393 research outputs found

    A polymer analogous reaction for the formation of imidazolium and NHC based porous polymer networks

    Get PDF
    Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.A polymer analogous reaction was carried out to generate a porous polymeric network with N-heterocyclic carbenes (NHC) in the polymer backbone. Using a stepwise approach, first a polyimine network is formed by polymerization of the tetrafunctional amine tetrakis(4-aminophenyl)methane. This polyimine network is converted in the second step into polyimidazolium chloride and finally to a polyNHC network. Furthermore a porous Cu(II)-coordinated polyNHC network can be generated. Supercritical drying generates polymer networks with high permanent surface areas and porosities which can be applied for different catalytic reactions. The catalytic properties were demonstrated for example in the activation of CO2 or in the deoxygenation of sulfoxides to the corresponding sulfides.BMBF, 01RC0901F, Dream Reactions - Stoffliche CO2-VerwertungDFG, EXC 314, Unifying Concepts in Catalysi

    Rare human papillomavirus 16 E6 variants reveal significant oncogenic potential

    Get PDF
    The aim of this study was to determine whether low prevalence human papillomavirus (HPV) 16 E6 variants differ from high prevalence types in their functional abilities. We evaluated functions relevant to carcinogenesis for the rarely-detected European variants R8Q, R10G and R48W as compared to the commonly detected L83V. Human immortalized keratinocytes (NIKS) stably transduced with the E6 variants were used in most functional assays. Low and high prevalence E6 variants displayed similar abilities in abrogation of growth arrest and inhibition of p53 elevation induced by actinomycin D. Differences were detected in the abilities to dysregulate stratification and differentiation of NIKS in organotypic raft cultures, modulate detachment induced apoptosis (anoikis) and hyperactivate Wnt signaling. No distinctive phenotype could be assigned to include all rare variants. Like L83V, raft cultures derived from variants R10G and R48W similarly induced hyperplasia and aberrantly expressed keratin 5 in the suprabasal compartment with significantly lower expression of keratin 10. Unlike L83V, both variants, and particularly R48W, induced increased levels of anoikis upon suspension in semisolid medium. R8Q induced a unique phenotype characterized by thin organotypic raft cultures, low expression of keratin 10, and high expression of keratins 5 and 14 throughout all raft layers. Interestingly, in a reporter based assay R8Q exhibited a higher ability to augment TCF/β-catenin transcription. The data suggests that differences in E6 variant prevalence in cervical carcinoma may not be related to the carcinogenic potential of the E6 protein

    Toll-Like Receptor Transcriptome in the HPV-Positive Cervical Cancer Microenvironment

    Get PDF
    The human papillomavirus (HPV) directly infects cervical keratinocytes and interferes with TLR signalling. To shed light on the effect of HPV on upstream receptors, we evaluated TLRs 1–9 gene expression in HPV-negative normal and HPV-positive pre-malignant and malignant ex vivo cervical tissue. Quantitative real-time polymerase chain reaction was performed separately for epithelial and stromal tissue compartments. Differences in gene expression were analyzed by the Jonckheere-Terpstra trend test or the Student's t-test for pairwise comparison. Laser capture microdissection revealed an increase in TLR3 and a decrease in TLR1 mRNA levels in dysplastic and carcinoma epithelium, respectively. In the stroma, a trend of increasing TLR 1, 2, 5, 6, and 9 mRNA levels with disease severity was found. These findings implicate the involvement of TLR3 and TLR1 in early and late cervical carcinogenesis, respectively, suggesting that stromal upregulation of TLRs may play a role in cervical disease progression

    Polyvalenz und Vulneranz. Empirische Perspektiven auf inklusionsorientierte Übergangsgestaltung in Elterngesprächen

    Get PDF
    Der Band präsentiert Ergebnisse einer qualitativ-rekonstruktiven Studie zu Elterngesprächen in integrativen Kindertageseinrichtungen. In Anlehnung an ein praxeologisches Übergangs- und Inklusionsverständnis wird eine Typologie dieser Gespräche vorgelegt. Als wesentliches Ergebnis der Studie lassen sich eine erhöhte Polyvalenz (Vieldeutigkeit) und Vulneranz, die sich aus der Verletzlichkeit der Eltern speist, ausmachen sowie als zentrale Herausforderung einer inklusiven (Früh-)Pädagogik ausweisen. Zudem werden Formen einer inklusionsorientierten Übergangsgestaltung herausgearbeitet. (DIPF/Orig.

