Biomedical subjects

R Blundell

Publications and source records attributed to R Blundell.

4 recordsLinked to original sources

PubMed2004

Emphysema: the challenge of the remodelled lung.

Emphysema is recognized as the component of chronic obstructive airways disease that is responsible for airways obstruction. Different patterns of emphysema are, however, recognized, suggesting possible different pathogenetic processes within the lung. This, coupled with the associated idea of susceptibility factors to the development of emphysema, has led to studies of genes that may be involved in the defence of the lung from proteolytic and oxidative damage. These studies have been driven by the goal of finding a treatment for emphysema, but appear to have lost sight of the fundamental remodelling of the lung that has occurred in patients with emphysema and the fact that it is not a single morphological entity.

Genetic Therapy↗

PubMed2000

Identifying demand for health resources using waiting times information.

In this paper the differences in average waiting times are utilized to identify the determinants of demand for health services. The equilibrium waiting time framework is used, but the full equilibrium assumption is relaxed by selecting areas with low waiting times and by estimating a (semi-)parametric selection model. Determinants of supply are used as instruments for the endogeneity of waiting times. A model for the demand for acute services at the ward level in the UK is estimated. The model estimates, and their implications for health service allocations in the UK, are contrasted against more standard allocation models. The present results show that it is critically important to account for rationing by waiting times when identifying needs from care utilization data.

Health Care Rationing↗

PubMed2000

Characterisation of lectin binding patterns of mouse bronchiolar and rat alveolar epithelial cells in culture.

Lung epithelial cell differentiation pathways remain unclear. This is due in part to the plasticity of these cells and the lack of markers which accurately reflect their differentiation status. The aim of this study was to determine if lectin binding properties are useful determinants of functional differentiation status in vitro. Mouse Clara cells were cultured for 5 days. During this time, no alteration in differentiation was evident by electron microscopy. No significant alteration in binding reactivity of Bauhinia purpurea (BPA), Maclura pomifera (MPA), Concanavalin A, Wheat germ or Helix pomatia lectins occurred in cultures compared with Clara cells in mouse lung tissue. In contrast, nitrotetrazolium blue reductase activity and CC10 expression declined in culture. Rat type II cells were cultured for 8 days. Between days 0 and 4, the number of type II cells identified by electron microscopy was constant at 70-80%, decreasing to 8% by day 6. In contrast, by day 4, only 42% cells retained alkaline phosphatase activity. BPA and MPA reactivity was altered at day 0 and day 4 respectively, compared with cells in situ. Therefore, the reactivity of lectins analysed here does not reflect functional differentiation status of cultured mouse Clara cells. However, BPA and MPA reactivity may be a sensitive indicator of alterations in rat type II cell differentiation in vitro.

Alkaline Phosphatase↗

PubMedDate not supplied

Cluster effects and simultaneity in multilevel models.

For small group sizes, the GLS estimator in multilevel models is biased and inconsistent when the random cluster effects are correlated with the regressors. A fixed effects approach, conditioning on the cluster effects, provides consistent estimates for the slope parameters. The two estimators are equivalent when group sizes are large. The same results obtain for two-stage estimation procedures that allow for some of the regressors to be simultaneously determined with the dependent variable. The GLS and fixed effects estimators are applied to data on acute care hospital utilization in the UK, allowing for health authority district effects.

Effect Modifier, Epidemiologic↗