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Biomedical subjects

N Rice

Publications and source records attributed to N Rice.

At least 19 recordsLinked to original sources
PubMed2007

Enhancing cell survival of atrazine degrading Rhodococcus erythropolis NI86/21 cells encapsulated in alginate beads.

AIMS: To develop a method to produce beads with encapsulated Rhodococcus erythropolis NI86/21 with high cell density, extended shelf life, ease of handling and good atrazine degradation capabilities in both liquid and in agricultural soil. METHODS AND RESULTS: Our findings show that the supplementary recovery step in nutrient broth media shortly after cell encapsulation facilitates cell survival in both wet and dry beads upon extended storage at 4 degrees C. Air drying has little or no impact on encapsulated R. erythropolis cell's ability to degrade atrazine in liquid or soil. Bead storage for periods extending up to 12 months at 4 degrees C did not affect the capacity of R. erythropolis encapsulated cells to degrade atrazine in either BMN or nonsterile soil extracts. Bentonite-amended beads formulated with 1% skim milk and exposed to the supplementary growth step, outperformed all other bead formats. These beads provided adequate numbers of vigorous R. erythropolis cells in either liquid or soil media to degrade atrazine. CONCLUSIONS: Supplementary growth in nutrient broth media immediately following cell encapsulation greatly enhances R. erythropolis cells survival in both wet and dry beads upon extended storage at 4 degrees C. Wet and dried beads have similar capacity for atrazine degradation, and their usefulness and appeal in agronomic practise will only be known after bioassay evaluation and successful demonstration at field scale using incurred residues. SIGNIFICANCE AND IMPACT OF THE STUDY: R. erythropolis NI86/21 encapsulated cells have the potential to reduce residual atrazine in soil, thereby minimizing the likelihood of off-site transport to ground or river water and reduce the loss of crops because of phytotoxicity of residual herbicide. Owing to their ease of handling, storage and possible compatibilities with pre-existing mechanical equipment, dried bead formats are ideally suited for agricultural and remediational applications.

Alginates↗
PubMed2001

An evaluation of hospital special-ventilation-room pressures.

OBJECTIVE: To quantitate the magnitude and consistency of positive (airflow out) and negative (airflow in) hospital special-ventilation-room (SVR) airflow. DESIGN: A room-pressure evaluation was conducted during two seasons on a total of 18 rooms: standard rooms, airborne infection isolation rooms, and protective environment rooms. The pressures were measured using a digital pressure gauge-piezoresistive pressure sensor that measured pressure differentials. With doors closed, the rooms were measured a minimum of 30 times each for a cooling season and a heating season. RESULTS: The standard rooms showed the least amount of variability in pressure differential, with an average of -0.2 Pa (median, -0.2 Pa), and an interquartile range (IQR) of 0.4 Pa. Airborne infection isolation rooms showed more variability in pressure, with an average of -0.3 Pa (median, -0.2 Pa) and an IQR of 0.5 Pa. Protective environment rooms had the greatest fluctuation in pressure, with an average of 8.3 Pa (median, 7.7 Pa) and an IQR of 8.8 Pa. Dramatic pressure changes were observed during this evaluation, which may have been influenced by room architectural differences (sealed vs unsealed); heating, ventilation, and air-conditioning zone interactions; and stack effect. CONCLUSION: The pressure variations noted in this study, which potentially affect containment or exclusion of contaminants, support the need for standardization of pressure requirements for SVRs. To maintain consistent pressure levels, creating an airtight seal and continuous pressure monitoring may be necessary.

Calibration↗
PubMed2001

Capitation and risk adjustment in health care financing: an international progress report.

In every system of health care, capitation payments have become the accepted tool used by health care purchasers in much of the developed world to determine prospective budgets. The policy prescription of capitation is perceived to address both equity objectives (of great importance in publicly funded systems of health care) and efficiency objectives (the dominant concern in competitive insurance markets). An examination of the current state of the art in 20 countries outside the United States in which health care capitation has been implemented confirms that capitation has assumed central importance within diverse systems of health care. In practice, however, the setting of capitation payments has been heavily constrained to date by poor data availability and unsatisfactory analytic methodology.

Australia↗
PubMed2001

Ethics and geographical equity in health care.

