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J Wilson

Publications and source records attributed to J Wilson.

At least 55 records · Page 3Linked to original sources
PubMed2004

The use of modelling to evaluate new drugs for patients with a chronic condition: the case of antibodies against tumour necrosis factor in rheumatoid arthritis.

OBJECTIVES: To address the structural issues relating to mortality and quality of life (QoL) effects and to identify data on the general pattern of QoL of rheumatoid arthritis (RA) patients through a restructured and enhanced version of the Birmingham Preliminary Model (BPM). DATA SOURCES: Electronic databases and a postal survey of current UK rheumatological practice. REVIEW METHODS: The focus for this report was to evaluate two new drugs, etanercept and infliximab [antibodies against tumour necrosis factor (anti-TNFs)], for use in the treatment of RA using the Birmingham Rheumatoid Arthritis Model (BRAM). Having carried out a rapid systematic review of physician surveys of current disease-modifying antirheumatic drugs (DMARDs) usage patterns in adult patients with RA and a postal survey of consultant rheumatologists working in the UK, the drug sequences were then identified for the model. A series of analyses were then run using the model. The issue of specifying the correct comparison in the analysis being undertaken was investigated using two separate analyses: the situation of comparing anti-TNFs with placebo, and the comparison of a sequence using anti-TNFs with a sequence that represents current practice in the UK. RESULTS: Results from the survey of rheumatologists highlighted the fact that RA has different manifestations and responds to different agents in different patients, all of which makes any summary of practice difficult to achieve and open to the criticism of being an oversimplification. However, the findings generally agree with other surveys and trends observed, such as the increasing acceptance of methotrexate as first line drug of choice in patients with RA, especially if the disease is of an aggressive nature. The newer anti-TNF agents have also begun to be incorporated into use. The incremental cost-effectiveness ratios resulting from the use of an inappropriate comparator of placebo were consistently lower than in the base case where appropriate comparator drugs sequences are used. The focus of the BRAM on a drug sequence helped to avoid the incremental cost-effectiveness of new treatments appearing lower than they really are when inappropriate comparators are used. To test the effect on the analysis results of using the disease-modifying antirheumatic sequence that represents current UK practice, the BRAM was run for the strategies representing current UK practice. The results were not very different from the base-case results. CONCLUSIONS: The main achievement of this work was to bring about a more realistic modelling of real-life clinical pathways and events, as it has developed from the BPM to the BRAM. This has been brought about by overcoming structural and data limitations. In addition, the modelling approach reflected in the BRAM is applicable to other chronic conditions, especially those where a sequential approach to therapeutic options exists. The model has been successfully restructured so that different sequences of treatment can readily be considered, including the sequence that best represents current clinical practice in the UK. In addition, the flexibility inherent in using a modelling approach to consider these health policy questions has been demonstrated. One of the key uncertainties that can now be explored concerns the impact of new drugs on disease progression. Current evidence on this is weak, but should new agents demonstrate such a benefit then the BRAM may be a suitable vehicle through which to investigate the costs and full effects. Inevitably, there remain problems and limitations with the BRAM, but these are almost entirely data limitations. As data on these issues become available the BRAM provides a convenient tool through which reanalysis might be undertaken.

Adolescent↗
PubMed2004

Materials used in drinking water distribution systems: contribution to taste-and-odor.

In order to assist drinking water utilities with identifying the possible sources and causes of taste-and-odor conditions associated with materials used in distribution systems, we evaluated information from case studies and a database from the National Sanitation Foundation (NSF), International. This database identified chemicals that had leached from drinking water system components during testing of materials under ANSI/NSF Standard 61, which provides information to water utilities on potential taste-and-odor and health concerns from the use of new materials. The data were arranged to provide a process for locating the potential source of a taste-and-odor event. After a sensory analysis is conducted on the drinking water samples, the descriptor can be matched with categories on the "Drinking Water Taste and Odor Wheel 2000" in order to suggest the candidate material.

Databases, Factual↗
PubMed2003

A survey of British rheumatologists' DMARD preferences for rheumatoid arthritis.