    Hochbegabung und soziale Ungleichheit in der frühen Kindheit

    Get PDF
    Gegenstand der Publikation ist das Verhältnis von Hochbegabung und sozialer Ungleichheit in der frühen Kindheit. Dabei wird der Fokus auf die pädagogische Arbeit in Kindertageseinrichtungen gelegt. Zunächst wird der Begriff der Hochbegabung als hohe intellektuelle Begabung erschlossen, anschließend im Kontext von Inklusion die Bedeutung der Kindertageseinrichtungen für die Entwicklung hoher kognitiver Begabungen herausgestellt und schließlich mehrdimensional das Verhältnis von Hochbegabung und sozialer Ungleichheit betrachtet. Aus den Erkenntnissen werden Handlungsempfehlungen abgeleitet. (DIPF/Orig.

    Functional variants of human papillomavirus type 16 demonstrate host genome integration and transcriptional alterations corresponding to their unique cancer epidemiology

    Get PDF
    BACKGROUND: Human papillomaviruses (HPVs) are a worldwide burden as they are a widespread group of tumour viruses in humans. Having a tropism for mucosal tissues, high-risk HPVs are detected in nearly all cervical cancers. HPV16 is the most common high-risk type but not all women infected with high-risk HPV develop a malignant tumour. Likely relevant, HPV genomes are polymorphic and some HPV16 single nucleotide polymorphisms (SNPs) are under evolutionary constraint instigating variable oncogenicity and immunogenicity in the infected host. RESULTS: To investigate the tumourigenicity of two common HPV16 variants, we used our recently developed, three-dimensional organotypic model reminiscent of the natural HPV infectious cycle and conducted various “omics” and bioinformatics approaches. Based on epidemiological studies we chose to examine the HPV16 Asian-American (AA) and HPV16 European Prototype (EP) variants. They differ by three non-synonymous SNPs in the transforming and virus-encoded E6 oncogene where AAE6 is classified as a high- and EPE6 as a low-risk variant. Remarkably, the high-risk AAE6 variant genome integrated into the host DNA, while the low-risk EPE6 variant genome remained episomal as evidenced by highly sensitive Capt-HPV sequencing. RNA-seq experiments showed that the truncated form of AAE6, integrated in chromosome 5q32, produced a local gene over-expression and a large variety of viral-human fusion transcripts, including long distance spliced transcripts. In addition, differential enrichment of host cell pathways was observed between both HPV16 E6 variant-containing epithelia. Finally, in the high-risk variant, we detected a molecular signature of host chromosomal instability, a common property of cancer cells. CONCLUSIONS: We show how naturally occurring SNPs in the HPV16 E6 oncogene cause significant changes in the outcome of HPV infections and subsequent viral and host transcriptome alterations prone to drive carcinogenesis. Host genome instability is closely linked to viral integration into the host genome of HPV-infected cells, which is a key phenomenon for malignant cellular transformation and the reason for uncontrolled E6 oncogene expression. In particular, the finding of variant-specific integration potential represents a new paradigm in HPV variant biology. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12864-016-3203-3) contains supplementary material, which is available to authorized users

    Colonial legacy and the experience of First Nations women in cervical cancer screening: a Canadian multi-community study

    Get PDF
    This is an Accepted Manuscript of an article published by Taylor & Francis in Critical Public health on July 22, 2015, available online: http://dx.doi.org/10.1080/09581596.2015.1067671Regular Papanicolaou (Pap) screening has dramatically reduced cervical cancer incidence in Canada since the 1950s. However, Indigenous women’s rates of cervical cancer remain disproportionately high, a factor which is not acknowledged in national media or in educational materials reporting Canada’s new cervical cancer screening guidelines. Here, we present findings from a cervical cancer screening initiative in Northwestern Ontario. Based on participatory action research, we worked with 10 First Nations communities in the Robinson Superior Treaty area to increase awareness of cervical cancer risk, develop culturally sensitive tools for screening and education and test the efficacy of human papillomavirus (HPV) self-sampling as an alternative to Pap cytology. We conducted 16 interviews with health care professionals and 9 focus groups with 69 women from the communities. A central theme for both health care providers (HCPs) and community members was the colonial legacy and its influence on women’s experiences of cervical cancer screening. This was evidenced by a strong sense of body shyness, including shame related to sexuality and sexually transmitted infections, concerns about confidentiality in clinical encounters and distrust or caution around HCPs. Reaffirming women’s traditional caregiving and educational roles, enhancing mother and daughter communication, improving cultural sensitivity in health care and education and adoption of HPV self-sampling to increase women’s privacy and control of the cervical cancer screening experience were endorsed. We argue that education and screening initiatives must reflect the cultural preferences of Indigenous women, empowering them to take control of their experiences of health and body in cervical cancer screening
    corecore