42 research outputs found

    NMR-based metabolomic profiling of overweight adolescents:an elucidation of the effects of inter-/intraindividual differences, gender, and pubertal development

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    The plasma and urine metabolome of 192 overweight 12–15-year-old adolescents (BMI of 25.4 ± 2.3 kg/m2) were examined in order to elucidate gender, pubertal development measured as Tanner stage, physical activity measured as number of steps taken daily, and intra-/interindividual differences affecting the metabolome detected by proton NMR spectroscopy. Higher urinary excretion of citrate, creatinine, hippurate, and phenylacetylglutamine and higher plasma level of phosphatidylcholine and unsaturated lipid were found for girls compared with boys. The results suggest that gender differences in the metabolome are being commenced already in childhood. The relationship between Tanner stage and the metabolome showed that pubertal development stage was positively related to urinary creatinine excretion and negatively related to urinary citrate content. No relations between physical activity and the metabolome could be identified. The present study for the first time provides comprehensive information about associations between the metabolome and gender, pubertal development, and physical activity in overweight adolescents, which is an important subject group to approach in the prevention of obesity and life-style related diseases. While this study is preliminary, these results may have the potential to translate into clinical applicability upon further investigations; if biomarkers for Tanner stage can be established, these might be used for identification of individuals susceptible to an early pubertal development

    Poison, plants and Palaeolithic hunters. An analytical method to investigate the presence of plant poison on archaeological artefacts

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    In this paper we present the development of a method for the detection of toxic substances on ancient arrow points. The aim is to go back in time until the Palaeolithic period in order to determine if poisonous substances were used to enhance the hunting weapons. The ethnographic documentation demonstrates that hunters of every latitude poisoned their weapons with toxic substances derived from plants and occasionally from animals. This highlights that often the weapons would be rather ineffective if the tips were not poisoned. The fact that toxic substances were available and the benefits arising from their application on throwing weapons, suggests that this practice could be widespread also among prehistoric hunters. The project reviewed the research of the toxic molecules starting from current information on modern plants and working backwards through the ages with the study of ethnographic and historical weapons. This knowledge was then applied to the archaeological material collected from International museum collections. Results have shown that using this method it is possible to detect traces of toxic molecules with mass spectrometry (MS) and hyphenated chromatographic techniques even on samples older than one hundred years, which we consider a positive incentive to continue studying plant poisons on ancient hunting tools

    Stable oxygen isotope variability in two contrasting glacier river catchments in Greenland

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    Analysis of stable oxygen isotope (δ18O) characteristics is a useful tool to investigate water provenance in glacier river systems. In order to attain knowledge on the diversity of δ18O variations in Greenlandic rivers, we examined two contrasting glacierised catchments disconnected from the Greenland Ice Sheet (GrIS). At the Mittivakkat Gletscher river, a small river draining a local temperate glacier in southeast Greenland, diurnal oscillations in δ18O occurred with a 3 h time lag to the diurnal oscillations in run-off. The mean annual δ18O was −14.68 ± 0.18 ‰ during the peak flow period. A hydrograph separation analysis revealed that the ice melt component constituted 82 ± 5 % of the total run-off and dominated the observed variations during peak flow in August 2004. The snowmelt component peaked between 10:00 and 13:00 local time, reflecting the long travel time and an inefficient distributed subglacial drainage network in the upper part of the glacier. At the Kuannersuit Glacier river on the island Qeqertarsuaq in west Greenland, the δ18O characteristics were examined after the major 1995–1998 glacier surge event. The mean annual δ18O was −19.47 ± 0.55 ‰. Despite large spatial variations in the δ18O values of glacier ice on the newly formed glacier tongue, there were no diurnal oscillations in the bulk meltwater emanating from the glacier in the post-surge years. This is likely a consequence of a tortuous subglacial drainage system consisting of linked cavities, which formed during the surge event. Overall, a comparison of the δ18O compositions from glacial river water in Greenland shows distinct differences between water draining local glaciers and ice caps (between −23.0 and −13.7 ‰) and the GrIS (between −29.9 and −23.2 ‰). This study demonstrates that water isotope analyses can be used to obtain important information on water sources and the subglacial drainage system structure that is highly desired for understanding glacier hydrology

    Ice-dammed lake and ice-margin evolution during the Holocene in the Kangerlussuaq area of west Greenland

