The effect of extremely high glucose concentrations on 21 routine chemistry and thyroid Abbott assays: interference study

Introduction

Extremely high glucose concentrations have been shown to interfere with creatinine assays especially with Jaffe method in peritoneal dialysate. Because diabetes is the fastest growing chronic disease in the world, laboratories study with varying glucose concentrations. We investigated whether different levels of glucose spiked in serum interfere with 21 routine chemistry and thyroid assays at glucose concentrations between 17-51 mmol/L.

Materials and methods

Baseline (group I) serum pool with glucose concentration of 5.55 (5.44-5.61) mmol/L was prepared from patient sera. Spiking with 20% dextrose solution, sample groups were obtained with glucose concentrations: 17.09, 34.52, and 50.95 mmol/L (group II, III, IV, respectively). Total of 21 biochemistry analytes and thyroid tests were studied on Abbott c8000 and i2000sr with commercial reagents. Bias from baseline value was checked statistically and clinically.

Results

Creatinine increased significantly by 8.74%, 31.66%, 55.31% at groups II, III, IV, respectively with P values of < 0.001. At the median glucose concentration of 50.95 mmol/L, calcium, albumin, chloride and FT4 biased significantly clinically (-0.85%, 1.63%, 0.65%, 7.4% with P values 0.138, 0.214, 0.004, < 0.001, respectively). Remaining assays were free of interference.

Conclusion

Among the numerous biochemical parameters studied, only a few parameters are affected by dramatically increased glucose concentration. The creatinine measurements obtained in human sera with the Jaffe alkaline method at high glucose concentrations should be interpreted with caution. Other tests that were affected with extremely high glucose concentrations were calcium, albumin, chloride and FT4, hence results should be taken into consideration in patients with poor diabetic control.Key words: assay interference, glucose interference, preanalytical phase, creatinine, Jaffe kinetic assay, thyroid function tests     

Museums,schools and geographies of cultural value

This article explores a paradox and a possibility that have emerged from two pieces of policy-related research concerning educational use of museums within England. The paradox relates to the use of museums which, whilst widely perceived as rather elitist institutions, appear from a postcode analysis of school visits to museums to be visited by large numbers of schools located in areas of social deprivation. The present analysis further explores this paradox, drawing on revised postcode analysis and governmental indices of multiple deprivation and income deprivation affecting children. The analysis supports the contention that museums attracted visits from schools located in areas with some of the highest levels of deprivation, although it suggests that this result needs to be considered in relation to regional differences in areas of social deprivation, the location of museums and the differences between individual and area-based measures of deprivation. Attention is then drawn to the potential of considering museums through a geographical perspective, and specifically through Foucault's notions of primary, secondary and tertiary spatializations. It is argued that primary spatializations encompasses how museums are conceptualized and classified; secondary spatializations concern how various elements of museums are articulated together; and tertiary spatializations relate to the placement of museums in wider societal contexts and processes. It is suggested that the postcode analysis of school visits points both to the significance of considering tertiary spatializations relating to the social circumstances of museum visitors but also raised questions concerning primary spatializations of museums. Attention is drawn to changes in the classification and grouping of museums, and how these often encompass geographically based criteria related to the social reach of museums. The article ends by considering the degree to which museums might seek to further change their primary spatialization to reflect tertiary spatializations relating to cultural value.     

IPv6: The next generation Internet Protocol

IPv4, the workhorse protocol of the currently popular TCP/ IP protocol suite, is fast becoming obsolete. The exponential growth of the Internet is the main reason that has required the creation of the next generation of Internet Protocol-IPv6. IPv6 is much more flexible and promises to take care of the address space and security issues in the foreseeable future. Part 1 of the paper lays the foundation of the various issues involved in designing the Internet Protocol and motivates the need for an upgraded version of this protocol.     

On the role of cultural participation in tourism destination performance: an assessment using robust conditional efficiency approach

The relationship between culture and tourism has been widely investigated from different perspectives. A large strand of literature studies the role of cultural heritage to attract tourists, while a rich bulk of studies on cultural participation investigates the impact of tourism flows on the demand for culture. Another aspect worth investigating relates to the link between cultural participation and the performance of tourism destinations (TDs), as a higher cultural participation in an area could boost the performance in the management of tourism resources. However, so far, this issue has been disregarded in the literature, and this paper aims at filling this gap. Specifically, it studies the effect of cultural participation on TDs’ performance using a conditional efficiency approach that ensures robust inference on the role of environmental factors. We employ data on the Italian regions for the period 2004–2010, and we explore the role of cultural participation for tourism by using several indicators. Our findings offer empirical support to the positive role of cultural participation and, thus, suggest that public cultural policies might also boost the efficiency of the tourism sector.     

Pore structure of historic and repair Roman cement mortars to establish their compatibility

Mercury porosimetry was applied to the study of pore structure of the historic Roman cement mortars representative of different locations in Europe and time periods as well as different application techniques from architectural castings to in situ formed renders and profiles. Three categories of pores were found to coexist in the mortars. The finest pores, with diameters below 0.1 μm, are present within the hardened aged Roman cement matrix. The larger ‘air’ pores, with diameters between 0.2–2 μm, are due to the evaporation of the excess unbound water and restricted hydration. Pores larger than 2 μm are rare and, in general, can be related to microcracking induced by shrinkage drying and mortar weathering. The mortars have rarely been found to develop a dense fine-porous microstructure characteristic of the ideal conditions of moist-curing; massive architectural castings being the only exception identified. The presence of larger ‘air’ pores was, in turn, almost universally observed. The investigations of the freshly prepared Roman cement mortars have revealed that the restricted hydration could be due to the exposure of the freshly laid surface to dry real-world external environments, a high water-to-cement ratio in the original mortars, or the drawing of water from the stucco mass due to insufficient pre-wetting of the porous masonry. The insufficient reactivity of historic cements, resulting from a high content of over-burned, non-reactive cement components or coarseness of the cement grains, could be another reason for yielding poorly hydrated mortars in the past. In general, Roman cement stuccoes are in an excellent state of preservation in spite of their usual exposure to polluted urban environments for more than a century. Therefore, the coexistence of Roman cement mortars of widely different pore structures has not brought about any problems of incompatibility which field observations could reveal. The Roman cement repair materials have been found to develop pore structures similar to those of historic mortars. Therefore, they are in broad terms compatible with historic masonry or stuccoes. However, the porosity and strength of the repair materials can be controlled by a careful manipulation of the water-to-cement ratio of the mix to adapt them better to the properties of the host material.     

Practical Applications as a Source of Credibility: A Comparison of Three Fields of Dutch Academic Chemistry

In many Western science systems, funding structures increasingly stimulate academic research to contribute to practical applications, but at the same time the rise of bibliometric performance assessments have strengthened the pressure on academics to conduct excellent basic research that can be published in scholarly literature. We analyze the interplay between these two developments in a set of three case studies of fields of chemistry in the Netherlands. First, we describe how the conditions under which academic chemists work have changed since 1975. Second, we investigate whether practical applications have become a source of credibility for individual researchers. Indeed, this turns out to be the case in catalysis, where connecting with industrial applications helps in many steps of the credibility cycle. Practical applications yield much less credibility in environmental chemistry, where application-oriented research agendas help to acquire funding, but not to publish prestigious papers or to earn peer recognition. In biochemistry practical applications hardly help in gaining credibility, as this field is still strongly oriented at fundamental questions. The differences between the fields can be explained by the presence or absence of powerful upstream end-users, who can afford to invest in academic research with promising long term benefits.