340 research outputs found

    Anspruch und Wirklichkeit in der universitären Lehrerinnen- und Lehrerbildung am Beispiel des Universitätsstandortes Wien

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    Anspruch und Wirklichkeit in der universitären Lehrerinnen- und Lehrerbildung am Beispiel des Universitätsstandortes Wien. Evaluation der allgemeinen pädagogischen Ausbildung und des Schul-praktikums. Schwerpunkt der Arbeit ist die Evaluation der allgemeinen pädagogischen Ausbildung und des Schulpraktikums im Rahmen des universitären Lehramtsstudiums im Wintersemester 200/01. Mittels Fragebögen wurden rund 40.000 Einzeldaten erhoben, ergänzt durch verbale Stellungnahmen. Das Sample umfasst rund 140 Studierende und ca. 80 BetreuungslehrerInnen aus dem Raum Ostösterreich. Die Ergebnisse dieser Befragung werden mit der Auswertung einer ähnlich konzipierten Studie aus dem Jahr 1991 verglichen. Es zeigt sich, dass durch die Weiterentwicklung und Neuorientierung des pädago-gischen Begleitstudiums wesentliche qualitative Verbesserungen erreicht werden konnten und dass der Stellenwert dieser Bereiche (allgemeine pädagogische Aus-bildung, Schulpraktikum) innerhalb des gesamten Lehramtsstudiums für die Studierenden deutlich gestiegen ist. Gleichzeitig werden konkrete Kritikpunkte und Problemzonen in der prinzipiellen Struktur, in der Durchführung der Lehrver-anstaltungen und im Bereich der Hochschuldidaktik herausgearbeitet. Deutlich wird auf die Notwendigkeit der Ausbildung einer theoriegestützten Refle-xionskompetenz, einer frühzeitigen Praxisbegegnung und einer reflektierten Aus-einandersetzung mit der Schulrealität während des Studiums deutlich. Diese notwendige Qualitätssteigerung kann und soll durch ein konkret formuliertes konsekutives Curriculum, durch die kontinuierliche Einbindung von Praxisphasen, durch begleitende Supervision und durch die Forcierung von Lehrveranstaltungen in seminaristischer Form erreicht werden. Der abschließende Gedanke der Arbeit lautet, dass LehrerInnen-Ausbildung und LehrerInnenbildung im umfassenden Sinne innerhalb des universitären Lehramts-studiums ermöglicht werden müssen. Eine Darstellung der Geschichte der universitären LehrerInnenbildung mit dem Schwerpunkt an der Wiener Universität, die Auseinandersetzung mit dem Begriff bzw. die versuchsweise Klärung des Begriffes Evaluation, die Diskussion des Theorie-Praxis-Verhältnisses und die Darlegung notwendiger Schritte in der universitären LehrerInnenbildung („Zukunftsperspektiven“) ergänzen die Arbeit bzw. runden die Arbeit ab. Die Erhebungsgrundlagen (Fragebögen, Textergänzungen Auswertungen) sind auf einer CD-Rom abgespeichert und der schriftlichen Arbeit beigelegt, um weitere detaillierte Forschungen zu ermöglichen.Demands, Claims and Bottom-Line Reality in University-Level Teacher Education at the University of Vienna Evaluation of general teacher education and practical teacher training The focus of this study is the evaluation of general teacher education as well as practical teacher training within the framework of university-level teacher training courses of study. The study took place in the first semester of the 2000/2001 university year. 40,000 pieces of data were collected by means of a questionnaire, complemented partially by extensive personal interviews and statements made by the participants in verbal form. The sample encompasses approximately 140 students together with about 80 qualified teachers from the eastern part of Austria who serve as supervisors. The results of this survey will be compared to the analysis of a similarly-conceived study which was implemented in 1991. The accompanying study demonstrates that the ongoing development and reorientation of general teacher training courses and practical teacher training have resulted in a significant qualitative improvement. Furthermore, their added value and status within the context of the overall teacher training courses of study leading to a university degree, as perceived by the students themselves, have clearly increased. At the same time, specific weaknesses, criticisms and problem areas have been defined - whether in the approach to teaching training, how courses and seminars are actually conducted or in relation to the field of teaching methodologies. This study points out that it is essential to provide students with practical training at an early stage, to ensure that they confront the day-to-day realities of working in schools throughout their university studies, and that they are given broad-based practical competence supported by theoretical know-how. This necessary boost in quality can be achieved by a variety of instruments: through a clearly-defined, evolving curriculum; the ongoing integration of practical training periods; hands-on supervision by qualified teachers and by encouraging the university to hold courses in the form of seminars. Finally, the study concludes that a complete and comprehensive training and education of teachers must be made possible within the framework of university-level courses of study. The evaluation is complemented by a comprehensive summary of the history of university-level teacher education, particularly at Vienna University, a discussion of the issue of evaluation in general, an analysis of the relationship between theory and practice as well as an attempt to define necessary steps to be taken ("future perspectives"). The fundamental basis for this study – questionnaire, text appendices, and evaluation – has been stored on a CD Rom which accompanies the written version. This is designed to allow for further detailed research to take place

