Possible role of the phagocytic proteinases, cathepsin B and elastas, in orthotopic liver transplantation

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Possible role of extracellularly released phagocytic proteinases in the coagulation disorder during liver transplantation

Orthotopic liver transplantation is frequently associated with a complex coagulation disorder, influencing the outcome of the procedure. In this respect, disseminated intravascular coagulation (DIC) had been suggested to be of causative importance for bleeding complications after reperfusion of the liver graft. In 10 consecutive patients undergoing orthotopic liver transplantations, we studied the occurrence of two phagocyte proteinases of different origin in the graft liver perfus-ate and in systemic blood during the operation, as well as their effects on hemostasis. As compared with plasma samples taken at the end of the anhepatic phase, highly significant increases of cathepsin B and thrombin-anti-thrombin III complexes (TAT), as well as highly significant decreases in antithrombin III, protein C, and C1-inhibitor were observed in graft liver perfusate. Von Willebrand factor and fibrinogen were slightly decreased, whereas the elastase-alpha1 proteinase inhibitor complexes (EPI) were elevated. In plasma the activity of cathepsin B remained unchanged during the prereperfusion phases, but immediately after revascularization of the graft this cysteine proteinase increased. The EPI showed a gradual increase in plasma during the preanhepatic and anhepatic phases but a more pronounced increase in the reperfusion phase. In parallel with the rise in these two proteinases TAT increased and the activities of antithrombin III and C1-inhibitor in plasma decreased after reperfusion. At 12 hr after revascularization plasma levels of TAT, antithrombin III, and C1-inhibitor had returned to the prereperfusion ranges, whereas cathepsin B and EPI were significantly above the baseline levels. These observations are consistent with the hypothesis that extracellularly released lysosomal proteinases may play a role in the development of a DIC-like constellation, including thrombin formation after revascularization of the liver graft. For the first time we could prove the occurrence of phagocyte proteinases in graft liver perfusate and evaluate the importance of these proteinases for the understanding of the pathophysiology leading to bleeding complications in patients undergoing orthotopic liver transplantation

Intracellular Nanoparticle Coating Stability Determines Nanoparticle Diagnostics Efficacy and Cell Functionality

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“Conline” Teaching: Creative pedagogy as a conduit to EAP practitioners’ agency

Whilst an important 21st century graduate attribute, creativity is difficult to define because of its multi-dimensional nature and variety of epistemological perspectives adopted in scholarly discussions. Some have focused on the subjectivity behind the output as demonstrated in expressivist writing pedagogies (Elbow, 1991), while others have explored collaborative knowledge production and its social context (Montuori, 2006; Goldsmith, 2011; Hafner, 2015). When it comes to EAP, scholarship on how creativity is understood and deployed is fragmented, with studies exploring the use of specific techniques such as gaming, creative arts or object handling for the development of individual competencies (e.g., Saliés, 2002; Carson&Murphy, 2012; Bond, 2018; Richards&Pilcher, 2020), the focus largely remaining text-oriented (Hyland, 2018) and delimited by the “pragmatic” nature of EAP. In this presentation, we will provide an overview of an ongoing multi-methods arts-informed inquiry into EAP practitioners’ creative voices through a snapshot analysis of the findings from one pilot dataset. We will focus on the prominence of the theme of collaboration and co-construction as fundamental to creative practices in EAP, but also consider the extent to which creative pedagogy as a paradigm opens up a fuzzy yet enabling “third space” (Bhabha, 1994) for the enactment of EAP practitioners’ agency. References: Bhabha, H. 1994. The Location of Culture. London and New York: Routledge. Bond, M. 2018. Teaching referencing and plagiarism awareness Using LEGO® SERIOUS PLAY®. International Journal of Management and Applied Research. 5 (4), pp. 232–37. Carson, L. and Murphy, D. 2012. Design and implementation of dramatic tasks in an English for Academic Purposes programme. Language Learning in Higher Education. 1 (1), pp.127–42. Elbow, P. 1991. Some thoughts on “expressive discourse”: A review essay. Journal of Advanced Composition. 11 (1), pp.83–93. Goldsmith, K. 2011. Uncreative Writing. New York: Columbia University Press. Hafner, C. A. 2015. Remix Culture and English Language Teaching: The Expression of Learner Voice in Digital Multimodal Compositions. TESOL Quarterly. 49 (3), pp.486–509. Montuori, A. 2006. The quest for a new education: From oppositional identities to creative inquiry. ReVision. 28(3), pp.4–20. Richards, K. and Pilcher, N. 2020. Using physical objects as a portal to reveal academic subject identity and thought. The Qualitative Report. 25(1), pp.127–44. Saliés, T. G. 2002. Simulation/Gaming in the EAP Writing Class: Benefits and Drawbacks. Simulation & Gaming. 33(3), pp.316–29

