37 research outputs found
Polyglycerol coated polypropylene surfaces for protein and bacteria resistance
Polyglycerol (PG) coated polypropylene (PP) films were synthesized in a two-
step approach that involved plasma bromination and subsequently grafting
hyperbranched polyglycerols with very few amino functionalities. The influence
of different molecular weights and density of reactive linkers were
investigated for the grafted PGs. Longer bromination times and higher amounts
of linkers on the surface afforded long-term stability. The protein adsorption
and bacteria attachment of the PP-PG films were studied. Their extremely low
amine content proved to be beneficial for preventing bacteria attachment
Aspekte der Testgüte bei der Erfassung schulischer Kompetenzen von Schülerinnen und Schülern mit sonderpädagogischem Förderbedarf
Im Beitrag wurde geprüft, inwieweit die im IQB-Ländervergleich 2011 in der Primarstufe eingesetzten Kompetenztests in Deutsch und Mathematik dazu geeignet sind, auch die Kompetenzen von Schülerinnen und Schülern mit sonderpädagogischem Förderbedarf (SPF) adäquat zu erfassen. Dazu wurden der Anteil fehlender Werte, die Passung des Raschmodells, differenzielle ltemfunktionalität und Korrelationen der Testwerte zwischen den Schülergruppen mit SPF in Förder- und Grundschulen und Kindern ohne SPF analysiert. Die eingesetzten Tests scheinen die schulischen Kompetenzen von Kindern mit SPF reliabel und valide zu erfassen. Allerdings zeigten sich Einschränkungen hinsichtlich der Vergleichbarkeit der Messungen für Kinder in Förderschulen in Mathematik. (DIPF/Orig.)In 2011, students with special educational needs (SEN) were part of the sample of the National Assessment Study (IQB-Ländervergleich 2011) in primary schools. The study examines if the achievement tests in German and Mathematics are also suited to assess SEN students\u27 proficiencies. To evaluate the structural validity of the achievement tests for SEN students in special education and regular schools, missing patterns, the fit of the Rasch model, differential item functioning, and correlations of the test scores were analyzed. Results show that the achievement tests captured the same proficiencies in similar ways for SEN students compared to students without SEN. However, comparability of the achievement tests in Mathematics was reduced for students in special education schools. (DIPF/Orig.
Nos2 Inactivation Promotes the Development of Medulloblastoma in Ptch1+/− Mice by Deregulation of Gap43–Dependent Granule Cell Precursor Migration
Medulloblastoma is the most common malignant brain tumor in children. A subset of medulloblastoma originates from granule cell precursors (GCPs) of the developing cerebellum and demonstrates aberrant hedgehog signaling, typically due to inactivating mutations in the receptor PTCH1, a pathomechanism recapitulated in Ptch1+/− mice. As nitric oxide may regulate GCP proliferation and differentiation, we crossed Ptch1+/− mice with mice lacking inducible nitric oxide synthase (Nos2) to investigate a possible influence on tumorigenesis. We observed a two-fold higher medulloblastoma rate in Ptch1+/− Nos2−/− mice compared to Ptch1+/− Nos2+/+ mice. To identify the molecular mechanisms underlying this finding, we performed gene expression profiling of medulloblastomas from both genotypes, as well as normal cerebellar tissue samples of different developmental stages and genotypes. Downregulation of hedgehog target genes was observed in postnatal cerebellum from Ptch1+/+ Nos2−/− mice but not from Ptch1+/− Nos2−/− mice. The most consistent effect of Nos2 deficiency was downregulation of growth-associated protein 43 (Gap43). Functional studies in neuronal progenitor cells demonstrated nitric oxide dependence of Gap43 expression and impaired migration upon Gap43 knock-down. Both effects were confirmed in situ by immunofluorescence analyses on tissue sections of the developing cerebellum. Finally, the number of proliferating GCPs at the cerebellar periphery was decreased in Ptch1+/+ Nos2−/− mice but increased in Ptch1+/− Nos2−/− mice relative to Ptch1+/− Nos2+/+ mice. Taken together, these results indicate that Nos2 deficiency promotes medulloblastoma development in Ptch1+/− mice through retention of proliferating GCPs in the external granular layer due to reduced Gap43 expression. This study illustrates a new role of nitric oxide signaling in cerebellar development and demonstrates that the localization of pre-neoplastic cells during morphogenesis is crucial for their malignant progression
How Much Information Does a Human Translator Add to the Original?
