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21.
Tanja Schlaikjær Hartwig Louise Ambye Steen Sørensen Finn Stener Jørgensen 《黑龙江环境通报》2017,37(6):527-539
With a high sensitivity and specificity, non-invasive prenatal testing (NIPT) is an incomparable screening test for fetal aneuploidy. However, the method is rather newly introduced, and experiences with discordant results are few. We did a systematic review of literature reporting details of false positive and false negative NIPT results. Discordant sex chromosome results were not included. We identified 22 studies reporting case details. In total, 206 discordant cases were included, of which 88% were false positive and 12% false negative. Details on maternal age, gestational age, platform/company, Z-score, fetal fraction, results and explanation were specified. The main reasons for discordant results were confined placental mosaicism, maternal copy number variation, vanished twin, maternal cancer and true fetal mosaicism. A very high percentage of cases (67%) were reported with no obvious biological or technical explanation for the discordant result. The included cases represent only a minor part of the true number of false positive or false negative NIPT cases identified in fetal medicine clinics around the world. To ensure knowledge exchange and transparency of NIPT between laboratories, we suggest a systematic recording of discordant NIPT results, as well as a quality assurance by external quality control and accreditation. © 2017 John Wiley & Sons, Ltd. 相似文献
22.
Combining theory and wisdom in pragmatic,scenario-based decision support for sustainable development
Megan Davenport Marion Delport James Nelson Blignaut Tanja Hichert Gerhard van der Burgh 《Journal of Environmental Planning and Management》2019,62(4):692-716
Researchers have increasingly acknowledged the relative strength of ‘hybrid’ approaches to scenario analysis for exploring the futures of coupled human-nature systems. In this paper, we explain, demonstrate, and provisionally evaluate the usefulness of a simple analytical framework, based on five categories of capital assets, as part of a protocol for overcoming the conversion problem in hybrid scenario analysis. Based on a preliminary application of the framework to a case study in South Africa, we suggest that the five capitals framework has the potential to improve expedience and counter the bias against ‘soft’ drivers in hybrid approaches to scenario analysis. However, in light of the methodological trade-off between rigour and expedience, we suggest that future research needs to compare the available protocols for hybrid scenario analysis by weighing up the relative gain in scenario quality versus the relative cost of scenario construction. 相似文献
23.
Bacteria associated with oak and ash on a TCE-contaminated site: characterization of isolates with potential to avoid evapotranspiration of TCE 总被引:1,自引:0,他引:1
Nele Weyens Safiyh Taghavi Tanja Barac Daniel van der Lelie Jana Boulet Tom Artois Robert Carleer Jaco Vangronsveld 《Environmental science and pollution research international》2009,16(7):830-843
Background, aim, and scope
Along transects under a mixed woodland of English Oak (Quercus robur) and Common Ash (Fraxinus excelsior) growing on a trichloroethylene (TCE)-contaminated groundwater plume, sharp decreases in TCE concentrations were observed, while transects outside the planted area did not show this remarkable decrease. This suggested a possibly active role of the trees and their associated bacteria in the remediation process. Therefore, the cultivable bacterial communities associated with both tree species growing on this TCE-contaminated groundwater plume were investigated in order to assess the possibilities and practical aspects of using these common native tree species and their associated bacteria for phytoremediation. In this study, only the cultivable bacteria were characterized because the final aim was to isolate TCE-degrading, heavy metal resistant bacteria that might be used as traceable inocula to enhance bioremediation. 相似文献24.
Cytotoxicity of TBBPA and effects on proliferation, cell cycle and MAPK pathways in mammalian cells 总被引:4,自引:0,他引:4
Poly-brominated flame retardants are ecotoxicologically relevant chemicals that can show high persistency in environmental samples and bioaccumulation in marine and fresh water animals. One of the most widely used compound is tetrabromobisphenol A (TBBPA). Until today, the toxicological data are rather fragmentary. Our studies on acute and sub-acute toxic effects with established cell lines demonstrate that TBBPA interferes with cellular signaling pathways. Cell viability is significantly reduced in a time- and concentration-dependent manner. The observed EC50 for rat kidney cells (NRK) was 52 microM (27 mg/l), 168 microM (90 mg/l) for A549 human lung cells, and 200 microM (108 mg/l) for Cal-62 human thyroid cells, respectively. The comparison of TBBPA with the non-brominated substance bisphenol A (BPA) clearly demonstrates that only the brominated compound exerts these effects on proliferation and cell viability. Cell cycle regulation was influenced considerably in Cal-62 cells, showing an explicit G2/M arrest in the cell cycle at TBBPA concentrations higher than 75 microM. Cellular signaling pathways directly connected to these affected parameters, e.g. the mitogen activated protein kinase (MAPK) cascades, are partly influenced in a cell specific and dose dependent manner. The extracellular-signal regulated kinase (ERK) is deactivated in NRK and A549 cells and activated in Cal-62 cells with increasing TBBPA concentrations. 相似文献
25.