Important variations in access to health care and health outcomes are associated with geography, giving rise to profound ethical concerns. This paper discusses the consequences of such concerns for the allocation of health care finance to geographical regions. Specifically, it examines the ethical drivers underlying capitation systems, which have become the principal method of allocating health care finance to regions in most countries. Although most capitation systems are based on empirical models of health care expenditure, there is much debate about which needs factors to include in (or exclude from) such models. This concern with legitimate and illegitimate drivers of health care expenditure reflects the ethical concerns underlying the geographical distribution of health care finance.

Delivery of Health Care↗
PubMed2000

Derivation of a needs based capitation formula for allocating prescribing budgets to health authorities and primary care groups in England: regression analysis.

OBJECTIVE: To develop a weighted capitation formula for setting target allocations for prescribing expenditures for health authorities and primary care groups in England. DESIGN: Regression analysis relating prescribing costs to the demographic, morbidity, and mortality composition of practice lists. SETTING: 8500 general practices in England. SUBJECTS: Data from the 1991 census were attributed to practice lists on the basis of the place of residence of the practice population. MAIN OUTCOME MEASURES: Variation in age, sex, and temporary resident originated prescribing units (ASTRO(97)-PUs) adjusted net ingredient cost of general practices in England for 1997-8 modelled for the impact of health and social needs after controlling for differences in supply. RESULTS: A needs gradient based on the four variables: permanent sickness, percentage of dependants in no carer households, percentage of students, and percentage of births on practice lists. These, together with supply characteristics, explained 41% of variation in prescribing costs per ASTRO(97)-PU adjusted capita across practices. The latter alone explained about 35% of variation in total costs per head across practices. CONCLUSIONS: The model has good statistical specification and contains intuitively plausible needs drivers of prescribing expenditure. Together with adjustments made for differences in ASTRO(97)-PUs the model is capable of explaining 62% (35%+0.65% (41%)) of variation in prescribing expenditure at practice level. The results of the study have formed the basis for setting target budgets for 1999-2000 allocations for prescribing expenditure for health authorities and primary care groups.

Budgets↗
PubMed2000

Capitation and risk adjustment in health care.

Capitation and risk adjustment have become the chosen policy instruments to seek cost containment and equity of access for many developed health care systems. Increasingly, this entails the prospective setting of global budgets for the health care expenditures incurred by health care plans on behalf of their members. Methods of deriving such budgets are diverse and tailored to the specific circumstances of the health care system they seek to serve. This special issue presents a collection of papers devoted to issues surrounding the rationale, derivation, and implementation of capitation and risk adjustment methods of financing health care. These are discussed within the context of health care systems in eight countries, illustrating the range of interest in the topic. Undoubtedly, capitation and risk adjustment will become increasingly significant elements of virtually all systems of health care and we hope the collection of papers will help to stimulate further debate and research in this important and interesting area of health care financing.

Budgets↗
PubMed1999

Non- and semi-parametric estimation of age and time heterogeneity in repeated cross-sections: an application to self-reported morbidity and general practitioner utilization.

Patterns of self-reported morbidity and general practitioner (GP) utilization exhibit complex age, sex and time heterogeneity. Underlying patterns are often obscured by data which are overly 'rough' because of noise associated with adjacent year fluctuations. In this paper we describe methods to obtain smoothed estimates of age, time and birth-cohort effects using data from the General Household Survey (GHS), covering the period 1984-1995/6 inclusive. The methods outlined offer powerful analytic tools to research complex profiles or trends, particularly over age or time. The relationships of the morbidity and GP utilization measures with age, sex and survey year characteristics are estimated non-parametrically using roughness penalized least squares (RPLS). A semi-parametric extension of this model is used to estimate the effect of the morbidity variables on GP utilization. Tests are employed for various forms of age and time heterogeneity including birth-cohort effects. Linear age specifications are rejected for all variables and evidence is found of time heterogeneity in one of the morbidity measures--limiting long-standing illness (LS)--and GP utilization. The advantages of employing non- and semi-parametric estimations in the presence of complex relationships such as those observed for age and time profiles are discussed. Adoption of these techniques by applied econometricians working in health economics is encouraged.

Adult↗
PubMed1999

Do measures of self-reported morbidity bias the estimation of the determinants of health care utilisation?