We ask how much information a human translator adds to an original text, and we provide a bound. We address this ques-tion in the context of bilingual text com-pression: given a source text, how many bits of additional information are required to specify the target text produced by a hu-man translator? We develop new compres-sion algorithms and establish a benchmark task.
Regulation of genes involved in cell cylce regulation in androgen-sensitive and androgen-independent LNCaP prostate cancer cells subjected to androgen receptor protein down regulation
Analyses of single extracellular vesicles from non-small lung cancer cells to reveal effects of epidermal growth factor receptor inhibitor treatments
Precision cancer medicine has changed the treatment landscape of non-small cell lung cancer (NSCLC) as illustrated by the introduction of tyrosine kinase inhibitors (TKIs) towards mutated epidermal growth factor receptor (EGFR). However, as responses to EGFR-TKIs are heterogenous among NSCLC patients, there is a need for ways to early monitor changes in treatment response in a non-invasive way e.g., in patient's blood samples. Recently, extracellular vesicles (EVs) have been identified as a source of tumor biomarkers which could improve on non-invasive liquid biopsy-based diagnosis of cancer. However, the heterogeneity in EVs is high. Putative biomarker candidates may be hidden in the differential expression of membrane proteins in a subset of EVs hard to identify using bulk techniques. Using a fluorescence-based approach, we demonstrate that a single-EV tech-nique can detect alterations in EV surface protein profiles. We analyzed EVs isolated from an EGFR-mutant NSCLC cell line, which is refractory to EGFR-TKIs erlotinib and responsive to osimertinib, before and after treatment with these drugs and after cisplatin chemotherapy. We studied expression level of five proteins; two tetraspanins (CD9, CD81), and three markers of interest in lung cancer (EGFR, programmed death-ligand 1 (PD-L1), human epidermal growth factor receptor 2 (HER2)). The data reveal alterations induced by the osimertinib treatment compared to the other two treatments. These include the growth of the PD-L1/HER2-positive EV population, with the largest increase in vesicles exclusively expressing one of the two proteins. The expression level per EV decreased for these markers. On the other hand, both the TKIs had a similar effect on the EGFR-positive EV population
Digital teaching as an instrument for cross-location teaching networks in medical informatics: opportunities and challenges - Digitale Lehre als Instrument für standortübergreifende Lehrverbünde in Medizinischer Informatik: Chancen und Herausforderungen
Benning N-H, Haag M, Knaup P, et al. Digital teaching as an instrument for cross-location teaching networks in medical informatics: opportunities and challenges - Digitale Lehre als Instrument für standortübergreifende Lehrverbünde in Medizinischer Informatik: Chancen und Herausforderungen. GMS Journal for Medical Education. 2020;37(6).The increasingly digitized healthcare system requires new skills from all those involved. In order to impart these competencies, appropriate courses must be developed at educational institutions. In view of the rapid development of new aspects of digitization, this presents a challenge; suitable teaching formats must be developed successively. The establishment of cross-location teaching networks is one way to better meet training needs and to make the necessary spectrum of educational content available. As part of the Medical Informatics Initiative, the HiGHmed consortium is establishing such a teaching network, in the field of medical informatics, which covers many topics related to the digitization of the health care system. Various problem areas in the German education system were identified that hinder the development of the teaching network. These problem areas were prioritized firstly according to the urgency of the solution from the point of view of the HiGHmed consortium and secondly according to existing competencies in the participating societies. A workshop on the four most relevant topics was organized with experts from the German Society for Medical Informatics, Biometry and Epidemiology (GMDS), the Society for Medical Education (GMA) and the HiGHmed consortium. These are: recognition of exam results from teaching modules that are offered digitally and across locations, and their integration into existing curricula; recognition of digital, cross-location teaching in the teachers' teaching load; nationwide uniform competencies for