Procalcitonin in systemic and localized bacterial infection

Introduction: Procalcitonin (PCT) has been proposed as a marker of infection in critically ill patients. The aim of the study was to evaluate and compare the possible discriminative use of PCT together with other standard inflammatory parameters, such as C-reactive protein (CRP), platelets (PLT), white blood cell count (WBC) and immature granulocytes (IG) in differentiating systemic and localized bacterial infection in critically ill patients. Materials and methods: According to clinical sings and microbiologic findings, 25 patients were divided into two groups: group A - patients with systemic bacterial infection and group B - patients with localized bacterial infection. Concentration of PCT and CRP; PLT, WBC and IG count were determined in all patients. Results: The median concentration of PCT was 1.3 (range: 0.1-7.4) μg/L in group A and 0.2 (range: 0.1-9.1) μg/L in group B with differences between groups being statistically significant (P = 0.038). A significantly higher median PLT count (P = 0.012) was found in group B (327, range: 91-647 x 109/L) as compared to group A (140, range: 40-325 x 109/L). In contrast, there were no statistically significant differences in median values of CRP, WBC and IG between groups (P = 0.071; 0.189 and 0.239, respectively). According to ROC (receiver operating characteristic) analysis, the obtained cut-off value for PCT as the marker of systemic bacterial infection was 0.3 μg/L (sensitivity 91%, specificity 64%). Conclusion: According to our results, PCT concentrations and PLT counts showed better discrimination than other investigated standard inflammatory parameters for differentiating systemic from localized bacterial infection in critically ill patients

Effect of cold agglutinins on red blood cell parameters in a trauma patient: a case report

The presence of cold agglutinins (CAs) in samples intended for complete blood count (CBC) using automated haematology analysers might cause serious preanalytical errors. In this report we describe the case of a 90-year old female patient admitted to the Emergency department following trauma injuries. A blood testing on admission revealed surprisingly low red blood cell count (0.99 x 1012/L), low haematocrit (0.102 L/L) which did not correlate with haemoglobin concentration (100 g/L), and high erythrocytes indices (mean corpuscular haemoglobin, 101 pg; mean corpuscular haemoglobin concentration, 980 g/L). In the second sample, after repeated collection, almost equal results were observed. Blood smear examination under the microscope revealed clusters of erythrocytes. Cold agglutinins presence was suspected and, in order to get valid results, sample was warmed to 37 °C. Correction of CBC was observed. Furthermore, we performed some additional analysis to confirm the presence of CAs in this patient. The aim of this report was to present the laboratory findings in a case of CAs and propose a laboratory procedure for whole blood samples with suspected CAs

Nucleation and crystal growth of zeolite A synthesised from hydrogels of different density

International audienceVarious factors affect the process of zeolite formation and thus the characteristics of the ultimate material. The present study is devoted to the influence of the density of the starting aluminosilicate hydrogels, i.e. the amount of the solid phase in the system, on the characteristics of the final product. Different density (viscosity) of the five alumosiliate gels was obtained by changing the ratio SiO2/H2O, while the ratios Na2O/H2O and SiO2/Al2O3 remained constant. The freshly prepared hydrogels were hydrothermally treated at 80 degrees C under static conditions. The reaction course was followed by a set of complementary analyses including XRD, chemical analysis, microscopy and thermogravimetry. The linear rate of crystal growth was calculated according to Zhdanov and Samulevich's method. The crystal size distribution curves of the end products were measured and the corresponding curves of nuclei distribution within gel matrix and specific number of crystals were calculated. The observed effect of “local ordered structure” (potential nuclei) formation was commented on from the viewpoint of the autocatalytic nucleation theory

Influence of alkalinity of the starting system on size and morphology of the zeolite A crystals

International audienceThe performance of zeolite crystals in different industrial processes often depends on their size and shape. Several physico-chemical parameters can have significant impact on their particulate properties (especially morphology). Amongst the chemical parameters the Si/Al ratio is one of most important variable together with the Na+ ions (alkalinity) content. The present study is devoted to the effect of Na on the morphology of zeolite A (LTA-type) crystals. Initial hydrogels were heated at 80 degrees C in reactors made of HDPE, under static conditions. After separation by centrifugation, samples of solid and liquid phase were characterized using several analytical methods such as: atomic absorption spectroscopy, Xray diffraction, laser light scattering, optical, scanning and transmission electron microscopy. The results show that the increase of alkalinity in starting system causes two effects: (a) increase of the number of nuclei (crystals) in system through additional nucleation at surface and subsurface area of gel particles, and (b) the growth of crystals which have more irregular shape (rounded edges). (C) 2011 Elsevier B.V. All rights reserved

Influence of alkalinity of the starting system on size and morphology of the zeolite A crystals

International audienceThe performance of zeolite crystals in different industrial processes often depends on their size and shape. Several physico-chemical parameters can have significant impact on their particulate properties (especially morphology). Amongst the chemical parameters the Si/Al ratio is one of most important variable together with the Na+ ions (alkalinity) content. The present study is devoted to the effect of Na on the morphology of zeolite A (LTA-type) crystals. Initial hydrogels were heated at 80 degrees C in reactors made of HDPE, under static conditions. After separation by centrifugation, samples of solid and liquid phase were characterized using several analytical methods such as: atomic absorption spectroscopy, Xray diffraction, laser light scattering, optical, scanning and transmission electron microscopy. The results show that the increase of alkalinity in starting system causes two effects: (a) increase of the number of nuclei (crystals) in system through additional nucleation at surface and subsurface area of gel particles, and (b) the growth of crystals which have more irregular shape (rounded edges). (C) 2011 Elsevier B.V. All rights reserved