    Evaluation of human first trimester decidual and telomerase-transformed endometrial stromal cells as model systems of in vitro decidualization

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    <p>Abstract</p> <p>Background</p> <p>Decidualization, the differentiation process of maternal uterine stromal cells into secretory decidual cells, is a prerequisite for successful implantation and progression of pregnancy. For in vitro differentiation mostly primary human endometrial stromal cells (HESC) isolated from uterine samples after hysterectomy for benign gynaecological diseases are utilised. However, a continuous supply of endometrial tissue is often lacking. Hence, we analysed whether cultivated human decidual stromal cells (HDSC) prepared from first trimester pregnancy terminations may represent an alternative model system for in vitro decidualization. Moreover, based on the expression of critical marker genes these cells were compared to a previously established endometrial stromal cell line during in vitro differentiation.</p> <p>Methods</p> <p>HDSC isolated from decidual tissue attached to first trimester placentae, and telomerase-transformed human endometrial stromal cells (THESC) were characterised by immunofluorescence and differentiated in vitro using either cyclic adenosine monophosphate (cAMP) and/or estrogen (E2)/progesterone (P4). Proliferation was measured by analyzing cumulative cell numbers. Expression of mRNAs encoding progesterone receptor (PR), prolactin (PRL), insulin-like growth factor binding protein-1 (IGFBP1), and Dickkopf-1 (DKK1) was evaluated using quantitative PCR after 3, 6, 9 and 12 days of in vitro differentiation. PRL and IGFBP-1 protein expression was investigated by enzyme-linked immunosorbent assay (ELISA) and Western blotting, respectively. Furthermore, forkhead box O1A (FOXO1A), a critical transcription factor in decidualization, was analysed by immunofluorescence and Western blotting at two different time points of differentiation.</p> <p>Results</p> <p>Treatment with cAMP provoked morphological changes and growth arrest of THESC and HDSC, the latter showing loss of cells after 6 days of treatment. E2P4 stimulation did neither affect cell morphology nor proliferation of THESC and HDSC. Upon cAMP stimulation PR mRNA was suppressed in HDSC but not in THESC, whereas E2P4 did not alter transcript levels in both cell types. Protein expression of PR-A and PR-B was detectable in HDSC and diminished under cAMP, whereas THESC failed to produce the nuclear receptors. Supplementation of cAMP induced mRNA and protein expression of PRL and IGFBP-1 in both cell types at day 3, 6, 9, and 12 of treatment. In HDSC stimulation with E2P4 increased PRL and IGFBP-1 mRNA and protein production, whereas hormone treatment did not induce the two factors in THESC. E2P4 increased DKK1 mRNA at all time points in HDSC and cAMP provoked induction at day 9 and 12 of differentiation. In contrast, cAMP suppressed DKK1 mRNA in THESC, whereas E2P4 was ineffective. In both cell types combined treatments with cAMP and E2P4 provoked higher expression levels of PRL and IGFBP1 mRNA and protein as compared to cAMP stimulation alone. FOXO1A protein and its nuclear abundance were increased by cAMP in both cell types. However, reduction of its nuclear localisation upon E2P4 treatment could only be observed in HDSC.</p> <p>Conclusion</p> <p>Both HDSC and THESC may represent suitable model systems for cAMP-dependent in vitro decidualization. Since cAMP decreases cell viability of HDSC after 6 days of incubation, this substance should be preferentially used in short-term experiments. Progesterone treatment of THESC might not be applicable since these cells lack progesterone response and PR protein. In contrast, stimulation of PR-expressing HDSC with E2P4 or cAMP/E2P4 may represent an appropriate protocol for human in vitro decidualization inducing and maintaining expression of critical marker genes in a time-dependent manner.</p

    Human trophoblast invasion: new and unexpected routes and functions

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    Stem cells & developmental biolog

    Caffeine Inhibits EGF-Stimulated Trophoblast Cell Motility through the Inhibition of mTORC2 and Akt.