OBJECTIVE: To determine the current disease-modifying anti-rheumatic drug (DMARD) preferences of UK consultant rheumatologists. METHODS: A questionnaire was sent in May 2002. We asked which DMARD(s) was most frequently preferred first and sought the most typical sequence of DMARDs, including DMARD combinations. Also we determined the extent to which prognostic and other factors influenced treatment choices. Comments were invited, written responses abstracted and key themes identified. RESULTS: After two mailings, 331 (of 460; 72%) suitable questionnaires were returned. Ninety-five per cent (315/331) preferred methotrexate (154, 46.5%) or sulphasalazine (144, 43.5%) or either of these two (17, 5%) as first-choice agent. Of those who chose methotrexate first, 80% (123/154) ranked sulphasalazine second, 45% (55/123) combined sulphasalazine and methotrexate and 49% (27/55) then added hydroxychloroquine to this combination, in active disease. Of those who chose sulphasalazine first, 95% (137/144) ranked methotrexate second, 75% (113/150) preferring methotrexate monotherapy and 12% (18/150) the combination with sulphasalazine. Rheumatologists who preferred sulphasalazine first more commonly used subsequent DMARDs singly than those who started with methotrexate (P < 0.0001). Leflunomide was more commonly preferred than intramuscular gold as third choice (52/145 vs 29/145; P < 0.003). The most popular sequence of DMARDs was methotrexate or sulphasalazine, singly or in combination, leflunomide, intramuscular gold and anti-tumour necrosis factor therapy. Poor prognostic factors influenced DMARD choice, but patient occupation and drug costs did not. CONCLUSION: Methotrexate has displaced other DMARDs, especially sulphasalazine, as agent of first choice and newer agents have displaced older DMARDs. Whether the expressed preference for particular DMARDs accurately reflects actual use, and is optimal in rheumatoid arthritis, remains to be determined.

Antirheumatic Agents↗
PubMed2003

Interleukin 10 polymorphisms in ankylosing spondylitis.

Genetic polymorphisms of the IL10 promoter region have been implicated in many autoimmune diseases, including seronegative spondyloarthropathies. We studied three SNPs (IL10-1087, -824, and -597) and two microsatellites (IL10R and IL10G) lying within the promoter region of IL10 for association with susceptibility to and clinical manifestations of ankylosing spondylitis (AS), a common form of spondyloarthritis. Four hundred and sixty-eight individuals from 182 Finnish families affected with AS were studied. No association between individual IL10 promoter region polymorphisms or marker haplotype was observed with susceptibility to AS, but weak association was noted between the IL10-597 and -824 SNPs and age of disease onset (P=0.01 for each SNP). The IL10.G4 allele was associated with BASFI (corrected for disease duration) (P=0.03). We conclude that IL10 promoter polymorphisms have no significant effect on susceptibility to AS, but may play a minor role in determining age of disease onset and disease severity.

Alleles↗
PubMed2003

Fine-scale genetic structure and gene flow within Costa Rican populations of mahogany (Swietenia macrophylla).

Fine-scale structure of genetic diversity and gene flow were analysed in three Costa Rican populations of mahogany, Swietenia macrophylla. Population differentiation estimated using AFLPs and SSRs was low (38.3 and 24%) and only slightly higher than previous estimates for Central American populations based on RAPD variation (20%). Significant fine-scale spatial structure was found in all of the surveyed mahogany populations and is probably strongly influenced by the limited seed dispersal range of the species. Furthermore, a survey of progeny arrays from selected mother trees in two of the plots indicated that most pollinations involved proximate trees. These data indicate that very little gene flow, via either pollen or seed, is occurring between blocks of mahogany within a continuous or disturbed forest landscape. Thus, once diversity is removed from a forest population of mahogany, these data suggest that recovery would be difficult via seed or pollen dispersal, and provides an explanation for mahogany's apparent susceptibility to the pressures of logging. Evidence is reviewed from other studies of gene flow and seedling regeneration to discuss alternative extraction strategies that may maintain diversity or allow recovery of genetic resources.

Biological Evolution↗
PubMed2003

Semi-automated software for the three-dimensional delineation of complex vascular networks.

The understanding of tumour angiogenesis is of great importance in cancer research, as is the tumour response to vascular-targeted drugs. This paper presents software aimed at aiding these investigations and other situations where linear or dendritic structures are to be delineated from three-dimensional (3D) data sets. This software application was written to analyse the data from 3D data sets by allowing the manual and semi-automated tracking and delineation of the vascular tree, including the measurement of vessel diameter. A new algorithm, CHARM, based on a compact Hough transform and the formation of a radial map, has been used to locate vessel centres and measure diameters automatically. The robustness of this algorithm to image smoothing and noise has been investigated.