Rapid Etiological Classification of Meningitis by NMR Spectroscopy Based on Metabolite Profiles and Host Response

Bacterial meningitis is an acute disease with high mortality that is reduced by early treatment. Identification of the causative microorganism by culture is sensitive but slow. Large volumes of cerebrospinal fluid (CSF) are required to maximise sensitivity and establish a provisional diagnosis. We have utilised nuclear magnetic resonance (NMR) spectroscopy to rapidly characterise the biochemical profile of CSF from normal rats and animals with pneumococcal or cryptococcal meningitis. Use of a miniaturised capillary NMR system overcame limitations caused by small CSF volumes and low metabolite concentrations. The analysis of the complex NMR spectroscopic data by a supervised statistical classification strategy included major, minor and unidentified metabolites. Reproducible spectral profiles were generated within less than three minutes, and revealed differences in the relative amounts of glucose, lactate, citrate, amino acid residues, acetate and polyols in the three groups. Contributions from microbial metabolism and inflammatory cells were evident. The computerised statistical classification strategy is based on both major metabolites and minor, partially unidentified metabolites. This data analysis proved highly specific for diagnosis (100% specificity in the final validation set), provided those with visible blood contamination were excluded from analysis; 6-8% of samples were classified as indeterminate. This proof of principle study suggests that a rapid etiologic diagnosis of meningitis is possible without prior culture. The method can be fully automated and avoids delays due to processing and selective identification of specific pathogens that are inherent in DNA-based techniques

The human somatostatin receptor type 2 as an imaging and suicide reporter gene for pluripotent stem cell-derived therapy of myocardial infarction

Rationale: Pluripotent stem cells (PSCs) are being investigated as a cell source for regenerative medicine since they provide an infinitive pool of cells that are able to differentiate towards every cell type of the body. One possible therapeutic application involves the use of these cells to treat myocardial infarction (MI), a condition where billions of cardiomyocytes (CMs) are lost. Although several protocols have been developed to differentiate PSCs towards CMs, none of these provide a completely pure population, thereby still posing a risk for neoplastic teratoma formation. Therefore, we developed a strategy to (i) monitor cell behavior noninvasively via site-specific integration of firefly luciferase (Fluc) and the human positron emission tomography (PET) imaging reporter genes, sodium iodide symporter (hNIS) and somatostatin receptor type 2 (hSSTr2), and (ii) perform hSSTr2-mediated suicide gene therapy via the clinically used radiopharmacon 177Lu-DOTATATE. Methods: Human embryonic stem cells (ESCs) were gene-edited via zinc finger nucleases to express Fluc and either hNIS or hSSTr2 in the safe harbor locus, adeno-associated virus integration site 1. Firstly, these cells were exposed to 4.8 MBq 177Lu-DOTATATE in vitro and cell survival was monitored via bioluminescence imaging (BLI). Afterwards, hNIS+ and hSSTr2+ ESCs were transplanted subcutaneously and teratomas were allowed to form. At day 59, baseline 124I and 68Ga-DOTATATE PET and BLI scans were performed. The day after, animals received either saline or 55 MBq 177Lu-DOTATATE. Weekly BLI scans were performed, accompanied by 124I and 68Ga-DOTATATE PET scans at days 87 and 88, respectively. Finally, hSSTr2+ ESCs were differentiated towards CMs and transplanted intramyocardially in the border zone of an infarct that was induced by left anterior descending coronary artery ligation. After transplantation, the animals were monitored via BLI and PET, while global cardiac function was evaluated using cardiac magnetic resonance imaging. Results: Teratoma growth of both hNIS+ and hSSTr2+ ESCs could be followed noninvasively over time by both PET and BLI. After 177Lu-DOTATATE administration, successful cell killing of the hSSTr2+ ESCs was achieved both in vitro and in vivo, indicated by reductions in total tracer lesion uptake, BLI signal and teratoma volume. As undifferentiated hSSTr2+ ESCs are not therapeutically relevant, they were differentiated towards CMs and injected in immune-deficient mice with a MI. Long-term cell survival could be monitored without uncontrolled cell proliferation. However, no improvement in the left ventricular ejection fraction was observed.Conclusion: We developed isogenic hSSTr2-expressing ESCs that allow noninvasive cell monitoring in the context of PSC-derived regenerative therapy. Furthermore, we are the first to use the hSSTr2 not only as an imaging reporter gene, but also as a suicide mechanism for radionuclide therapy in the setting of PSC-derived cell treatment