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Jeremy Miles

Publications and source records attributed to Jeremy Miles.

10 recordsLinked to original sources
PubMed2005

Is the presence of urinary indolyl-3-acryloylglycine associated with autism spectrum disorder?

To test whether the presence of indolyl-3-acryloylglycine (IAG) is associated with autism, we analyzed urine from population-based, blinded cohorts. All children in York, UK with autism spectrum disorders (ASDs), diagnosed using ICD-10 research diagnostic criteria, were invited to participate. Fifty-six children on the autism spectrum (mean age 9y 8mo, SD 3y 8mo; 79% male) agreed to participate, as did 155 children without ASDs (mean age 10y, SD 3y 2mo; 54% male) in mainstream and special schools (56 of whom were age-, sex-, and school-matched to children with ASDs). IAG was found at similar levels in the urine of all children, whether IAG concentrations or IAG:creatinine ratios were compared. There was no significant difference between the ASD and the comparison group, and no difference between children at mainstream schools and those at special schools. There is no association between presence of IAG in urine and autism; therefore, it is unlikely to be of help either diagnostically or as a basis for recommending therapeutic intervention with dietary manipulation. The significance of the presence of IAG in urine has yet to be determined.

Adolescent↗
PubMed2005

Effects of emotional disclosure on psychological and physiological outcomes in patients with rheumatoid arthritis: an exploratory home-based study.

The effects of an exploratory, home-based emotional disclosure intervention on psychological and physiological outcomes were assessed in patients with rheumatoid arthritis. Patients were randomly assigned to a disclosure group (n = 19) in which they wrote/talked about traumatic personal experiences, or to a control group (n = 15) in which they wrote/talked about the events of a particular day. Participants undertook these tasks for periods of 20 minutes on 4 consecutive days. The disclosure group demonstrated increases in negative mood and objective markers of disease activity at 1 week post-intervention. However, there were significant trends for the disclosure group to demonstrate minor improvements in mood and stability in disease activity, compared with the control group. These group differences appeared to be due to deteriorations in the control group more than improvements in the disclosure group.

Activities of Daily Living↗
PubMed2005

Diagnostic criteria and staging of hand-arm vibration syndrome in the United Kingdom.

In the United Kingdom the diagnosis of Hand-arm Vibration Syndrome varies depending on the purpose of that diagnosis. The criteria differ in three situations. More than 100,000 miners and ex-miners with claims for HAVS have been examined using a Medical Assessment Process which included the use of standardised tests. This contract is unique but it has had significant effects on the two other processes. The Industrial Injuries Disablement Benefit Scheme provides a benefit that can be paid to an employed earner because of an accident or Prescribed Disease. New recommendations have been published to remove the anomalies in the present format for assessing HAVS. If implemented the new scheme will recognise the Stockholm Workshop Scales and workers with neurological problems will also be compensated. The Health and Safety Executive will issue new guidance in the near future on the hazards of hand-arm vibration. Health surveillance in the workplace will be fundamental and the HSE propose a tiered approach with levels 1 to 5. Specialist occupational nurses and doctors with training in the diagnosis and assessment of HAVS will be needed for levels 3 and 4. Only at this level may a diagnosis of HAVS be made. The Medical Assessment Process has demonstrated that it is possible to examine a large number of claimants in a standardised manner. The IIAC and HSE recommendations contain very important improvements on the existing positions in the UK and it must be hoped that they will be implemented in the near future.

Arm↗
PubMed2004

NHS Direct versus general practice based triage for same day appointments in primary care: cluster randomised controlled trial.

