Reliability of the cloned-enzyme donor immunoassay (CEDIA) for cocaine in human serum in the range between the detection limit and the cut-off

Immunoassays are used worldwide for the rapid screening of drugs. Despite the fact that they are highly valuable tools for the testing of legal and illicit drugs, there is a non-negligable risk of false-positive and false-negative findings and many pitfalls must be taken into account when using these tests in an uncritical manner and without valid confirmation procedures. In order to check the correlation between cloned-enzyme donor immunoassay (CEDIA) readings and exact determined gas chromatography/mass spectrometry (GC/MS) values for benzoylecgonine, a total of 472 serum samples was measured with an immunoassay (CEDIA) as well as GC/MS. As a result, it was shown that in the lower area of concentration, up to approx. 300 ng equ. benzoylecgonine/ml, there is a semiquantitative useful correlation. With higher concentrations, the values shift more and more apart and many runaways are visible. Generally the use of tests for materials other than those declared is excluded from the manufacturer's warranty and is at the user's own risk, but the authors found that many immunochemical tests with a certification only for the use in urine are well suited to the screening of serum samples, and even low readings could be confirmed by GC/MS. With blood or serum as sample, it could be regularly observed that generally very small readings could not only be confirmed with mass spectrometry but could in most cases also be quantified. This was the key factor in determining the rate of confirmation in 495 cases. In total, an incredibly high reliability for the CEDIA cocaine test (via benzoylecgonine) was shown up to the area of detection (detection limit), far below the cut-off. These results confirm the extraordinary sensitivity and specificity of this test also for blood or serum as sample material to be tested.     

Adaptive decision-making: how Australian healthcare managers decide

Despite many calls for the utilisation of research evidence in health policy-making, it is not widely practised, and little is known about how decision-makers in healthcare organisations actually make decisions. We recruited a purposive sample of Australian healthcare decision-makers to complete a web-based survey. We then took a sub-sample from willing respondents for individual interviews. All interviews were audio-recorded, transcribed verbatim and coded thematically. We found that resource allocation decision-making varied greatly across the Australian healthcare system. Decision-making was highly dependent on the operational context in time, place and purpose, and that research evidence was rarely exploited to its full potential. Decision-making involved a multifaceted interplay of elements in situation of inquiry. All decisions were made by networks or collectives of people; and no instance of individual decision-making was reported. This varied, social and contextual nature of decision-making points to a complexity that is not reflected in systematic evidence-based reviews or evidence-based models for decision-making, and we did not discover an appropriate model to reflect this complexity in the health- related literature. We developed a model of 'adaptive decision-making' that has potential to guide robust decision-making in complex situations, and could have some value as an explanatory or theoretical model for teaching and practice.     

Studies of interferences of apomorphine and its metabolites or decomposition products with immunochemical screening tests for legal and illicit drugs after therapeutic doses of apomorphine

This study deals with the question of whether apomorphine (CAS 314-19-2; e.g. in Ixense) and its metabolites or decomposition products interfere with the specificity of immunochemical screening tests (immunoassays) for legal and illicit drugs. It was the result of the investigations that after the therapeutic use of apomorphine no relevant false-positive screening findings were observed with the CEDIA (cloned enzyme donor immuno assay) and FPIA (fluorescence polarisation immuno assay) tests, which are commonly encountered in drug-screening programs, when using recommended cut-off values for urine.     

Factors associated with participation in resident action groups in metropolitan Sydney: a cross-sectional survey

OBJECTIVE: To explore the characteristics of participants in resident action groups in metropolitan Sydney. METHODS: A stratified random sample of participants in 50 groups registered with local councils were surveyed in 1997. Demographic, social/psychological, cost/benefit, group process and group potency variables and four measures of amount of participation were examined. RESULTS: An increase in the hours of participation per month was associated with a decrease in the self-reported costs of participation, an increase in the self-reported benefits of participation and an increase in group potency. Involvement in a greater number of activities was associated with a decrease in the self-reported costs and an increase in the self-reported benefits associated with participation, increased satisfaction with group processes, a decrease in group potency and an increase in the number of members known prior to group membership. Length of group membership was positively associated with age and more positive expectations of the group's future success. An increase in the proportion of meetings attended was associated with self-reported satisfaction with group processes. CONCLUSIONS AND IMPLICATIONS: An important principle of public health is community participation. The results of this study indicate that the greatest potential for increasing individual participation may be in efforts to reduce the costs associated with participation, increase the benefits associated with participation and increase the satisfaction of group members with group processes.     