teachers, in order to be able to conduct digital teaching effectively and with comparable quality; technical infrastructure to efficiently and securely communicate and manage the recognition of exam results between educational institutions. For all subject areas, existing preliminary work was identified on the basis of working questions, and short- and long-term needs for action were formulated. Finally, a need for the redesign of a technologically supported syntactic and semantic interoperability of learning performance recording was identified.Das zunehmend digitalisierte Gesundheitswesen erfordert neue Kompetenzen von allen Beteiligten. Um diese Kompetenzen vermitteln zu können, müssen an den Bildungsinstitutionen entsprechende Lehrveranstaltungen entwickelt werden. Dies ist angesichts der rasanten Entwicklung neuer Digitalisierungsaspekte eine Herausforderung; passende Lehrformate müssen sukzessive aufgebaut werden. Die Etablierung standortübergreifender Lehrverbünde ist eine Möglichkeit, den Ausbildungsbedarf besser zu decken und die notwendige Bandbreite an Bildungsinhalten verfügbar zu machen. Im Rahmen der Medizininformatik-Initiative wird im HiGHmed-Konsortium ein solcher Lehrverbund im Fachgebiet der Medizinischen Informatik aufgebaut, in welches viele Themen der Digitalisierung des Gesundheitswesens fallen. Dabei wurden verschiedene Problemfelder im deutschen Bildungswesen identifiziert, welche den Aufbau des Lehrverbundes hemmen. Diese Problemfelder wurden unter Beachtung der Dringlichkeit der Lösung aus Sicht des HiGHmeducation Konsortiums und andererseits nach vorhandenen Kompetenzen in den teilnehmenden Fachgesellschaften priorisiert. Zu den vier relevantesten Themen wurde ein Workshop mit Fachleuten der deutschen Gesellschaft für Medizinische Informatik, Biometrie und Epidemiologie (GMDS), der Gesellschaft für Medizinische Ausbildung (GMA) und des HiGHmed Konsortiums ausgerichtet. Diese sind: Anerkennung von Prüfungsleistungen aus Lehrmodulen, welche digital und standortübergreifend angeboten werden, und Integration in bestehende Curricula; Anerkennung digitaler, standortübergreifender Lehre im Deputat der Lehrenden; bundesweit einheitliche Kompetenzen für Lehrende, um digitale Lehre effektiv und mit vergleichbarer Qualität betreiben zu können; technische Infrastrukturen, um die Anerkennung zwischen Bildungseinrichtungen effizient und sicher kommunizieren und verwalten zu können. Für alle Themengebiete wurden anhand von Arbeitsfragen existierende Vorarbeiten identifiziert sowie kurz- und langfristige Handlungsbedarfe formuliert. Abschließend wurde themenübergreifend ein Bedarf für die Neugestaltung einer technologisch unterstützten syntaktischen und semantischen Interoperabilität der Erfassung von Lernleistungen festgestellt
miRNA-expression in tonsillar squamous cell carcinomas in relation to HPV infection and expression of the antileukoproteinase SLPI
The aim of this study was to determine if micro-(mi-)RNAs are involved in the previously reported inverse correlation between the antileukoproteinase SLPI, HPV, and smoking habit of head and neck squamous cells carcinoma (HNSCC) patients.HPV-status and SLPI-protein expression were determined in tonsillar SCC (TSCC; n=126). Differentially expressed miRNAs dependent on HPV-status and SLPI-expression were detected by microarray; possible binding-sites in SLPI- and HPVE6-mRNAs were determined in silico. Survival rates were estimated testing prognostic values of HPV-status, SLPI- and miRNA-expression.miRNA-array identified 24 up-regulated and 10 down-regulated miRNAs in HPV-positive versus HPV-negative TSCC (p<0.01; HPV-positivity: 42.1%). HPV-positivity resulted in two up-regulated miRNAs in SLPI-positive TSCC. Of 16 further miRNAs, eight miRNAs were up- and eight were down-regulated in SLPI-negative TSCC. RT-q-PCR-validation of the four most differentially expressed miRNAs showed that miR-363 is expressed strongest in SLPI-negative/HPV-positive TSSC. In silico-analysis of all differentially expressed miRNAs identified miR-363, miR-210, miR-130a, and miR-181a with possible binding sites in the HPV16-E6-mRNA, but none were predicted in the SLPI-mRNA. HPV-positivity, low SLPI-levels and high miR-363-levels are significantly associated with better survival rates.The data presented here show that miR-363 is associated with HPV-positive/SPLI-negative TSCC. The prognostic value of miR-363 suggests a role in the assumed inverse correlation of smoking and SPLI-expression in the mode of HPV-infections in tonsillar but possibly also other HNSCC. Keywords: SLPI, HNSCC, Tonsils, Survival, HPV, miRN