OBJECTIVE: To assess the relative effects on consultation workload and costs of off-site triage by NHS Direct for patients requesting same day appointments compared with usual on-site nurse telephone triage in general practice. DESIGN: Cluster randomised controlled trial. SETTING: Three primary care sites in York, England. PARTICIPANTS: 4703 patients: 2452 with practice based triage, 2251 with NHS Direct triage. All consecutive patients making requests for same day appointments during study weeks were eligible for the trial. MAIN OUTCOME MEASURES: Type of consultation after request for same day appointment (telephone, appointment, or visit); time taken for consultation; service use during the month after same day contact; costs of same day, follow up, and emergency care. RESULTS: Patients in the NHS Direct group were less likely to have their call resolved by a nurse and were more likely to have an appointment with a general practitioner. Mean total time per patient in the NHS Direct group was 7.62 minutes longer than in the practice based group. Costs were greater in the NHS Direct group--2.88 pounds sterling (0.88 pounds sterling to 4.87 pounds sterling) per patient triaged--as a result of the difference between the groups in proportions of patients at each final point contact after triage. CONCLUSIONS: External management of requests for same day appointments by nurse telephone triage through NHS Direct is possible but comes at a higher cost than practice nurse delivered triage in primary care. If NHS Direct could achieve the same proportions of consultation types as practice based triage, costs would be comparable.

Adolescent↗
PubMed2003

A framework for power analysis using a structural equation modelling procedure.

BACKGROUND: This paper demonstrates how structural equation modelling (SEM) can be used as a tool to aid in carrying out power analyses. For many complex multivariate designs that are increasingly being employed, power analyses can be difficult to carry out, because the software available lacks sufficient flexibility. Satorra and Saris developed a method for estimating the power of the likelihood ratio test for structural equation models. Whilst the Satorra and Saris approach is familiar to researchers who use the structural equation modelling approach, it is less well known amongst other researchers. The SEM approach can be equivalent to other multivariate statistical tests, and therefore the Satorra and Saris approach to power analysis can be used. METHODS: The covariance matrix, along with a vector of means, relating to the alternative hypothesis is generated. This represents the hypothesised population effects. A model (representing the null hypothesis) is then tested in a structural equation model, using the population parameters as input. An analysis based on the chi-square of this model can provide estimates of the sample size required for different levels of power to reject the null hypothesis. CONCLUSIONS: The SEM based power analysis approach may prove useful for researchers designing research in the health and medical spheres.

Analysis of Variance↗
PubMed2003

An investigation into the relationship between salivary cortisol, stress, anxiety and depression.

This study examined the relationship between indices of self-reported emotional distress and absolute versus change in cortisol levels. Fifty-four women attending a diagnostic breast clinic completed scales measuring stress, anxiety and depression and provided five saliva samples over the course of a single day for the measurement of cortisol. No significant relationships were evident between absolute cortisol levels and the distress measures. Analysis of the change in cortisol levels revealed a non-linear interaction effect between stress and anxiety and time of day. There was a non-linear relation between time of day and cortisol levels, but the extent of the non-linearity was dependent upon levels of stress and anxiety, not depression. A relationship was apparent between indices of distress and change in cortisol levels, but not absolute levels of the hormone.

Adult↗
PubMedDate not supplied

Pyropheophorbide 2-deoxyglucosamide: a new photosensitizer targeting glucose transporters.

To prepare near-infrared fluorescence imaging and photodynamic therapy agents targeted at glucose transporters, pyropheophorbide 2-deoxyglucosamide (Pyro-2DG) was synthesized and evaluated in a 9L glioma rat model. Fluorescence imaging studies demonstrate that Pyro-2DG is selectively accumulated in the tumor. Upon its photoactivation, we demonstrate that this agent efficiently causes selective mitochondrial damage to the region of a tumor that was photoirradiated after administration of this agent, but does not affect tissues photoirradiated in the absence of the agent or tissues treated with the agent that are not photoirradiated. Preliminary confocal microscopy studies suggest that Pyro-2DG is delivered and trapped in tumor cells via the GLUT/hexokinase pathway and therefore is useful both as a tumor-targeted NIR fluorescence imaging probe and as a PDT agent for the destruction of cancer.