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    Impaired trophoblast invasion is associated with pregnancy disorders such as early pregnancy loss and preeclampsia. There is evidence to suggest that the consumption of caffeine during pregnancy may increase the risk of pregnancy loss; however, little is known about the direct effect of caffeine on normal trophoblast biology. Our objectives were to examine the effect of caffeine on trophoblast migration and motility after stimulation with epidermal growth factor (EGF) and to investigate the intracellular signaling pathways involved in this process. Primary first-trimester extravillous trophoblasts (EVT) and the EVT-derived cell line SGHPL-4 were used to study the effect of caffeine on EGF-stimulated cellular motility using time-lapse microscopy. SGHPL-4 cells were further used to study the effect of caffeine and cAMP on EGF-stimulated invasion of fibrin gels. The influence of caffeine and cAMP on EGF-stimulated intracellular signaling pathways leading to the activation of Akt were investigated by Western blot analysis. Caffeine inhibits both EGF-stimulated primary EVT and SGHPL-4 cell motility. EGF stimulation activates phosphatidylinositol 3-kinase, and Akt and caffeine inhibit this activation. Although cAMP inhibits both motility and invasion, it does not inhibit the activation of Akt, indicating that the effects of caffeine seen in this study are independent of cAMP. Further investigation indicated a role for mammalian target of rapamycin complex 2 (mTORC2) as a target for the inhibitory effect of caffeine. In conclusion, we demonstrate that caffeine inhibits EGF-stimulated trophoblast invasion and motility in vitro and so could adversely influence trophoblast biology in vivo

    Increased angiogenic factor secretion by decidual natural killer cells from pregnancies with high uterine artery resistance alters trophoblast function.

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    STUDY QUESTION Are the concentrations of factors secreted by decidual natural killer (dNK) cells from pregnancies at high risk of poor spiral artery remodelling different to those secreted from pregnancies at low risk? SUMMARY ANSWER Expression levels of PLGF, sIL-2R, endostatin and angiogenin were significantly increased by dNK cells from high-risk pregnancies, and angiogenin and endostatin were found to alter trophoblast function. WHAT IS KNOWN ALREADY During early pregnancy, maternal uterine spiral arteries are remodelled from small diameter, low-flow, high-resistance vessels into larger diameter, higher flow vessels, with low-resistance. This change is essential for the developing fetus to obtain sufficient oxygen and nutrients. dNK cells have been implicated in this process. STUDY DESIGN, SIZE, DURATION dNK cells were isolated from first trimester terminations of pregnancies (obtained with local ethical approval) screened for normal- or high-resistance index, indicative of cases least (21%) likely to have developed pre-eclampsia had the pregnancy not been terminated (n = 18 each group). Secreted factors and the effects of these on the trophoblast cell line, SGHPL-4, were assessed in vitro. PARTICIPANTS/MATERIALS, SETTING, METHODS A multiplex assay was used to assess dNK cell-secreted factors. SGHPL-4 cell functions were assessed using time-lapse microscopy, 3D invasion assays, endothelial-like tube formation ability and western blot analysis. MAIN RESULTS AND THE ROLE OF CHANCE The expression levels of PLGF (P < 0.01), sIL-2R (P < 0.01), endostatin (P < 0.05) and angiogenin (P < 0.05) were significantly increased by dNK cells from high-risk pregnancies. Endostatin significantly decreased SGHPL-4 invasion (P < 0.05), SGHPL-4 tube formation (P < 0.05) and SGHPL-4 Aktser473 phosphorylation (P < 0.05). Angiogenin significantly decreased SGHPL-4 invasion (P < 0.05), but increased SGHPL-4 tube formation (P < 0.01) and decreased SGHPL-4 Aktser473 phosphorylation (P < 0.05). LIMITATIONS, REASONS FOR CAUTION The culture of dNK cells and protein concentrations in vitro may not fully represent the in vivo situation. Although SGHPL-4 cells are extravillous trophoblast derived, further studies would be needed to confirm the roles of angiogenin and endostatin in vivo. WIDER IMPLICATIONS OF THE FINDINGS The altered expression of secreted factors of dNK cells may contribute to pregnancy disorders associated with poor spiral artery remodelling. STUDY FUNDING/COMPETING INTEREST(S) This study was supported by the Wellcome Trust (project reference 091550). R.F. was a recipient of a PhD studentship from the Division of Biomedical Sciences, St. George's, University of London. The authors have no conflict of interests

    Tumour invasiveness, the local and systemic environment and the basis of staging systems in colorectal cancer

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    background: The present study aimed to examine the relationship between tumour invasiveness (T stage), the local and systemic environment and cancer-specific survival (CSS) of patients with primary operable colorectal cancer. methods: The tumour microenvironment was examined using measures of the inflammatory infiltrate (Klintrup-Makinen (KM) grade and Immunoscore), tumour stroma percentage (TSP) and tumour budding. The systemic inflammatory environment was examined using modified Glasgow Prognostic Score (mGPS) and neutrophil:lymphocyte ratio (NLR). A 5-year CSS was examined. results: A total of 331 patients were included. Increasing T stage was associated with colonic primary, N stage, poor differentiation, margin involvement and venous invasion (P&lt;0.05). T stage was significantly associated with KM grade (P=0.001), Immunoscore (P=0.016), TSP (P=0.006), tumour budding (P&lt;0.001), and elevated mGPS and NLR (both P&lt;0.05). In patients with T3 cancer, N stage stratified survival from 88 to 64%, whereas Immunoscore and budding stratified survival from 100 to 70% and from 91 to 56%, respectively. The Glasgow Microenvironment Score, a score based on KM grade and TSP, stratified survival from 93 to 58%. conclusions: Although associated with increasing T stage, local and systemic tumour environment characteristics, and in particular Immunoscore, budding, TSP and mGPS, are stage-independent determinants of survival and may be utilised in the staging of patients with primary operable colorectal cancer

