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41.
Jonas Feldheim Almuth F. Kessler Julia J. Feldheim Ellina Schulz David Wend Lazaros Lazaridis Christoph Kleinschnitz Martin Glas Ralf-Ingo Ernestus Sebastian Brandner Camelia M. Monoranu Mario Lhr Carsten Hagemann 《International journal of molecular sciences》2022,23(9)
Glioblastoma leads to a fatal course within two years in more than two thirds of patients. An essential cornerstone of therapy is chemotherapy with temozolomide (TMZ). The effect of TMZ is counteracted by the cellular repair enzyme O6-methylguanine-DNA methyltransferase (MGMT). The MGMT promoter methylation, the main regulator of MGMT expression, can change from primary tumor to recurrence, and TMZ may play a significant role in this process. To identify the potential mechanisms involved, three primary stem-like cell lines (one astrocytoma with the mutation of the isocitrate dehydrogenase (IDH), CNS WHO grade 4 (HGA)), and two glioblastoma (IDH-wildtype, CNS WHO grade 4) were treated with TMZ. The MGMT promoter methylation, migration, proliferation, and TMZ-response of the tumor cells were examined at different time points. The strong effects of TMZ treatment on the MGMT methylated cells were observed. Furthermore, TMZ led to a loss of the MGMT promoter hypermethylation and induced migratory rather than proliferative behavior. Cells with the unmethylated MGMT promoter showed more aggressive behavior after treatment, while HGA cells reacted heterogenously. Our study provides further evidence to consider the potential adverse effects of TMZ chemotherapy and a rationale for investigating potential relationships between TMZ treatment and change in the MGMT promoter methylation during relapse. 相似文献
42.
Julia Peck 《History of Photography》2013,37(3):214-233
This paper re-investigates notions of performed Aboriginality in relation to photographs made at Lake Tyers Mission Station, Victoria, Australia, and argues that Nicholas Caire's photographs reveal complex Aboriginal subjectivities. The photographs, made originally in 1886 and distributed to tourists, were later reproduced and circulated in book format in 1897. The first presentation of the photographs, whilst focusing on historical Aboriginality, contains traces of cross-cultural hybridity. However, the later presentation of the work reinforces historical and traditional material culture over cross-cultural dialogue. This paper argues that the desire to find historical notions of Aboriginality on mission stations in Victoria was not just due to the establishment of hierarchical racial theories in the latter part of the nineteenth century (generating the idea that Aborigines could not change and adapt to notions of ‘civilisation’) and doubts about the success of mission stations, but also because there was an interest in Aborigines who had experienced little assimilation from more remote parts of the continent of Australia. This curiosity in pre-contact Aboriginality fuelled tourism in Victoria to accessible mission stations such as Lake Tyers. 相似文献
43.
Julia Peck 《Photographies》2016,9(1):71-89
Jane Bennett’s thesis in Vibrant Matter argues that we need to find ways to acknowledge and engage with the agency of all factors that create ecologies and environments, including non-human actants. This essay argues that Richard Misrach and Kate Orff’s project Petrochemical America signals some important strategies that are useful for developing visual political ecologies and understanding non-human actants, including the non-living. Although some of the images are typical scenes of environmental devastation, human and social links are made to foster the understanding that we are looking at an image of ecology rather than nature ravaged. In addition to the titles of images, captions and overall contextualization of the project, Kate Orff’s team SCAPE produce a series of diagrams called Throughlines that situate the subject of petrochemical creation and its impact in the Mississippi River corridor. The cumulative impact of Misrach’s photographic approach, combined with the effective and systematic linking of his images to other forms of relevant information by Kate Orff, produces an understanding of environment as not only inextricably linked to human activity and habitation, but which also contains differing agencies constituting a broader ecology. 相似文献
44.
45.