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    There is a lack of detailed information on the Holocene evolution of the west Greenland ice margin, not least because it was farther inland than at present and thus at present is covered by ice. Suggestions have been put forward, both of relatively quick ice-margin retreat and of relatively stable ice-margin positions. This study presents the first exploitation of sediments from an ice-dammed basin. Sediment that is rich in organic material records a period of time sufficient for vegetation to thrive; thus, without a lake and with a distal and diminished ice mass relative to the present. In contrast, sediment composed of suspension-settling deposits and with drop stones records an ice-dammed lake and a proximal calving ice-margin. Overall, we evidence relatively coarse-grained glacifluvial sedimentation predominantly from an ice-marginal delta and/or a proglacial, braided river soon after the early Holocene deglaciation of this area. Subsequent mid-Holocene aeolian activity deposited leaves, some vegetation (roots) developed in the basin, and ponding of water formed organic-rich “gyttja” sediments and thin layers of peat. The lake then became ice marginal, and ice advances are interpreted to have occurred at approximately 4000 cal. yr BP, and between 2776 ± 26 cal. yr BP and 2440 ± 45 cal. yr BP. The Little Ice Age ice-margin advance at Russell Glacier apparently reached its maximum extent after 147 ± 39 cal. yr BP, whereas at Isunnguata Sermia the maximum could have been as early as 245 ± 26 cal. yr BP. Given that ice-marginal lakes are becoming globally ubiquitous, improved resolution and new geological data on lake and ice-margin dynamics and interactions, such as ice-dammed lake-basin sediments, will be important for numerical models for assessing past and future ice-mass evolution

    Progress and challenges in glacial lake outburst flood research (2017–2021):a research community perspective

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    Glacial lake outburst floods (GLOFs) are among the most concerning consequences of retreating glaciers in mountain ranges worldwide. GLOFs have attracted significant attention amongst scientists and practitioners in the past 2 decades, with particular interest in the physical drivers and mechanisms of GLOF hazard and in socioeconomic and other human-related developments that affect vulnerabilities to GLOF events. This increased research focus on GLOFs is reflected in the gradually increasing number of papers published annually. This study offers an overview of recent GLOF research by analysing 594 peer-reviewed GLOF studies published between 2017 and 2021 (Web of Science and Scopus databases), reviewing the content and geographical focus as well as other characteristics of GLOF studies. This review is complemented with perspectives from the first GLOF conference (7-9 July 2021, online) where a global GLOF research community of major mountain regions gathered to discuss the current state of the art of integrated GLOF research. Therefore, representatives from 17 countries identified and elaborated trends and challenges and proposed possible ways forward to navigate future GLOF research, in four thematic areas: (i) understanding GLOFs - timing and processes; (ii) modelling GLOFs and GLOF process chains; (iii) GLOF risk management, prevention and warning; and (iv) human dimensions of GLOFs and GLOF attribution to climate change.Fil: Emmer, Adam. University of Graz; AustriaFil: Allen, Simon K.. Universitat Zurich; Suiza. Universidad de Ginebra; SuizaFil: Carey, Mark. University of Oregon; Estados UnidosFil: Frey, Holger. Universitat Zurich; SuizaFil: Huggel, Christian. Universitat Zurich; SuizaFil: Korup, Oliver. Universitat Potsdam; AlemaniaFil: Mergili, Martin. University of Graz; AustriaFil: Sattar, Ashim. Universitat Zurich; SuizaFil: Veh, Georg. Universitat Potsdam; AlemaniaFil: Chen, Thomas Y.. Columbia University; Estados UnidosFil: Cook, Simon J.. University Of Dundee; Reino Unido. Unesco. Centre For Water Law, Policy And Science; Reino UnidoFil: Correas Gonzalez, Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; ArgentinaFil: Das, Soumik. Jawaharlal Nehru University; IndiaFil: Diaz Moreno, Alejandro. Reynolds International Ltd; Reino UnidoFil: Drenkhan, Fabian. Pontificia Universidad Católica de Perú; PerúFil: Fischer, Melanie. Universitat Potsdam; AlemaniaFil: Immerzeel, Walter W.. Utrecht University; Países BajosFil: Izagirre, Eñaut. Universidad del País Vasco; EspañaFil: Joshi, Ramesh Chandra. Kumaun University India; IndiaFil: Kougkoulos, Ioannis. American College Of Greece; GreciaFil: Kuyakanon Knapp, Riamsara. University of Oslo; Noruega. University of Cambridge; Estados UnidosFil: Li, Dongfeng. National University Of Singapore; SingapurFil: Majeed, Ulfat. University Of Kashmir; IndiaFil: Matti, Stephanie. Haskoli Islands; IslandiaFil: Moulton, Holly. University of Oregon; Estados UnidosFil: Nick, Faezeh. Utrecht University; Países BajosFil: Piroton, Valentine. Université de Liège; BélgicaFil: Rashid, Irfan. University Of Kashmir; IndiaFil: Reza, Masoom. Kumaun University India; IndiaFil: Ribeiro De Figueiredo, Anderson. Universidade Federal do Rio Grande do Sul; BrasilFil: Riveros, Christian. Instituto Nacional de Investigación En Glaciares y Ecosistemas de Montaña; PerúFil: Shrestha, Finu. International Centre For Integrated Mountain Development Nepal; NepalFil: Shrestha, Milan. Arizona State University; Estados UnidosFil: Steiner, Jakob. International Centre For Integrated Mountain Development Nepal; NepalFil: Walker-Crawford, Noah. Colegio Universitario de Londres; Reino UnidoFil: Wood, Joanne L.. University of Exeter; Reino UnidoFil: Yde, Jacob C.. Western Norway University Of Applied Sciences; Suiz

