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The oxidative potential (OP) of the gas phase is an important and neglected aspect of environmental toxicity. Whilst prolonged exposure to particulate matter (PM) associated reactive oxygen species (ROS) have been shown to lead to negative health effects, the potential for compounds in gas phase to cause similar effects is yet to be understood. In this study we describe: the significance of the gas phase OP generated through vehicle emissions; discuss the origin and evolution of species contributing to measured OP; and report on the impact of gas phase OP on human lung cells. The model aerosol for this study was exhaust emitted from a Euro III Common-rail diesel engine fuelled with different blends of diesel and biodiesel. The gas phase of these emissions was found to be potentially as hazardous as the particle phase. Fuel oxygen content was found to negatively correlate with the gas phase OP, and positively correlate with particle phase OP. This signifies a complex interaction between reactive species present in gas and particle phase. Furthermore, this interaction has an overarching effect on the OP of both particle and gas phase, and therefore the toxicity of combustion emissions.

Item does not contain fulltext The biochemical characterization of antigen degradation is an important basis for a better understanding of both the immune response and autoimmune diseases mediated by MHC class II molecules. In this study we used high-performance liquid chromatography and mass spectrometry to analyze the processing of myelin basic protein (MBP), a potential autoantigen implicated in the pathogenesis of multiple sclerosis. We resolved the kinetics of MBP processing by lysosomal extracts or purified endocytic proteases, identified the major cleavage sites during this process and assigned them to the activity of proteolytic enzymes. Proteolytic processing of MBP is mostly guided along the hydrophobic regions of the protein. It is initiated by two proteolytic steps (after N(92) and S(110)) that are performed by an asparagine-specific endopeptidase (AEP) and by cathepsin (Cat) S, respectively. The resulting processing intermediates are converted into more than 60 different species of 20-40-mers due to the activity of endopeptidases including CatS, D and L. The fragments thus generated are subsequently degraded by C- or N-terminal trimming. Strikingly, the initial cleavages during MBP processing affect two immunodominant regions of the potential autoantigen [MBP(85-99) and MBP(111-129)] in an inverse manner. CatS directly generates the N terminus of the epitope MBP(111-129) in large quantities during the initial phase of processing, which might explain the immunogenicity of this region in spite of its relatively poor binding to HLA-DR4. In contrast, the dominant cleavage by AEP mediates the destruction of MBP(85-99) unless the epitope is protected, e.g. by binding to HLA-DR. Our results thus characterize the proteolytic events during processing of MBP on a molecular level and suggest a biochemical basis for the immunogenicity of the immunodominant epitopes, which could serve as a guideline for future therapeutic strategies.

Two siblings with a peptide TAP deficiency were recently described. Despite poor cell surface expression of HLA class I molecules, these patients were not unusually susceptible to viral infections. The majority of the cell surface-expressed class I molecules were HLA-B products as assessed by cytofluorometry and biochemical analysis. Analysis of two peptides eluted from the class I molecules expressed by TAP-deficient EBV B lymphoblastoid cell lines indicated that both were derived from cytosolic proteins and presented by HLA-B molecules. Peripheral alphabeta CD8+ T cells were present and their TCR repertoire was polyclonal. Most of the alphabeta CD8+ T cell clones studied (21 of 22) were nonreactive against cells expressing normal levels of the same HLA alleles as those of the TAP-deficient patients. However, it was possible to isolate one cytotoxic CD8+ alphabeta T cell clone recognizing the EBV protein LMP2 presented by HLA-B molecules on TAP-deficient cells. These observations suggest that in the TAP-deficient patients, CD8+ alphabeta T cells could mature and be recruited in immune responses to mediate HLA class I-restricted cytotoxic defense against viral infections. They also strengthen the physiologic importance of a TAP-independent processing pathway of the LMP2 protein, which was previously shown to contain several other TAP-independent epitopes.

Brain: A Journal of Neurology, 136 (6), ISSN:0006-8950, ISSN:1460-2156

Tailor made bioceramic scaffolds in combination with the corresponding surface chemistry and biology is of great importance for a successful implantation and rapid osseo-integration. The present study investigates the fabrication of Hydroxyapatite (HA) scaffolds with defined macro porosity by means of powder based 3D-printing. In order to mime natural bone with its elastic collagen structure, the 3D-printed ceramic structures were post-treated by polymeric infiltration. Compressive Strength analysis (CS) confirmed the positive impact of an elastomeric phase on mechanical properties. 3D-printed HA scaffolds in combination with polymer result in biodegradable scaffolds with promising mechanical properties for potential use in regenerative medicine.