Blood Vessels↗
PubMed2003

Device-related sources of bacteraemia in English hospitals--opportunities for the prevention of hospital-acquired bacteraemia.

Between 1997 and 2001, 17 teaching and 56 non-teaching acute English hospitals conducted hospital-wide surveillance of hospital-acquired bacteraemia (HAB) using a standard protocol drawn up by the Nosocomial Infection National Surveillance Scheme (NINSS). The sources of organisms, the incidence of device-related HAB, and the distribution of HABs from individual device-related sources by specialty and type of hospital were determined for 6,956 HABs in order to identify where resources should best be targeted to reduce these infections. The overall incidence of HAB was higher in teaching than in non-teaching hospitals: 5.39 and 2.83 HABs per 1,000 patients at risk, respectively (P<0.001). Device-related sources were responsible for 52.4 and 43.2% of all HABs in teaching and non-teaching hospitals, respectively (P<0.001), and central lines were the commonest source, causing 38.3% of HABs in teaching versus 22.3% in non-teaching hospitals (P<0.001). In teaching hospitals, general intensive care units (ICUs), haematology, special care baby units (SCBUs), nephrology, and oncology accounted for only 6.1% of the population surveyed, but had the highest incidence of HAB, and contributed 47.8% of 2091 HABs and 56.9% of 1,095 device-related bacteraemias. Of 623 device-related bacteraemias in these high-risk specialties, 554 (88.9%) were from central lines. Thus, in teaching hospitals, resources should be targeted primarily at the prevention of central line-related bacteraemia in these five high-risk specialties, and the surveillance should include data on central line use. In non-teaching hospitals, nearly two thirds (63.3%) of 4,865 HABs and 60.7% of 2,103 device-related bacteraemias were from a few specialties with a low incidence of bacteraemia, but large numbers of patients, namely general medicine, general surgery, geriatric medicine and urology. These specialties accounted for 50.5% of the population surveyed. Central lines were the most common source of bacteraemia in general medicine and surgery, and together accounted for 23.3% of all device-related bacteraemias. However, in geriatric medicine and urology, central line sources were infrequent, accounting for only 1.7% of all device-related bacteraemias. On the other hand, bacteraemia from catheter-associated UTI were common in all these four specialties accounting for 20.9% of all device-related bacteraemias. Thus, in non-teaching hospitals, resources should be targeted primarily at these low-risk specialties and surveillance should include, at least, bacteraemia from central lines and from catheter-associated UTI. Further benefit can be obtained by including central line-related bacteraemias from general ICU and haematology patients, as they contributed 17.0% of all device-related bacteraemias in non-teaching hospitals.

Bacteremia↗
PubMed2003

The efficacy of bacitracin methylene disalicylate when fed in combination with narasin in the management of necrotic enteritis in broiler chickens.

The efficacy of bacitracin methylene disalicylate (BMD) in the management of necrotic enteritis (NE) when fed in combination with narasin was investigated in a floor-pen study of 2,000 broiler chickens using a Clostridium perfringens inoculum challenge model. Treatments consisted of 1) nonchallenged-nonmedicated; 2) challenged-nonmedicated; 3) challenged-narasin (70 ppm); 4) challenged-BMD (55 ppm); 5) challenged-narasin (70 ppm) + BMD (55 ppm). Medication was provided in the feed from Day 0 to trial termination on Day 41. C. perfringens challenge occurred from Day 14 to 16. BMD and narasin, fed alone and in combination, reduced (P < 0.05) mortality due to NE when compared to challenged-nonmedicated birds. NE lesion scores (Days 0 through 41) were lower among birds fed BMD and narasin, alone and in combination, compared to challenged-nonmedicated birds. Improvements in NE mortality and NE lesion scores were greatest for the BMD + narasin-medicated birds, followed by the BMD-alone, and then narasin-alone treated birds. BMD and narasin, alone and in combination, provided improvements (P < 0.05) in average daily gains over the entire study (Days 0 to 41). The results of this study demonstrate the effectiveness of BMD and narasin in the management of NE in broiler chickens.

Animals↗
PubMed2003

Treatment of neurosyphilis with ceftriaxone.

The first choice treatment for late syphilis is penicillin. Other than doxycycline, which penetrates the CNS, there are few alternatives for the treatment of neurosyphilis. We report a case of successful treatment of symptomatic neurosyphilis with parenteral ceftriaxone.

Antitreponemal Agents↗
PubMed2003

Quantitative analysis of three-dimensional conformal radiotherapy techniques for posterior fossa treatment in children.