    An Integrated Bioinformatics Approach Identifies Elevated Cyclin E2 Expression and E2F Activity as Distinct Features of Tamoxifen Resistant Breast Tumors

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    Approximately half of estrogen receptor (ER) positive breast tumors will fail to respond to endocrine therapy. Here we used an integrative bioinformatics approach to analyze three gene expression profiling data sets from breast tumors in an attempt to uncover underlying mechanisms contributing to the development of resistance and potential therapeutic strategies to counteract these mechanisms. Genes that are differentially expressed in tamoxifen resistant vs. sensitive breast tumors were identified from three different publically available microarray datasets. These differentially expressed (DE) genes were analyzed using gene function and gene set enrichment and examined in intrinsic subtypes of breast tumors. The Connectivity Map analysis was utilized to link gene expression profiles of tamoxifen resistant tumors to small molecules and validation studies were carried out in a tamoxifen resistant cell line. Despite little overlap in genes that are differentially expressed in tamoxifen resistant vs. sensitive tumors, a high degree of functional similarity was observed among the three datasets. Tamoxifen resistant tumors displayed enriched expression of genes related to cell cycle and proliferation, as well as elevated activity of E2F transcription factors, and were highly correlated with a Luminal intrinsic subtype. A number of small molecules, including phenothiazines, were found that induced a gene signature in breast cancer cell lines opposite to that found in tamoxifen resistant vs. sensitive tumors and the ability of phenothiazines to down-regulate cyclin E2 and inhibit proliferation of tamoxifen resistant breast cancer cells was validated. Our findings demonstrate that an integrated bioinformatics approach to analyze gene expression profiles from multiple breast tumor datasets can identify important biological pathways and potentially novel therapeutic options for tamoxifen-resistant breast cancers

    Fauna Europaea: Diptera -Brachycera

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    Link to publication Citation for published version (APA): Pape, T., Beuk, P., Pont, A. C., Shatalkin, A. I., Ozerov, A. L., Woźnica, A. J., ... de Jong, Y. (2015). Fauna Europaea: 3, [e4187]. https://doi.org/10.3897/BDJ.3.e4187 General rights It is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like Creative Commons). Disclaimer/Complaints regulations If you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: https://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible. Abstract Fauna Europaea provides a public web-service with an index of scientific names (including important synonyms) of all extant multicellular European terrestrial and freshwater animals and their geographical distribution at the level of countries and major islands (east of the Urals and excluding the Caucasus region). The Fauna Europaea project comprises about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies, which is much more than the originally projected number of 100,000 species. Fauna Europaea represents a huge effort by more than 400 contributing taxonomic specialists throughout Europe and is a unique (standard) reference suitable for many user communities in science, government, industry, nature conservation and education. The Diptera-Brachycera is one of the 58 Fauna Europaea major taxonomic groups, and data have been compiled by a network of 55 specialists. Within the two-winged insects (Diptera), the Brachycera constitute a monophyletic group, which is generally given rank of suborder. The Brachycera may be classified into the probably paraphyletic 'lower brachyceran grade' and the monophyletic Eremoneura. The latter contains the Empidoidea, the Apystomyioidea with a single Nearctic species, and the Cyclorrhapha, which in turn is divided into the paraphyletic 'aschizan grade' and the monophyletic Schizophora. The latter is traditionally divided into the paraphyletic 'acalyptrate grade' and the monophyletic Calyptratae. Our knowledge of the European fauna of Diptera-Brachycera varies tremendously among families, from the reasonably well known hoverflies (Syrphidae) to the extremely poorly known scuttle flies (Phoridae). There has been a steady growth in our knowledge of European Diptera for the last two centuries, with no apparent slow down, but there is a shift towards a larger fraction of the new species being found among the families of the nematoceran grade (lower Diptera), which due to a larger number of small-sized species may be considered as taxonomically more challenging. Most of Europe is highly industrialised and has a high human population density, and the more fertile habitats are extensively cultivated. This has undoubtedly increased the extinction risk for numerous species of brachyceran flies, yet with the recent re-discovery of Thyreophora cynophila (Panzer), there are no known cases of extinction at a European level. However, few national Red Lists have extensive information on Diptera. For the Diptera-Brachycera, data from 96 families containing 11,751 species are included in this paper

    Body mass index and musculoskeletal pain: is there a connection?

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