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The use of computational tools to identify biological targets of natural products with anticancer properties and unknown modes of action is gaining momentum. We employed self-organizing maps to deconvolute the phenotypic effects of piperlongumine (PL) and establish a link to modulation of the human transient receptor potential vanilloid 2 (hTRPV2) channel. The structure of the PL-bound full-length rat TRPV2 channel was determined by cryo-EM. PL binds to a transient allosteric pocket responsible for a new mode of anticancer activity against glioblastoma (GBM) in which hTRPV2 is overexpressed. Calcium imaging experiments revealed the importance of Arg539 and Thr522 residues on the antagonistic effect of PL and calcium influx modulation of the TRPV2 channel. Downregulation of hTRPV2 reduces sensitivity to PL and decreases ROS production. Analysis of GBM patient samples associates hTRPV2 overexpression with tumor grade, disease progression, and poor prognosis. Extensive tumor abrogation and long term survival was achieved in two murine models of orthotopic GBM by formulating PL in an implantable scaffold/hydrogel for sustained local therapy. Furthermore, in primary tumor samples derived from GBM patients, we observed a selective reduction of malignant cells in response to PL ex vivo. Our results establish a broadly applicable strategy, leveraging data-motivated research hypotheses for the discovery of novel means tackling cancer.

AimsThough formalin remains to be the gold standard fixative in pathology departments, analytical challenges persist for nucleic acid evaluations. In our laboratory, formalin fixation of skin samples in particular impairs diagnostic accuracy and demands repetition of biopsies and analytical procedures. PAXgene Tissue Systems may be an alternative; however, according to manufacturer specifications it only allows fixation for 48 hours before having to add a stabiliser. This may be a challenge in laboratories, which are closed in weekends and bank holidays. Our aim was to validate this alternative fixative for dermatological samples with prolonged fixation times using standard laboratory protocols developed for formalin-fixed specimens. We compared the results with gold standard formalin fixation.MethodsSkin specimens were formalin or PAXgene fixed for either 2 hours, 24 hours, 3 days or 7 days, paraffin-embedded, analysed and scored by observers.ResultsGenerally, formalin outperformed PAXgene fixation in H&E stains and fluorescence in situ hybridisation (FISH), but both seem usable for diagnostics. Time of PAXgene fixation did not have an impact on alcian blue-Van Gieson (ABVG), H&E (p=0.48), nor immunohistochemistry (p=0.74). There was a tendency towards best PAXgene performance at 24 hours of fixation for FISH, and for DNA integrity analysis 24 hours or 3 days.ConclusionsProlonging PAXgene fixation time to 3 days before adding stabiliser does not seem to have major impact on performance of general diagnostic analysis, but our preliminary results show optimisation of internal protocols are needed. PAXgene is an expensive alternative and may be confined to some dermatological samples.

The main goals of this study were to understand the different roles played by teachers and students during a school-guided tour to an aquarium and to analyse their different perspectives about the visit. The study focused on students’ and teachers’ behaviour during school-guided visits to an aquarium; students’ and teachers’ perspectives about this type of school visits; and the reasons provided by teachers to engage in a guided tour to a science museum. Direct observations of 39 guided tours were performed in order to describe the structure of the visit and the participants’ behaviour. A questionnaire was given to 145 teachers and 191 students after the visit, in order to describe their perspectives about the visit, and an online questionnaire was sent to a sample of 11 teachers, in order to understand their ideas about school visits to science museums. Data analysis showed that the guided visits, although well evaluated by both students and teachers, were mainly guide-directed and lecture-oriented, giving students and teachers very little choice and control over the learning agenda. Moreover, teachers showed a very passive role during the visit and reported limited plans for preparation and follow-up activities that would support the visit. Despite this scenario, the teachers who were questioned preferred guided visits to non-guided visits and recognized the potential of museums for learning. The possible role of teachers in establishing the necessary connection between guided tours and school science, and helping to bridge school curriculum, museum content, and student inquiries is discussed.

AbstractGlucocorticoids (GC) play an important role in physiologic and pathophysiologic adaptive responses to stress. The majority of these effects are mediated by the GC receptors (GR). GC sensitivity largely depends of the amount of available GR, and their ability to bind the GC-responsive element and/or other nuclear transcription factors, leading to modulation of the expression of GC target genes. Clinical conditions of tissue-specific GC resistance or GC hypersensitivity have been described in several diseases, such as chronic inflammatory and autoimmune conditions, and in visceral obesity, such as metabolic syndrome. Several in vivo and in vitro methods have been described, allowing the evaluation and quantitation of GC sensitivity. The recognition of these parameters has improved our comprehension of the mechanisms involved in those diseases, with potential implications for the diagnosis and therapy of such abnormalities.Copyright © 2009 S. Karger AG, Basel

AbstractBackground/Aims:The wide variability of responses to corticotherapy suggests a role for individual recognition of steroid sensitivity in order to customize treatment. Oral dexamethasone (DEX) administration may be hindered by the rate of its intestinal absorption and the liver first-passage effect. In this study we suggest that an intravenous very low dose DEX suppression test (VLD IV-DST) can be used as an index for glucocorticoid (GC) sensitivity. Methods:We evaluated 87 normal subjects: 44 prepubertal children, 23 adolescents and 20 adults with a VLD IV-DST using 20 μg/m2of DEX (dose able to recognize GC sensitivity). Cortisol was initially measured at several time-points after DEX prompting us to establish its nadir and subsequent simplification of the test by measuring cortisol at baseline and after 120 min. Results:Baseline cortisol was similar in adolescents and in adults, but lower in children. There was a spectrum of individual responses in all age groups. The percent reduction of cortisol after 120 min was different in these three age groups, with median values of 44.4 in children, 25.9 in adolescents and 61.6 in adults. Conclusion:This simplified VLD IV-DST using 20 μg/m2of DEX is useful to evaluate individual sensitivity to GC in different age groups.Copyright © 2008 S. Karger AG, Basel

Abstract In this paper we review the temporal patterns of variation of rocky intertidal resident fish assemblages and discuss possible mechanisms that may explain these patterns. These assemblages tend to be highly resilient and stable on an inter-annual basis, but tend to undergo marked seasonal fluctuations, as different species recruit and reach different phases of their life cycles. Larval supply is usually not a limiting factor suggesting that post-recruitment deterministic mechanisms exert a strong influence on assemblage organization. At methodological level, it is argued that traditional destructive sampling techniques should be avoided whenever possible. It is proposed that a deeper understanding of these assemblages requires more detailed information on intraspecific interactions between members of each constituent species, and information on the interactions between limited numbers of species for which mutually influences are particularly strong. It is argued that size, topography and biotic cover of a pool may provide a limited number of favourable sites for fishes of a given species and class size so that intraspecific competition, and possibly predation of the individuals less able to get access to best sites, may explain to a considerable extent the inter-annual stability and resilience of these assemblages.