Most national surveys of health care utilisation capture only self-reported measures of morbidity. If self-reported morbidity is measured with error, then the results of applied work may be misleading. In this paper we propose a model of the relationship between morbidity and health service utilisation which allows for reporting errors and simultaneity. Errors in self-reported morbidity are expressed as a function of person-specific reporting thresholds and recent contact with health services, arising because of better self-evaluation of current health status or a desire to justify consumption of a publicly-provided good. We demonstrate the bias in ignoring the potential problems of reporting errors and simultaneity for a variety of special cases, but in the general case the biases are of ambiguous sign. The empirical nature of these biases is investigated using limiting long-standing illness (LLI) and recent contact with a General Practitioner (GP) in two waves of The UK Health and Lifestyle Survey. Biomedical measures of functioning are used as objective indicators of health status. We find evidence of substantial and significant differences between individuals in reporting thresholds and some evidence that the reporting of LLI may depend on recent visits to a GP. Adjustments for these biases significantly increase the estimated effect of morbidity on utilisation.

Adult↗
PubMed1998

Drinking patterns within households: the estimation and interpretation of individual and group variables.

Levels of alcohol consumption tend to be similar for individuals living in the same household. This may be because: (a) individuals with similar characteristics collect in households (correlated effects); (b) individuals in the same household are influenced by common factors (exogenous effects); and/or (c) the consumption levels of an individual directly influences the consumption levels of other individuals in the same household (endogenous effects). Whichever of these three possibilities is the principal reason underlying household clustering of consumption levels has important policy implications. In this paper we propose a testing strategy to distinguish between the three types of effect in a cross-sectional data-set. Allowing for exogenous or endogenous effects shows that the significant socio-economic gradient in a model containing only individual variables arises because of misspecification. However, because we find significant evidence of correlated effects, we cannot identify whether it is endogenous or exogenous effects which give rise to statistically significant group level variables. The results indicate the possible pitfalls of omitting group level influences.

Adult↗
PubMed1998

The influence of households on drinking behaviour: a multilevel analysis.

This paper examines the influence of household membership and area of residence on individual drinking behaviour using a multilevel modelling approach. The effects are investigated using data from the Health Survey for England (HSE) in which multiple interviews were conducted in the same household. With the use of postal address, the data were organised into a hierarchical structure of individuals within households within enumeration districts. After controlling for characteristics of individuals thought to influence or correlate with drinking behaviour, unexplained variation in alcohol consumption was attributed to individual, household and area effects. Household influences on drinking behaviour far outweigh the influences of place of residence. Policies aimed at reducing alcohol consumption, particularly by heavy drinkers, may be best targeted at the household level.

Adolescent↗
PubMed1998

Risk and the general practitioner budget holder.

For most individuals, the use made of health care in a given year is determined principally by unpredictable random incidents. Of course, some individuals have a predictably higher predisposition to illness than others. However, the general consensus is that only a fraction of individual variability in health care costs can be predicted. The purpose of this paper is to explore the implications of this inherent randomness for setting health care budgets for general practitioner purchasers of health care. The paper argues that variability in utilization in health care is very high: that no capitation formula can ever completely capture that variability, even for large populations: that the variability may give rise to certain dysfunctional consequences if not managed carefully; and that therefore careful attention should be given to the managerial arrangements associated with any devolution of health care budgets.

Budgets↗
PubMed1998

Receptor-specific induction of NF-kappaB components in primary B cells.

The NF-kappaB transcription factor complex plays a key role in the expression of genes involved in immune responses. Nuclear NF-kappaB is induced in B lymphocytes by engagement of either the antigen receptor (sIg) or the CD40 receptor for a T cell activation antigen, although different intracellular pathways appear to be involved. In the present study the protein composition of NF-kappaB complexes triggered by sIg and CD40 was probed by electrophoretic mobility shift, supershift, shift-Western, and Western blot analyses. At the time of peak NF-kappaB induction (2 h), the NF-kappaB components detected in the complexes induced through sIg and through CD40 were the same. However, with continued stimulation RelB completely disappeared from anti-Ig-stimulated kappaB binding material, but remained a component of CD40L-induced NF-kappaB. The loss of DNA-binding RelB from anti-Ig-induced NF-kappaB did not result from depletion of RelB from B cell nuclei, suggesting specific regulation of RelB function which is not directly attributed to IkappaB function. These results indicate that NF-kappaB complexes may undergo protein-specific alterations in a time- and receptor-dependent fashion that may be associated with differences in the outcomes of B cell stimulation through sIg and CD40.

Animals↗
PubMed1997

Interaction of NF-kappaB and NFAT with the interferon-gamma promoter.

