Biomedical subjects

Christopher Roberts

Publications and source records attributed to Christopher Roberts.

7 recordsLinked to original sources

PubMed2006

A multicenter, prospective, randomized, double-blind, placebo-controlled trial of corticosteroids and intravenous cyclophosphamide followed by oral azathioprine for the treatment of pulmonary fibrosis in scleroderma.

OBJECTIVE: The lack of randomized controlled trials (RCTs) in pulmonary fibrosis in systemic sclerosis (SSc) has hampered an evidence-based approach to treatment. This RCT was undertaken to investigate the effects of intravenous (IV) cyclophosphamide (CYC) followed by azathioprine (AZA) treatment in pulmonary fibrosis in SSc. METHODS: Forty-five patients were randomized to receive low-dose prednisolone and 6 infusions (monthly) of CYC followed by oral AZA, or placebo. Primary outcome measures were change in percent predicted forced vital capacity (FVC) and change in single-breath diffusing capacity for carbon monoxide (DLCO). Secondary outcome measures included changes in appearance on high-resolution computed tomography and dyspnea scores. An intent-to-treat statistical analysis was performed. RESULTS: At baseline, there were no significant group differences in factors linked to outcome, including severity of pulmonary fibrosis and autoantibody status. Sixty-two percent of the patients completed the first year of treatment. Withdrawals included 9 patients (6 from the placebo group) with significant decline in lung function, 2 with treatment side effects (both from the active treatment group), and 6 with non-trial-related comorbidity. No hemorrhagic cystitis or bone marrow suppression was observed. Estimation of the relative treatment effect (active treatment versus placebo) adjusted for baseline FVC and treatment center revealed a favorable outcome for FVC of 4.19%; this between-group difference showed a trend toward statistical significance (P = 0.08). No improvements in DLCO or secondary outcome measures were identified. CONCLUSION: This trial did not demonstrate significant improvement in the primary or secondary end points in the active treatment group versus the group receiving placebo. However, for FVC there was a trend toward statistical significance between the 2 groups. This suggests that treatment of pulmonary fibrosis in SSc with low-dose prednisolone and IV CYC followed by AZA stabilizes lung function in a subset of patients with the disease. Therapy was well tolerated with no increase in serious adverse events.

Administration, Oral↗

PubMed2006

Cost-effectiveness of a supplementary class-based exercise program in the treatment of knee osteoarthritis.

OBJECTIVES: The aim of this study was to assess the cost-effectiveness of a class-based exercise program supplementing a home-based program when compared with a home-based program alone. In addition, we estimated the probability that the supplementary class program is cost-effective over a range of values of a decision maker's willingness to pay for an additional quality-adjusted life-year (QALY). METHODS: The resource use and effectiveness data were collected as part of the clinical trial detailed elsewhere. Unit costs were estimated from published sources. The net benefit approach to cost-effectiveness analysis is used to estimate the probability of the intervention being cost-effective. RESULTS: The addition of a supplementary class-based group results in an increase in QALYs and lower costs. For all plausible values of a decision maker's willingness to pay for a QALY, the supplementary class group is likely to be cost-effective. CONCLUSIONS: The addition of a class-based exercise program is likely to be cost-effective and, on current evidence, should be implemented.

Cost-Benefit Analysis↗

PubMed2006

Suicidal behaviour in youths with depression treated with new-generation antidepressants: meta-analysis.

BACKGROUND: Concern exists that antidepressants can cause suicidality in youths with depression. AIMS: To determine the pooled risk of self-harm and suicidal behaviour from randomised trials of newer antidepressants. METHOD: A meta-analysis was carried out to calculate odds ratios for the combined data. RESULTS: Self-harm or suicide-related events occurred in 71 of 1487 (4.8%) of depressed youths treated with antidepressants v. 38 of 1254 (3.0%) of those given placebo (fixed effects odds ratio 1.70, 95% CI 1.13-2.54, P=0.01). There was a trend for individual suicidal thoughts, attempts and self-harm to occur more often in youths taking antidepressants than in those given placebo, but none of these differences was statistically significant. CONCLUSIONS: Antidepressants may cause a small short-term risk of self-harm or suicidal events in children and adolescents with major depressive disorder.

Adolescent↗

PubMed2004

A novel assay to determine the sequence preference and affinity of DNA minor groove binding compounds.

Sequence-specific binding in the minor groove of DNA by small molecules is a growing area of research with possible therapeutic relevance. By selectively binding to DNA sequences required by critical transcription factors, these small molecules could potentially modulate the expression levels of disease-causing genes. Precise targeting of a critical transcription factor of a selected gene requires an understanding of the preferred sequence of the DNA binding compound. As new compounds are being synthesized, there is a need to evaluate their DNA recognition profile. We sought to establish a procedure to determine sequence preference of compounds with previously unknown binding properties. A novel procedure for determining the optimal DNA binding sequence of minor groove binding compounds is described here. The assay also allows for determination of the binding affinity to a particular sequence.

Base Sequence↗

PubMed2003

Why are patients in clinical trials of heart failure not like those we see in everyday practice?

BACKGROUND/OBJECTIVES: Evidence-based research has been criticized for not being relevant to the real world of patient care in the community, mainly because participants in research studies are dissimilar to those typically seen in every day practice. This article examines recruitment difficulties, and identifies the main reasons why patients with heart failure declined to participate in a research trial. METHODS: Postal survey of potential trial participants (n=667), at time of recruitment. Analysis of (1) clinical and sociodemographic characteristics of respondents and nonrespondents to survey, and decliners and consenters to participation in a randomized controlled trial. RESULTS: No significant differences were found between respondents and nonrespondents in respect to sociodemographic or clinical variables. Males (OR=1.58, CI=1.04-2.41), younger patients (OR=1.05, CI=1.03-1.08), and those prescribed an angiotensin converting enzyme (ACE) inhibitor (OR=1.68, CI=1.10-2.57) were significantly more likely to consent to participate. Main reasons for nonparticipation were perceptions of being too old, too unwell, or too busy. CONCLUSIONS: Explanations of the purpose of research need to counter against perceptions among participants and clarify the benefits and disadvantages of participating in an intervention study when unwell. Study design should recognize that many elderly patients have busy lives and caring responsibilities. Financial support for participation should be considered.

Aged↗

PubMed2002

Geometry optimisation of aluminium clusters using a genetic algorithm.

The application of a Genetic Algorithm, for optimising the geometry of aluminium clusters with 21-55 atoms bound by the many-body Murrell-Mottram potential, is described. In this size regime, a number of different structural motifs are identified--face-centred cubic, hexagonal close packed, decahedral and icosahedral structures. The larger clusters consist of hollow icosahedral geometric shells, with Al55 having a centred icosahedral structure. Evolutionary Progress Plots for Al19 and Al38 reveal how the best structure evolves from generation to generation upon operation of the Genetic Algorithm.

Journal Article↗

PubMed2002

DNA binding compounds targeting fungal pathogens: an emerging concept in the discovery of novel antifungal agents.

With the urgent need for novel agents to combat emerging fungal resistance to existing drugs, activity in the exploration of small molecule DNA binders has increased. Recently, selected cationic heterocyclic compounds belonging to a broad class of molecules known to bind to the minor groove of DNA were revealed to have potent antifungal activity. These molecules are different from the conventional DNA-interacting drugs such as topoisomerase inhibitors, DNA alkylators or intercalators. Selected compounds are fungicidal towards a variety of pathogenic yeasts and molds, and a selected lead compound is efficacious in a mouse model of systemic candidosis.

Animals↗