Stability of complete blood count in different storage conditions using the ABX PENTRA 60 analyzer

INTRODUCTION

Sample stability is essential to obtain reliable results in the clinical laboratory. This study was conducted to investigate the reliability of hematological parameters using ABX Pentra 60 in samples stored for up to 72 hours at different temperatures.

METHODS

A total of 651 blood samples were analyzed at different analysis times: 2, 24, 48, and 72 hours and forms and storage: room temperature (25°C) and at 4°C. The imprecision of the results was evaluated by the analytical coefficient of variation (CVa%) obtained by the typical error (TE) and Kruskal-Wallis analysis, to compare the averages. The reliability of the results was evaluated by the CVa (%) within the maximum allowable analytical variation and by the difference of means of the results in relation to the baseline sample (2 hours).

RESULTS

Red blood count, hemoglobin, and MCH parameters showed stability up to 72 hours at room temperature and at 4°C. The other complete blood count parameters showed imprecision results emitted by the ABX Pentra 60 from 24 hours of sample storage, independent of the storage temperature. In addition, there were significant oscillations in the mean values, particularly for the samples stored at room temperature, with the exception of platelet parameters that exhibited mean changes also at 4°C.

CONCLUSION

The results demonstrate the importance of the clinical analyst's knowledge about the behavior of the CBC parameters over time under different storage conditions, and mainly the imprecision of the hematological equipment used, for the suitable interpretation of the results.

Pravastatin induces cell cycle arrest and decreased production of VEGF and bFGF in multiple myeloma cell line

Multiple myeloma (MM) is a B cell bone marrow neoplasia characterized by inflammation with an intense secretion of growth factors that promote tumor growth, cell survival, migration and invasion. The aim of this study was to evaluate the effects of pravastatin, a drug used to reduce cholesterol, in a MM cell line.Cell cycle and viability were determinate by Trypan Blue and Propidium Iodide. IL6, VEGF, bFGF and TGFβ were quantified by ELISA and qRT-PCR including here de HMG CoA reductase. It was observed reduction of cell viability, increase of cells in G0/G1 phase of the cell cycle and reducing the factors VEGF and bFGF without influence on 3-Methyl-Glutaryl Coenzyme A reductase expression.The results demonstrated that pravastatin induces cell cycle arrest in G0/G1 and decreased production of growth factors in Multiple Myeloma cell line.

Experience with a cross-study endpoint review committee for AIDS clinical trials. Terry Beirn Community Programs for Clinical Research on AIDS

OBJECTIVES

To describe the methods and results of a standardized system for clinical endpoint determination for defining and reviewing endpoints in clinical trials for HIV-infected individuals.

DESIGN

A system was developed utilizing standard definitions for the 24 diagnoses or clinical events that serve as trial endpoints and together define the combined endpoint 'progression of HIV disease. A common set of case report forms were used for all trials. Thus, an event of Pneumocystis carinii pneumonia (PCP), for example, for a subject co-enrolled in an antiretroviral trial and a PCP prophylaxis trial was only reported once.

METHODS

A central committee was established to define clinical events and review endpoints across all studies. Events were classified according to established criteria for confirmed, probable and possible levels of certainty.

RESULTS

This report describes the methods used to ascertain and review endpoints, and summarized 2299 clinical events for 8097 subjects enrolled in one or more of nine clinical trials. Data on the diagnostic certainty of events and agreement between site clinicians and the endpoint committee are presented.

CONCLUSIONS

Uniform classification of endpoints across AIDS clinical trials can be accomplished by multicenter, multitrial organizations with standardized definitions and review of endpoint documentation. Our experience suggests that nurse coordinators reviewing all submitted endpoints for every trial are warranted and the need for external review by a clinical events committee may depend on the type of trial conducted.