Interferon-gamma (IFN-gamma) is a pleiotropic lymphokine whose production is restricted to activated T cells and NK cells. Along with other cytokines, IFN-gamma gene expression is inhibited by the immunosuppressant cyclosporin A. We have previously identified an intronic enhancer region (C3) of the IFN-gamma gene that binds the NF-kappaB protein c-Rel and that shows partial DNA sequence homology with the cyclosporin A-sensitive NFAT binding site and the 3'-half of the NF-kappaB consensus site. Sequence analysis of the IFN-gamma promoter revealed the presence of two additional C3-related elements (C3-1P and C3-3P). In addition, an NF-kappaB site (IFN-gamma kappaB) was identified within the promoter region. Based on this observation, we have analyzed the potential role of NF-kappaB and NFAT family members in regulating IFN-gamma transcription. Electrophoretic mobility shift assay analysis demonstrated that after T cell activation, the p50 and p65 NF-kappaB subunits bind specifically to the newly identified IFN-gamma kappaB and C3-related sites. In addition, we identified the NFAT proteins as a component of the inducible complexes that bind to the C3-3P site. Site-directed mutagenesis and transfection studies demonstrate that calcineurin-inducible transcriptional factors enhance the transcriptional activity of the IFN-gamma promoter through the cyclosporin-sensitive C3-3P site, whereas NF-kappaB proteins functionally interact with the C3-related sites. In addition, when located downstream to the beta-galactosidase gene driven by the IFN-gamma promoter, the intronic C3 site worked in concert with both the IFN-gamma kappaB and the C3-3P site to enhance gene transcription. These results demonstrate that the coordinate activities of NFAT and NF-kappaB proteins are involved in the molecular mechanisms controlling IFN-gamma gene transcription.

Base Sequence↗
PubMed1997

Informing prescribing allocations at district level in England.

OBJECTIVES: To derive a predictive model based on the morbidity, demographic and socio-economic characteristics of district populations to explain variations in prescribing costs in England. METHOD: Inter-relations between morbidity, demographic, socio-economic, general practice supply characteristics and net ingredient cost per age, sex and temporary resident originated prescribing unit (ASTRO-PU) were explored statistically for 90 districts in England using 1994 cost data. The possibility of mutual inter-relationship between 'supply' and 'demand' was examined; then the associations between a range of factors and prescribing costs were estimated using ordinary least squares regression and the predictive power of the possible models was systematically examined. RESULTS: Whilst there was a relatively weak relationship between the supply factors that were measured, there did not appear to be any reciprocal relationship. Three parsimonious models estimated using ordinary least squares multiple regression techniques based on combinations of permanent sickness, low birth weight and the proportion of general practitioners registered for postgraduate certificate of education were identified. The models explained up to 61% of variation between districts in prescribing costs. CONCLUSIONS: 'Need' and 'supply' characteristics are independently associated with variations in prescribing costs at district level. The negative association between the proportion of general practitioners eligible for postgraduate education allowance and prescribing costs may reflect 'better' prescribing but could not be introduced into a resource allocation formula without introducing perverse incentives. The combination of permanent sickness and low birth weight complement each other by providing a proxy measure of morbidity mostly applicable to adult males (permanent sickness) and mothers (low birth weight being a measure of maternal health). These variables should be considered further for use in the process of allocating resources for prescribing to districts.

Cost Allocation↗
PubMed1996

Socioeconomic determinants of rates of consultation in general practice based on fourth national morbidity survey of general practices.

OBJECTIVE: To identify the socioeconomic determinants of consultation rates in general practice. DESIGN: Analysis of data from the fourth national morbidity survey of general practices (MSGP4) including sociodemographic details of individual patients and small area statistics from the 1991 census. Multilevel modelling techniques were used to take account of both individual patient data and small area statistics to relate socioeconomic and health status factors directly to a measure of general practitioner workload. RESULTS: Higher rates of consultations were found in patients who were classified as permanently sick, unemployed (especially those who became unemployed during the study year), living in rented accommodation, from the Indian subcontinent, living with a spouse or partner (women only), children living with two parents (girls only), and living in urban areas, especially those living relatively near the practice. When characteristics of individual patients are known and controlled for the role of "indices of deprivation" is considerably reduced. The effect of individual sociodemographic characteristics were shown to vary between different areas. CONCLUSIONS: Demographic and socioeconomic factors can act as powerful predictors of consultation patterns. Though it will always be necessary to retain some local planning discretion, the sets of coefficients estimated for individual level factors, area level characteristics, and for practice groupings may be sufficient to provide an indicative level of demand for general medical services. Although the problems in using socioeconomic data from individual patients would be substantial, these results are relevant to the development of a resource allocation formula for general practice.

Adolescent↗