analysis identified age (highest relative to lowest quartile, odds ratio (OR) 4.87 (95 per cent confidence interval (c.i.) 1.35 to 17.55); P = 0.009), tumour position (upper third relative to other locations, OR 4.23 (95 per cent c.i. 1.06 to 16.86); P = 0.041) and FEV1 (lowest relative to highest quartile, OR 4.72 (95 per cent c.i. 1.01 to 21.99); P = 0.018) as independent predictors of death. CONCLUSION: Advanced age, impaired preoperative respiratory function and a tumour high in the oesophagus are associated with a significantly increased risk of death after oesophagectomy for carcinoma.

Adult↗
PubMed2005

An unusual case of massive gastric distension with catastrophic sequelae.

We report a case of massive gastric distension presenting with abdominal pain, shock and lower limb ischaemia. At laparotomy, gastric distension was found to be secondary to gastric outflow obstruction compounded by gas formation from antacid ingestion. Both the aorta and inferior vena cava were directly compressed by the distended stomach. This mode of presentation and combined aetiologies remain unreported. Gastric decompression resulted in profound cardiovascular compromise, multiorgan failure and eventually death.

Abdominal Pain↗
PubMed2005

Proximity of the home to roads and the risk of wheeze in an Ethiopian population.

BACKGROUND: There is widespread public concern that exposure to road vehicle traffic pollution causes asthma, but epidemiological studies in developed countries have not generally confirmed a strong effect and may have underestimated the risk as a result of relatively high and widespread exposure to traffic in everyday life. AIMS: To investigate the effect of living close to a traffic bearing road on the risk of wheezing in Jimma, Ethiopia where road traffic is generally low and restricted to a limited network of roads. METHODS: Data have been previously collected on respiratory symptoms, allergic sensitisation, and numerous demographic and lifestyle factors in a systematic sample of inhabitants of Jimma town. In 2003 the homes of these people were retraced; the shortest distance to the nearest surfaced road, and traffic flows on these roads were measured. RESULTS: Distance measurements were collected for 7609 (80%) individuals. The overall prevalence of wheeze was similar in those living within 150 m of a road compared to those living further away (3.9% v 3.7%), but among the 3592 individuals living within 150 m, the risk of wheeze increased significantly in linear relation to proximity to the road (adjusted odds ratio = 1.17 per 30 m proximity, 95% CI 1.01 to 1.36). This relation was stronger, though not significantly so, for roads with above median traffic flows. CONCLUSION: These findings indicate that living in close proximity to road vehicle traffic is associated with an increased risk of wheeze, but that other environmental factors are also likely to be important.

Adolescent↗
PubMed2005

Public health measures to reduce smoking prevalence in the UK: how many lives could be saved?

OBJECTIVE: To estimate the number of deaths that could be prevented in the UK by implementing population strategies to reduce smoking prevalence. DESIGN: A prospective analysis of future mortality using recent national smoking prevalence data and relative risks of mortality in current smokers, ex-smokers, and never-smokers. POPULATION: Smokers in the UK. INTERVENTIONS: Population measures of proven effectiveness assumed to reduce smoking prevalence by 1 percentage point per year for 10 years, or alternatively by 13% over 19 years (1 percentage point per annum for seven years, 0.5 percentage point per annum for 12 years) as considered to be achievable in a recent report to the UK Chancellor of the Exchequer. MAIN OUTCOME MEASURE: Estimated deaths from smoking prevented in the 35-75 year age group. RESULTS: Reducing the prevalence of smoking by 1 percentage point each year for 10 years would prevent 69 049 deaths at ages between 35 and 74 years during that period. The model of reduction by 13% over 19 years would prevent 54 308 and 194 493 deaths in 10 and 19 years, respectively. Continued prevalence reductions at the current rate of 0.4 percentage points each year will prevent 23 192 deaths over 10 years. CONCLUSIONS: Full implementation of simple population measures to encourage smoking cessation could prevent substantial numbers of deaths in the UK.

Adult↗
PubMed2005

Use of nicotine replacement therapy and the risk of acute myocardial infarction, stroke, and death.

OBJECTIVE: To determine whether nicotine replacement therapy (NRT) is associated with an increased risk of acute myocardial infarction, acute stroke, or death. DESIGN: Self control case series analysis of data from The Health Improvement Network (THIN) to estimate the relative incidence of myocardial infarction and stroke in four 14 day periods before and after the first prescription for NRT. SETTING: THIN is a computerised general practice database. SUBJECTS: Patients contributing data to THIN. INTERVENTIONS: Observational study of NRT. MAIN OUTCOMES: Acute myocardial infarction, acute stroke, and death. RESULTS: 33,247 individuals had been prescribed NRT, of whom 861 had had a myocardial infarction and 506 a stroke. There was a progressive increase in the incidence of first myocardial infarction in the 56 days leading up to the first NRT prescription (overall incidence ratio 5.55, 95% confidence interval (CI) 4.42 to 6.98), but the incidence fell after this time and was not increased in the 56 days after starting NRT (incidence ratio 1.27, 95% CI 0.82 to 1.97). The results were similar for second myocardial infarction and stroke, and for subgroups of people with pre-existing angina and hypertension. There were 960 deaths in our cohort during a mean follow up period of 2.6 years after starting NRT, with no evidence of an increased mortality in the 56 days after the NRT prescription (incidence ratio 0.86, 95% CI 0.60 to 1.23). CONCLUSIONS: The use of NRT is not associated with any increase in the risk of myocardial infarction, stroke, or death.

Adult↗
PubMed2004

The Gene Ontology (GO) database and informatics resource.

The Gene Ontology (GO) project (http://www. geneontology.org/) provides structured, controlled vocabularies and classifications that cover several domains of molecular and cellular biology and are freely available for community use in the annotation of genes, gene products and sequences. Many model organism databases and genome annotation groups use the GO and contribute their annotation sets to the GO resource. The GO database integrates the vocabularies and contributed annotations and provides full access to this information in several formats. Members of the GO Consortium continually work collectively, involving outside experts as needed, to expand and update the GO vocabularies. The GO Web resource also provides access to extensive documentation about the GO project and links to applications that use GO data for functional analyses.

Animals↗