Background: Urine is a desirable material for the diagnosis and classification of diseases because of the convenience of its collection in large amounts; however, all of the urinary proteome catalogs currently being generated have limitations in their depth and confidence of identification. Our laboratory has developed methods for the in-depth characterization of body fluids; these involve a linear ion trap-Fourier transform (LTQ-FT) and a linear ion trap-orbitrap (LTQ-Orbitrap) mass spectrometer. Here we applied these methods to the analysis of the human urinary proteome. Results: We employed one-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis and reverse phase high-performance liquid chromatography for protein separation and fractionation. Fractionated proteins were digested in-gel or in-solution, and digests were analyzed with the LTQ-FT and LTQ-Orbitrap at parts per million accuracy and with two consecutive stages of mass spectrometric fragmentation. We identified 1543 proteins in urine obtained from ten healthy donors, while essentially eliminating false-positive identifications. Surprisingly, nearly half of the annotated proteins were membrane proteins according to Gene Ontology (GO) analysis. Furthermore, extracellular, lysosomal, and plasma membrane proteins were enriched in the urine compared with all GO entries. Plasma membrane proteins are probably present in urine by secretion in exosomes. Conclusion: Our analysis provides a high-confidence set of proteins present in human urinary proteome and provides a useful reference for comparing datasets obtained using different methodologies. The urinary proteome is unexpectedly complex and may prove useful in biomarker discovery in the future.
Prion protein (PrP)Sc, the only known component of the prion, is present mostly in the brains of animals and humans affected with prion diseases. We now show that a protease-resistant PrP isoform can also be detected in the urine of hamsters, cattle, and humans suffering from transmissible spongiform encephalopathies. Most important, this PrP isoform (UPrPSc) was also found in the urine of hamsters inoculated with prions long before the appearance of clinical signs. Interestingly, intracerebrally inoculation of hamsters with UPrPSc did not cause clinical signs of prion disease even after 270 days, suggesting it differs in its pathogenic properties from brain PrPSc. We propose that the detection of UPrPSc can be used to diagnose humans and animals incubating prion diseases, as well as to increase our understanding on the metabolism of PrPScin vivo.
11 July 2008 in International Journal of Sustainability in Higher Education
Purpose: The purpose of this paper is to identify the key aspects of transformation of universities towards sustainability, such as the ideal characteristics of the “sustainable university”, and the drivers and barriers in the transformation, by comparing the strategies of seven universities world‐wide.Design/methodology/approach: A systems transformation analysis of seven case studies has been applied through a self‐evaluation based on the tridimensional Framework‐Level‐Actors (FLA) method.Findings: The study shows that none of the three dimensions of change is predominant over the others. The main barrier to be overcome is the lack of incentive structure for promoting changes at the individual level. The main drivers for change are the presence of “connectors” with society, the existence of coordination bodies and projects, and the availability of funding, all of which are important for progress. Enhancing interdisciplinarity is a strategic objective at almost all of these universities, while transformative learning is less present. A common characteristic for most of the institutions is establishing and supporting networks of expertise within the universities. These universities show important strategic efforts and initiatives that drive and nucleate change for sustainable development, the result of a combination of drivers.Practical implications: The FLA‐method has proved useful for being used at the level of comparing case‐studies through a bird's‐eye perspective.Originality/value: The paper demonstrates the application of a simple tool that gives a global perspective on transformational strategies used in seven cases world‐wide in the search for commonalities and differences.
Adipocytes are central players in energy metabolism and the obesity epidemic, yet their protein composition remains largely unexplored. We investigated the adipocyte proteome by combining high accuracy, high sensitivity protein identification technology with subcellular fractionation of nuclei, mitochondria, membrane, and cytosol of 3T3-L1 adipocytes. We identified 3,287 proteins while essentially eliminating false positives, making this one of the largest high confidence proteomes reported to date. Comprehensive bioinformatics analysis revealed that the adipocyte proteome, despite its specialized role, is very complex. Comparison with microarray data showed that the mRNA abundance of detected versus non-detected proteins differed by less than 2-fold and that proteomics covered as large a proportion of the insulin signaling pathway. We used the Endeavour gene prioritization algorithm to associate a number of factors with vesicle transport in response to insulin stimulation, a key function of adipocytes. Our data and analysis can serve as a model for cellular proteomics. The adipocyte proteome is available as supplemental material and from the Max-Planck Unified Proteome database.
The yeast estrogen screen was applied to sewage treatment process waters to identify the presence of estrogenic activity and to investigate the fate and behavior of estrogenic substances through treatment. Hydrophobic fractions in the water phase were extracted and concentrated using C18 cartridges for the effective extraction of 17β-estradiol (E2) and other estrogen mimics. Clear dose-dependent elevation in the synthesis of β-galactosidase in the yeast screen was observed with all the samples tested, demonstrating that these samples were estrogenic. However, estrogenic activity tended to reduce during the treatment, especiallyiin the biological process. Quantification results of the yeast estrogen screen in terms of E2 equivalent were compared with actual E2 concentrations measured by an ELISA. E2 occupied 34% of the whole estrogenicity in the raw sewage, while almost 100% in the final effluent. The analyses of the sewage treatment process waters revealed that human estrogens are major causative substances in terms of estrogenic activity in sewage and its treated effluent. Although findings of possible correlation of environmental estrogens with the real impact on human health and the ecosystem are still the focus of scientific debate and investigation, proper management should be established in the sewage treatment process which receives various environmental contaminants.
About Me
Area of expertise:Proteomics for precision medicine
Area of expertise:Proteomics for precision medicine