Is 8860 variation a rare polymorphism or associated as a secondary effect in HCM disease?

Introduction

mtDNA defects, both deletions and point mutations, have been associated with hypertrophic cardiomyopathies. The aim of this study was to establish a spectrum for mtDNA mutations in Iranian hypertrophic cardiomyopathy (HCM) patients.

Material and methods

The control group was chosen among the special medical centre visitors who did not have hypertrophic cardiomyopathy or any related heart disease. Hypertrophic cardiomyopathy (HCM) is widely accepted as a pluricausal or multifactorial disease. Because of the linkage between energy metabolism in the mitochondria and cardiac muscle contraction, it is reasonable to assume that mitochondrial abnormalities may be responsible for some forms of HCM. Point mutations and deletions in the two hot spot regions of mtDNA were investigated by PCR and sequencing methods.

Results

Some unreported point mutations have been found in this study but no deletion was detected. Meanwhile some of these point mutations have been investigated among HCM patients for the first time.

Conclusions

A8860G transition was detected in a high proportion, raising the question whether this rare polymorphism is associated as a secondary effect in HCM disease.     

Pitfalls of toxicological analysis

Pitfalls are a permanent risk in all fields of forensic- and clinical-toxicological analysis and are not only concerned with immunoassays, although they are at present mostly discussed with regard to this subject. There are risks inherent in the field of preanalysis (e.g. the sampling, transportation, storage und treatment of the samples immediately prior to analysis). Furthermore, various pitfalls during measurement itself are to be avoided in connection with derivatization, choice of analysis parameters, memory-effects and many other sources of error. Another important section concerns the pharmacokinetic and pharmacodynamic interpretation of analytical results. Many toxicokinetic (e.g. enzyme induction) and toxicodynamic factors (e.g. tolerance effects) must be considered with special regard to plausibility controls (e.g. constellation, longitudinal, transversal and trend monitoring).     

Schools as social complex adaptive systems: A new way to understand the challenges of introducing the health promoting schools concept

Achieving system-wide implementation of health promotion programs in schools and sustaining both the program and its health related benefits have proved challenging. This paper reports on a qualitative study examining the implementation of health promoting schools programs in primary schools in Sydney, Australia. It draw upon insights from systems science to examine the relevance and usefulness of the concept of “complex adaptive systems” as a framework to better understand ways in which health promoting school interventions could be introduced and sustained. The primary data for the study were collected by semi-structured interviews with 26 school principals and teachers. Additional information was extracted from publicly available school management plans and annual reports. We examined the data from these sources to determine whether schools exhibit characteristics of complex adaptive systems. The results confirmed that schools do exhibit most, but not all of the characteristics of social complex adaptive systems, and exhibit significant differences with artificial and natural systems. Understanding schools as social complex adaptive systems may help to explain some of the challenges of introducing and sustaining change in schools. These insights may, in turn, lead us to adopt more sophisticated approaches to the diffusion of new programs in school systems that account for the diverse, complex and context specific nature of individual school systems.     

Immunoassays for drug screening in urine

Immunoassays are presently used worldwide for the rapid screening of drugs. Despite the fact that they are a highly valuable tool for the testing of legal and illicit drugs, there is a real risk of false-positive and false-negative findings and many pitfalls must be taken into account when these tests are used in an uncritical manner and without valid confirmation procedures. In a long-standing successful cooperation with a large psychiatric hospital, we checked doubtful and nonplausible immunochemical findings in urine with gas chromatography-mass spectrometry (GC-MS) confirmation methods. The reported case histories demonstrate typical pitfalls, for example, influence of changing nutritional habits, use of sweeteners (cyclamate), uncritical creatinine correction, impaired elimination, or cross-reactivities of simultaneous therapeutic medication. In accordance with national and international associations, immunoassays are recommended as a useful tool for screening. However, confirmation analysis with conclusive methods (GC-MS or liquid chromatography-MS) is unavoidable for valid substance identification, discrimination between active and inactive metabolites, detection of congeners, and accurate determination of concentrations in body fluids.