Pei-Chann Chang Jyun-Jie Lin Jui-Chien Hsieh Julia Weng 《Applied Soft Computing》2012,12(10):3165-3175
This study presented a new diagnosis system for myocardial infarction classification by converting multi-lead ECG data into a density model for increasing accuracy and flexibility of diseases detection. In contrast to the traditional approaches, a hybrid system with HMMs and GMMs was employed for data classification. A hybrid approach using multi-leads, i.e., lead-V1, V2, V3 and V4 for myocardial infarction were developed and HMMs were used not only to find the ECG segmentations but also to calculate the log-likelihood value which was treated as statistical feature data of each heartbeat's ECG complex. The 4-dimension feature vector extracted by HMMs was clustered by GMMs with different numbers of distribution (disease and normal data). SVMs classifier was also examined for comparison with our system in experimental result. There were total 1129 samples of heartbeats from clinical data, including 582 data with myocardial infarction and 547 normal data. The sensitivity of this diagnosis system achieved 85.71%, specificity achieved 79.82% and accuracy achieved 82.50% statistically. 相似文献
46.
47.
Tiffany D. Andras Troy S. Alexander Asiri Gahlena R. Mitchell Parry Facundo M. Fernandez Julia Kubanek May D. Wang Mark E. Hay 《Journal of chemical ecology》2012,38(10):1203-1214
Coral reefs are in global decline, with seaweeds increasing as corals decrease. Although seaweeds inhibit coral growth, recruitment, and survivorship, the mechanism of these interactions is poorly understood. Here, we used field experiments to show that contact with four common seaweeds induces bleaching on natural colonies of Porites rus. Controls in contact with inert, plastic mimics of seaweeds did not bleach, suggesting seaweed effects resulted from allelopathy rather than shading, abrasion, or physical contact. Bioassay-guided fractionation of the hydrophobic extract from the red alga Phacelocarpus neurymenioides revealed a previously characterized antibacterial metabolite, neurymenolide A, as the main allelopathic agent. For allelopathy of lipid-soluble metabolites to be effective, the compounds would need to be deployed on algal surfaces where they could transfer to corals on contact. We used desorption electrospray ionization mass spectrometry (DESI-MS) to visualize and quantify neurymenolide A on the surface of P. neurymenioides, and we found the molecule on all surfaces analyzed, with highest concentrations on basal portions of blades. 相似文献
48.
Online social networks became a global phenomenon with enormous social as well as economic impact within a few years. Alone, the most popular online social network, Facebook, counts currently more than 850 million users worldwide. Consequently, online social networks attract a great deal of attention among practitioners as well as researchers. The goal of this article is to provide an overview of online social networks in order to contribute to a better understanding of this worldwide phenomenon. In this context, we address for example the following questions: What are the major functionalities and characteristics of online social networks? What are the users’ motives for using them and how did online social networks emerge and develop over time? What is the impact and value of online social networks from a business perspective and what are corresponding challenges and risks? 相似文献
49.
Leopold Weber Wolfgang Lenhardt Franz Möstl Gregor Götzl Julia Weilbold Heinz Reitner 《BHM Berg- und Hüttenm?nnische Monatshefte》2016,161(4):148-155
Touristic mines are by far not only of public interest. During guided tours the importance of mining and mineral resources for society can be explained in a proper way. Mineral deposits, for long time not accessible and only known from old literature can now be studied in detail by scientists. Old underground mines can be used for different purposes. With respect to Arzberg the different possibilities of utilization of old underground workings are described in detail: A touristic mine serves not only as an attraction, but also as a training centre for underground geological mapping, geochemistry and geophysics research laboratory of universities. For many years the ZAMG (Central Institute for Meteorology and Geodynamics) has been operating a seismic station, and parts of the old mine workings have been used for cheese refinery since 2006. Furthermore, the mine water is utilized for extracting geothermal energy and serves the cooling chambers. The combined use of the old mine workings by different parties permits sharing the substantial maintenance costs. 相似文献
50.