Animals↗
PubMedDate not supplied

Broadband reflectance measurements of light penetration, blood oxygenation, hemoglobin concentration, and drug concentration in human intraperitoneal tissues before and after photodynamic therapy.

We evaluate Photofrin-mediated photodynamic therapy (PDT) in a phase 2 clinical trial as an adjuvant to surgery to treat peritoneal carcinomatosis. We extract tissue optical [reduced scattering (mu(s)'), absorption (mu(a)), and attenuation coefficients (mu(eff))] and physiological [blood oxygen saturation (%S(t)O2), total hemoglobin concentration (THC), and photosensitizer concentration (c(Photofrin))] properties in 12 patients using a diffuse reflectance instrument and algorithms based on the diffusion equation. Before PDT, in normal intraperitoneal tissues %S(t)O2 and THC ranged between 32 to 100% and 19 to 263 microM, respectively; corresponding data from tumor tissues ranged between 11 to 44% and 61 to 224 microM. Tumor %S(t)O2 is significantly lower than oxygenation of normal intraperitoneal tissues in the same patients. The mean (+/-standard error of mean) penetration depth (delta) in millimeters at 630 nm is 4.8(+/-0.6) for small bowel, 5.2 (+/-0.67) for large bowel, 3.39(+/-0.29) for peritoneum, 5.19(+/-1.4) for skin, 1.0(+/-0.1) for liver, and 3.02(+/-0.66) for tumor. c(Photofrin) in micromolars is 4.9(+/-2.3) for small bowel, 4.8(+/-2.3) for large bowel, 3.0 (+/-1.0) for peritoneum, 2.5(+/-0.9) for skin, and 7.4(+/-2.8) for tumor. In all tissues examined, mean c(Photofrin) tends to decrease after PDT, perhaps due to photobleaching. These results provide benchmark in-vivo tissue optical property data, and demonstrate the feasibility of in-situ measurements during clinical PDT treatments.

Algorithms↗
PubMedDate not supplied

Optical properties of human prostate at 732 nm measured in mediated photodynamic therapy.

Characterization of the tissue light penetration in prostate photodynamic therapy (PDT) is important to plan the arrangement and weighting of light sources so that sufficient light fluence is delivered to the treatment volume. The optical properties (absorption [mu(a)], transport scattering [mu(s)'] and effective attenuation [mu(eff)] coefficients) of 13 patients with locally recurrent prostate cancer were measured in situ using interstitial isotropic detectors. Measurements were made at 732 nm before and after motexafin lutetium (MLu)-mediated PDT in four quadrants. Optical properties were derived by applying the diffusion theory to the fluence rates measured at several distances (0.5-5 cm) from a point source. mu(a) and mu(s)' varied between 0.07 and 1.62 cm(-1) (mean 0.37 +/- 0.24 cm(-1)) and 1.1 and 44 cm(-1) (mean 14 +/- 11 cm(-1)), respectively. mu(a) was proportional to the concentration of MLu measured by an ex vivo fluorescence assay. We have observed, on average, a reduction of the MLu concentration after PDT, presumably due to the PDT consumption of MLu. mu(eff) varied between 0.91 and 6.7 cm(-1) (mean 2.9 +/- 0.7 cm(-1)), corresponding to an optical penetration depth (delta = 1/micro(eff)) of 0.1-1.1 cm (mean 0.4 +/- 0.1 cm). The mean penetration depth at 732 nm in human prostate is at least two times smaller than that found in normal canine prostates, which can be explained by a four times increase of the mean value of mu(s)' in human prostates. The mean light fluence rate per unit source strength at 0.5 cm from a point source was 1.5 +/- 1.1 cm(-2), excluding situations when bleeding occurs. The total number of measurements was N = 121 for all mean quantities listed above. This study showed significant inter- and intraprostatic differences in the optical properties, suggesting that a real-time dosimetry measurement and feedback system for monitoring light fluences during treatment should be considered for future PDT studies.

Humans↗