In this paper, a robust output tracking controller for quadrotor helicopter is proposed. The proposed controller requires measurement of only four state variables: positions in inertial coordinate frame and yaw angle. Also, the controller is robust to unmodeled dynamics and provides rejections of all external force and torque disturbances. The effectiveness of the proposed controller is tested on a simulation example of quadrotor tracking under wind influence which is modeled as unmatched external force disturbances in horizontal plane.

The paper analyzes the impact of scientific and technological progress on the environment and the impact of biotechnology and eco – technology in agricultural development strategy, based on the rational use of natural resources. The key problem in the application of technological developments in agriculture is based on creating the optimal interdependence of the development of the biotechnology and of eco - technology on one hand and optimal use of natural agricultural resources from the other. Special emphasis is placed on the development of "friendly" technologies that have a positive impact on the ecology and the escalation of development and economic opportunities. On this basis, the sustainable development of agriculture is an essential foundation for achieving and directing the production of biologically valuable and quality agricultural products.

This paper contains a regional-comparative analysis of some of the most important indicators of the world production and international trading in fruit, as extremely significant in the diet and indispensable food product group. It specially analyses trends, concerning regional differences in the volume, dynamics and structure of production and trade of apples, plums, cherries and sour cherries, strawberries, raspberries and grapes. Regions, i.e. countries, the largest producers and largest exporters and importers of these products have been defined. Subsequently, it was found that there are very significant regional differences which is the consequence of numerous natural, economic and social factors. In the analysis of character of relations and the degree of influence of aformentioned factors on changes and development directions of the observed phenomenon, quantitative and qualitative market research methods were used.

Main precondition for a country to achieve economic growth is to be included in integration processes. It is no longer question is it or is it not necessary to have global/regional connections, but how to make existing relations more efficient, fair and useful for all participants. EU is an example how, in relatively short period, good environment for economic growth and increase of democratic standards in new country members can be created. Outspreading of EU tension between developed West and undeveloped East Europe are diminished. EU gives good example for others in different areas. Serbian economy during 1990’s was characterised by low investment, technicaltechnological lag and stagnation of growth. Today’s GDP of Republic of Serbia is 65% of GDP from 1990. However, new EU members have already compensation transitional falls and readjust their structure of economy to EU demands. Decreasing and stagnation of GDP in Republic of Serbia on the beginning of transitional process were stopped after 2000 and returned to stable and dynamic trends of growth. However, Republic of Serbia needs to perform significant changes in economic structure and to maintain on long term high growth rate, reduce inflation and unemployment. That will contribute to further growth of GDP per capita and bring Serbia closer to level of development of other EU countries.

Prothymosin alpha (ProTα) is an acidic polypeptide associated both with cell proliferation and immune regulation. Although ProTα's immunomodulating activity is well established at cellular level, limited information is available regarding the signaling pathways triggered by ProTα. Using 2-DE proteomic technology, we investigated changes in protein expression of ProTα-stimulated peripheral blood mononuclear cells (PBMC) in the course of a 3-day incubation. Using healthy donor- and cancer patient-derived PBMC, 12 gels were studied, identifying 53 differing protein spots via PMF comparison analysis. Among others, we identified interleukin-1 receptor-associated kinase 4, heat-shock protein 90, lipocalin 2, ribophorin 1, eukaryotic elongation factor 2, 14-3-3 protein, L-plastin, and MX2 protein, all of which were found to be overexpressed upon ProTα activation. Based on the physiological role of upregulated proteins, we propose the following model for ProTα's immunological mode of action: on day 1, ProTα triggers monocyte activation, possibly via toll-like receptor signaling, and enhances antigen presentation, consequently promoting and stabilizing monocyte-T-cell immune synapse; on day 2, activated monocytes produce interleukin (IL)-1, while T-cell receptor triggering promotes T-cell proliferation and IL-2 production; finally, on day 3, ProTα-activated PBMC express proteins related to adhesion and cytotoxic effector functions, both contributing to the increase of their lytic activity. © 2007 Wiley-VCH Verlag GmbH & Co. KGaA.