Standard reference materials and data quality assurance in the biomedical analysis of trace elements

Accurate and precise analytical data of the concentrations of bioanalytes in bioclinical studies are of fundamental importance. Quality assurance procedures should always be performed to check the overall analytical work. This can be conveniently performed if appropriate standard reference materials with known concentrations of the analyte object of study are available. This paper underlines the key points related to the production and use of biological standard materials for trace element analysis. In particular, the present situation in the field of trace element determination in human biological fluids and the related problems are illustrated. The considerations given in this work may contribute to the preparation of the new biomarker standard materials.     

Effects of pertussis toxin and indomethacin on murine lymphocytes in the bronchoalveolar lavage fluids

The total number of lymphocytes in the bronchoalveolar lavage (BAL) fluids significantly increased in mice injected intravenously with pertussis toxin (PT), while the absolute number of alveolar macrophages markedly decreased. This finding probably reflects the lymphocyte accumulation in interstitial spaces as we previously observed in mice injected with PT. In addition, indomethacin, at lower dosage (0.5 mg/kg) prevented peripheral lymphocytosis and lymphocyte accumulation in the alveolar spaces of the lungs of mice injected with PT. These results provide evidence that PT is responsible for lymphocyte accumulation together with a marked decrease of alveolar macrophages in the lungs of treated mice; moreover, indomethacin is effective in preventing bronchoalveolar changes caused by PT.     

Pretreatment of outer membrane vesicle and subsequent infection with influenza virus induces a long-lasting adaptive immune response against broad subtypes of influenza virus

Influenza is an acute respiratory disease and a global health problem. Although influenza vaccines are commercially available, frequent antigenic changes in hemagglutinin might render them less effective or unavailable. We previously reported that modified outer membrane vesicle (fmOMV) provided immediate and robust protective immunity against various subtypes of influenza virus. However, the effect was transient because it was innate immunity-dependent. In this study, we investigated the effects of consecutive administration of fmOMV and influenza virus on the adaptive immune response and long-term protective immunity against influenza virus. When the mice were pretreated with fmOMV and subsequently infected with influenza virus, strong influenza-specific antibody and T cell responses were induced in both systemic and lung mucosal compartments without pathogenic symptoms. Upon the secondary viral challenge at week 4, the mice given fmOMV and influenza virus exhibited almost complete protection against homologous and heterologous viral challenge. More importantly, this strong protective immunity lasted up to 18 weeks after the first infection. These results show that pretreatment with fmOMV and subsequent infection with influenza virus efficiently induces broad and long-lasting protective immunity against various virus subtypes, suggesting a novel antiviral strategy against newly-emerging viral diseases without suitable vaccines or therapeutics.     

Evaluation of the potential of biodegradation for the disposal of cutting fluid from the machining of uranium

The disposal of used cutting fluid from the machining of uranium is problematical. Biodegradation offers the potential to convert this material into forms amenable to disposal as low level radioactive waste. The real bonus of biodegradation for radioactive applications crucially depends on the degree of mineralisation achieved. In non-radioactive trials using a consortium of bacteria selected from used cutting fluid, only 33% of the organic carbon was converted to carbon dioxide, even though 90% of the principal component (hydrocarbons) was biodegraded. Intermediate degradation products (identified as naphthenic acids) accumulated. Downstream processing of the biotreated fluid by ultrafiltration and adsorption onto activated charcoal produced a waste stream that would qualify as aqueous radioactive waste. Separated biomass was immobilised in a cement matrix that would qualify as solid radioactive waste, albeit in a volume which would make the overall process inefficient. Future work to optimise the process is proposed.     

A Screening Analysis of the High‐Pressure Extraction of Anthocyanins from Red Grape Pomace with Carbon Dioxide and Cosolvent

In the work described here, a set of screening factorial design experiments was carried out in order to study the extraction process of anthocyanins from red grape pomace with carbon dioxide, along with either methanol or water as cosolvent, at high pressure. The variables studied were pressure, temperature, solvent flow‐rate, cosolvent percentage, cosolvent type (methanol or water) and extraction time. The quantification of the total amount of anthocyanins was performed by a colorimetric method. The results of the ANOVA study show a strong influence of the type and percentage of cosolvent. The best results were obtained with 20 mol‐% of methanol, 100 bar, 60 °C and a flow‐rate of 22 mmol/min after two hours of extraction.     

Micronization of Organic Materials by Crystallization with Compressed Gases

A pilot plant is presented, which has been built to prepare fine particles by the P recipitation with a C ompressed Fluid A ntisolvent (PCA process). This technique offers interesting applications for products, which are produced in small amounts, as certain pharmaceuticals or energetic materials. In this contribution the micronization of paracetamol and tartaric acid is presented. Liquid solutions of tartaric acid in acetone, ethanol and methanol/ethanol mixtures have been sprayed into supercritical carbon dioxide used as antisolvent. The mean particle size of the precipitated powder can be manipulated by changing the precipitation pressure and solvent type however the precipitation temperature has no significant influence on the particle size. Paracetamol is micronized from acetone, methanol and DMF and morphologies from needles to spheres were found depending on the solvent. The particle size was in the submicron range.