Numerous beam directions using 3-D conformal techniques can be employed in treating tumors in the posterior fossa, each with characteristic normal tissue exposure along the entrance and exit trajectory. A representative variety of beam configurations were modeled in a modern computer planning system initially with the entire posterior fossa as the target. These beams were quantitatively scored using criteria based on integral doses for both low dose and high dose effects encompassing a variety of critical normal structures, thus identifying strengths and weaknesses of each beam. By blocking portions of a particular beam accounting for unfavorable scores, a map of "zones" within the posterior fossa ideally treated by a certain beam or beams could be constructed. No universally ideal photon beam arrangement for the entire posterior fossa target could be identified. However, using single beam analysis, the strengths and weaknesses of particular strategies could be quantified. For example, vertex beams treating the cerebellar hemispheres allow the greatest sparing of cochlea and hypothalamus but at the cost of increased low to moderate dose to the supratentorial brain. Using the constructed maps identifying "zones" appropriately treated by a given beam or beams, three-dimensional conformal treatment plans with favorable dose-volume statistics can be designed based on previously defined normal tissue tolerance considerations. It is shown how this approach can be individualized based on specific patient characteristics (e.g., age). We conclude that radiotherapy directed to the posterior fossa can be optimized based on systematic assessment of individual beam contributions to normal tissues. This technique allows fast selection of treatment beams based on known normal tissue anatomical and tolerance information. Further studies will be required regarding long term effects of various radiation doses on specific volumes of normal tissue in order to individualize beam selection. When treating children, knowledgeable consideration of these beam characteristics can help avoid late effects.

Child↗
PubMed2003

A field study of dietary interactions with monensin on milk fat percentage in lactating dairy cattle.

Ninety-one Ontario Holstein dairy herds were surveyed about their lactating cow ration and use of a premix containing monensin to identify possible dietary interactions with monensin on milk fat suppression. All herds were enrolled in Ontario Dairy Herd Improvement (DHI) milk recording, and results from four DHI tests were used. Herd mean fat tests were calculated only for cows between 100 and 200 d in milk to avoid potential confounding due to stage of lactation. Wet forage and total mixed ration (TMR) samples from all herds were evaluated for particle size using the Penn State Particle Size Separator. Of the herds using monensin (n = 58), the dose (per kg of dry matter) ranged from 9 to 14 mg/kg in TMR-fed herds and from approximately 9 to 23 mg/kg in herds in which concentrates were fed separately from forages (component-fed). Of the samples submitted for particle size evaluation, 15% of the haylage (n = 80), 14% of the corn silage (n = 79), and 42% of the TMR (n = 58) samples were classified as having low fiber. There was a significant negative univariable association between monensin and mean milk fat percentage. Monensin significantly reduced milk fat percentage in TMR-fed but not component-fed herds. Fiber length significantly interacted with monensin in TMR-fed herds: Herds that had low fiber in their TMR (< or = 6.0% in the top screen) were susceptible to milk fat decrease by monensin, whereas herds that had adequate fiber (> 6.0%) were not. Monensin also significantly reduced milk fat percentage in herds receiving diets low in nonstructural carbohydrate (< 40.2%) but not in those receiving diets high in NSC (> or = 40.2%). The results of this study suggest that there are significant interactions between monensin and certain dietary factors on milk fat suppression in Holstein dairy herds.

Animals↗
PubMed2002

Radiotherapy versus open surgery versus endolaryngeal surgery (with or without laser) for early laryngeal squamous cell cancer.

BACKGROUND: Radiotherapy, open surgery and endolaryngeal excision (with or without laser) are all accepted modalities of treatment for early stage glottic cancer. Case series suggest that they confer similar survival advantage. Opinions on optimal therapy vary across disciplines and between countries. OBJECTIVES: To compare the effectiveness of open surgery, endolaryngeal excision (with or without laser) and radiotherapy in the management of early glottic laryngeal cancer SEARCH STRATEGY: Electronic search of MEDLINE (from 1966 to October 2000), EMBASE (from 1980 to October 2000), CINAHL (from 1982 to October 2000) and CancerLit (from 1963 to October 2000) databases and the Cochrane Controlled Trials Register. SELECTION CRITERIA: Randomised controlled trials (RCT) comparing open surgery, endolaryngeal resection and/or radiotherapy DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed RCTs identified from the electronic searches for eligibility and methodological quality. All authors of the review discussed the results of these assessments. MAIN RESULTS: Only one RCT was identified which compared open surgery and radiotherapy among a substantial number of patients with early glottic laryngeal cancer. REVIEWER'S CONCLUSIONS: There is currently insufficient evidence to guide management decisions on the most effective treatment. Interpretation of the only large scale RCT comparing open surgery and radiotherapy in patients with early glottic cancer is limited because of concerns about the adequacy of treatment regimens and deficiencies in the reporting of the study design and analysis. Endolaryngeal resection of early glottic tumours is becoming more common and a well designed multicentre RCT is warranted.