    Regulation of Placental Extravillous Trophoblasts by the Maternal Uterine Environment

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    During placentation invasive extravillous trophoblasts (EVTs) migrate into the maternal uterus and modify its vessels. In particular, remodeling of the spiral arteries by EVTs is critical for adapting blood flow and nutrient transport to the developing fetus. Failures in this process have been noticed in different pregnancy complications such as preeclampsia, intrauterine growth restriction, stillbirth, or recurrent abortion. Upon invasion into the decidua, the endometrium of pregnancy, EVTs encounter different maternal cell types such as decidual macrophages, uterine NK (uNK) cells and stromal cells expressing a plethora of growth factors and cytokines. Here, we will summarize development of the EVT lineage, a process occurring independently of the uterine environment, and formation of its different subtypes. Further, we will discuss interactions of EVTs with arteries, veins and lymphatics and illustrate how the decidua and its different immune cells regulate EVT differentiation, invasion and survival. The present literature suggests that the decidual environment and its soluble factors critically modulate EVT function and reproductive success

    Automatic evaluation of tumor budding in immunohistochemically stained colorectal carcinomas and correlation to clinical outcome

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    Background: Tumor budding, meaning a detachment of tumor cells at the invasion front of colorectal carcinoma (CRC) into single cells or clusters (&lt;=5 tumor cells), has been shown to correlate to an inferior clinical outcome by several independent studies. Therefore, it has been discussed as a complementary prognostic factor to the TNM staging system, and it is already included in national guidelines as an additional prognostic parameter. However, its application by manual evaluation in routine pathology is hampered due to the use of several slightly different assessment systems, a time-consuming manual counting process and a high inter-observer variability. Hence, we established and validated an automatic image processing approach to reliably quantify tumor budding in immunohistochemically (IHC) stained sections of CRC samples. Methods: This approach combines classical segmentation methods (like morphological operations) and machine learning techniques (k-means and hierarchical clustering, convolutional neural networks) to reliably detect tumor buds in colorectal carcinoma samples immunohistochemically stained for pan-cytokeratin. As a possible application, we tested it on whole-slide images as well as on tissue microarrays (TMA) from a clinically well-annotated CRC cohort. Results: Our automatic tumor budding evaluation tool detected the absolute number of tumor buds per image with a very good correlation to the manually segmented ground truth (R2 value of 0.86). Furthermore the automatic evaluation of whole-slide images from 20 CRC-patients, we found that neither the detected number of tumor buds at the invasion front nor the number in hotspots was associated with the nodal status. However, the number of spatial clusters of tumor buds (budding hotspots) significantly correlated to the nodal status (p-value = 0.003 for N0 vs. N1/N2). TMAs were not feasible for tumor budding evaluation, as the spatial relationship of tumor buds (especially hotspots) was not preserved. Conclusions: Automatic image processing is a feasible and valid assessment tool for tumor budding in CRC on whole-slide images. Interestingly, only the spatial clustering of the tumor buds in hotspots (and especially the number of hotspots) and not the absolute number of tumor buds showed a clinically relevant correlation with patient outcome in our data

    Host and microbiome features of secondary infections in lethal covid-19

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    Secondary infections contribute significantly to covid-19 mortality but driving factors remain poorly understood. Autopsies of 20 covid-19 cases and 14 controls from the first pandemic wave complemented with microbial cultivation and RNA-seq from lung tissues enabled description of major organ pathologies and specification of secondary infections. Lethal covid-19 segregated into two main death causes with either dominant diffuse alveolar damage (DAD) or secondary pneumonias. The lung microbiome in covid-19 showed a reduced biodiversity and increased prototypical bacterial and fungal pathogens in cases of secondary pneumonias. RNA-seq distinctly mirrored death causes and stratified DAD cases into subgroups with differing cellular compositions identifying myeloid cells, macrophages and complement C1q as strong separating factors suggesting a pathophysiological link. Together with a prominent induction of inhibitory immune-checkpoints our study highlights profound alterations of the lung immunity in covid-19 wherein a reduced antimicrobial defense likely drives development of secondary infections on top of SARS-CoV-2 infection
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