Carcinoma, Squamous Cell↗
PubMed2002

Analysis of 3-hydroxydodecanedioic acid for studies of fatty acid metabolic disorders: preparation of stable isotope standards.

Current diagnostic tests to detect disorders of fatty acids metabolism, such as long-chain hydroxyacyl CoA dehydrogenase deficiency (LCHAD), are hampered by insensitivity or a long delay time required for results. Children with LCHAD deficiency are known to excrete 3-hydroxydicarboxylic acids with chain lengths of 10-16 carbons, but a quantitative method to measure excretion of these potentially diagnostically important compounds has not been reported. We report synthetic schemes for synthesis of 3-hydroxydodecanedioic acid and a di-deuterated analog, suitable for use in a stable-isotope dilution mass spectrometric analytical approach. Evaluation of several common derivatization protocols to produce a volatile derivative for gas chromatography determined that trimethylsyl derivatives produced the best efficiency and stability. Positive-ion chemical ionization mass spectrometry provided the greatest yield of characteristic ions. These results indicate the basic reagents needed to develop sensitive and accurate 3-hydroxydodecanedioic acid measurements for diagnosis of LCHAD deficiency and other fatty acid oxidation disorders.

3-Hydroxyacyl CoA Dehydrogenases↗
PubMed2002

Hypertension is frequently present in patients with reflux esophagitis or Barrett's esophagus but not in those with non-ulcer dyspepsia.

BACKGROUND: Elevated mortality due to cardiovascular disease has been reported for patients with Barrett's esophagus (BE). We compared the prevalence of risk factors for cardiovascular disease in patients with BE, reflux esophagitis (RE), and non-ulcer dyspepsia (NUD) with that of the general population. METHODS: Patients with upper gastrointestinal complaints and BE, RE, or NUD were compared with a matched cohort from the general population using a questionnaire and blood pressure and cholesterol measurements. RESULTS: Hypertension occurred more frequently in patients with BE (odds ratio 5.1, P<0.0001) and RE (odds ratio 3.8, P<0.001), but not in those with NUD. Serum total cholesterol was higher in BE (P=0.02) and borderline in RE (P=0.06) but not in NUD. Mean HDL cholesterol levels, body mass index, and smoking did not differ. CONCLUSIONS: This study suggests that BE and RE found at diagnostic endoscopy are associated with an increased prevalence of hypertension and a higher total cholesterol level than in the general population. If so, this would explain the increased mortality during the follow-up of BE patients, and it should be taken into account when designing or evaluating follow-up studies of BE.

Journal Article↗
PubMed2002

Evaluation of Bioglass/dextran composite as a bone graft substitute.

Allogenic and alloplastic bone graft substitutes serve either as bioinert or bioactive osteoconductors. Bioglass is a bioactive osteoconductor and also shows osteoproductive effects due to its high level of bioactivity. However, the material lacks some cohesiveness when used in augmenting certain bony surfaces, i.e. large or pleomorphic defects. The addition of medium molecular weight dextran modifies the particulate to a putty consistency and improves the handling characteristics. The objective of this study is to evaluate the influence of dextran upon the bioactive properties of Bioglass. Standardized bony defects in the lateral femoral condyles in adult New Zealand white rabbits were filled with one of five material groups: (1) autogenous bone; (2) Bioglass particulate; (3) Bioglass particulate mixed with dextran to a putty-like consistency; (4) a mixture of Bioglass and autogenous bone; (5) a mixture of Bioglass putty with autogenous bone. Postoperative healing was observed after periods of 2 days, 1, 2, 3, 6 and 12 weeks. Results showed no evidence of toxicity in the dextran-containing materials, and defects in all test groups showed 100% bony ingrowth within 6 weeks. The addition of medium molecular weight dextran did not appear to alter the bioactive properties of Bioglass and had no adverse influence upon the ingrowth of bone into the defect sites.

Animals↗