Melita Mihaljević Dubravka Špoljarić Filip Stević Tanja Žuna Pfeiffer 《Environmental monitoring and assessment》2013,185(10):8601-8619
In this research, we aimed to find out how the differences in hydrological connectivity between the main river channel and adjacent floodplain influence the changes in phytoplankton community structure along a river–floodplain system. The research was performed in the River Danube floodplain (Croatian river section) in the period 2008–2009 characterised by different flooding pattern on an annual time scale. By utilising the morpho-functional approach and multivariate analyses, the flood-derived structural changes of phytoplankton were analysed. The lake stability during the isolation phase triggered the specific pattern of morpho-functional groups (MFG) which were characterised by cyanobacterial species achieving very high biomass. Adversely, the high water turbulence in the lake during the frequent and extreme flooding led to evident similarity between lake and river assemblages. Besides different diatom species (groups of small and large centrics and pennates), which are the most abundant representatives in the river phytoplankton, many other groups such as cryptophytes and colonial phytomonads appeared to indicate altered conditions in the floodplain driven by flooding. Having different functional properties, small centric diatom taxa sorted to only one MFG cannot clearly reflect environmental changes that are shown by the species-level pattern. Disadvantages in using the MFG approach highlight that it is still necessary to combine it with taxonomical approach in monitoring of phytoplankton in the river–floodplain ecosystems. 相似文献
26.
Rüdiger Riesch Virginia Duwe Nina Herrmann Lisa Padur Annemarie Ramm Kristin Scharnweber Matthias Schulte Tanja Schulz-Mirbach Madlen Ziege Martin Plath 《Behavioral ecology and sociobiology》2009,63(10):1515-1526
One potential trade-off that bold individuals face is between increased predation risks and gains in resources. Individuals
experiencing high predation and hungry individuals (or individuals with low body condition) are predicted to show increased
boldness. We examined one behavioral trait previously reported to be associated with boldness (the time individual fish needed
to emerge from shelter) in various populations of mollies (Poecilia spp.). Our study system included several southern Mexican surface streams with high piscine predation and high food availability,
sulfidic surface streams with high avian predation, in which the inhabiting fish show reduced body condition, and a sulfidic
cave, where predation and body condition are low. Our comparison revealed very short times to emerge from the start box in
populations from non-sulfidic streams. In sulfidic habitats (whether surface or cave), it took individual Poecilia mexicana considerably longer to emerge from the start box, and the same difference was also found in an independent comparison between
P. mexicana and the closely related, highly sulfide-adapted Poecilia sulphuraria. Fish reared under common garden conditions (in the absence of predators and hydrogen sulfide) showed intermediate boldness
scores to the extremes observed in the field. Our data thus indicate that (a) boldness is shaped by environmental conditions/experiential
effects, but is not heritable, (b) predation affects boldness in the predicted direction, but (c) low body condition leads
to reduced boldness. Extremophile Poecilia spp. spend most of their time surfacing to survive under sulfidic and hypoxic conditions, which exposes them to increased
levels of predations, but the fish forage on the bottom. Hence, in this system, increased boldness does not increase foraging
success. We argue that energy limitation favors reducing energetically costly behaviors, and exploring novel environments
may be just one of them. 相似文献
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28.
Tanja Stanić Aleksandra Daković Aleksandar Živanović Magdalena Tomašević-Čanović Vera Dondur Sonja Milićević 《Environmental Chemistry Letters》2009,7(2):161-166
Adsorption of arsenic (V) by natural zeolitic tuff, modified with iron (III), was investigated. Also, the iron (III) adsorption
characteristics by natural zeolitic tuff was evaluated. It was determined that iron (III) adsorption by starting zeolitic
tuff was best represented by the Freundlich type of isotherm, having correlation coefficient (r
2) of 0.990. Arsenic (V) adsorption by iron (III)-modified zeolitic tuff followed a nonlinear type of isotherm. The best fit
of the experimental data was obtained using the Langmuir–Freundlich model (r
2 = 0.99), with the estimated maximum of arsenic (V) adsorption to iron (III)-modified zeolitic tuff of 1.55 mg/g. 相似文献
29.
Kost C Lakatos T Böttcher I Arendholz WR Redenbach M Wirth R 《Die Naturwissenschaften》2007,94(10):821-828
Fungus-growing ants and their fungal cultivar form a highly evolved mutualism that is negatively affected by the specialized
parasitic fungus Escovopsis. Filamentous Pseudonocardia bacteria occurring on the cuticle of attine ants have been proposed to form a mutualistic interaction with these ants in
which they are vertically transmitted (i.e. from parent to offspring colonies). Given a strictly vertical transmission of
Pseudonocardia, the evolutionary theory predicts a reduced genetic variability of symbionts among ant lineages. The aim of this study was
to verify whether actinomycetes, which occur on Acromyrmex octospinosus leaf-cutting ants, meet this expectation by comparing their genotypic variability with restriction fragment length polymorphisms.
Multiple actinomycete strains could be isolated from both individual ant workers and colonies (one to seven strains per colony).
The colony specificity of actinomycete communities was high: Only 15% of all strains were isolated from more than one colony,
and just 5% were present in both populations investigated. Partial sequencing of 16S ribosomal deoxyribonucleic acid of two
of the isolated strains assigned both of them to the genus Streptomyces. Actinomycetes could also be isolated from workers of the two non-attine ant species Myrmica rugulosa and Lasius flavus. Sixty-two percent of the strains derived from attine ants and 80% of the strains isolated from non-attine ants inhibited
the growth of Escovopsis. Our data suggest that the association between attine ants and their actinomycete symbionts is less specific then previously
thought. Soil-dwelling actinomycetes may have been dynamically recruited from the environment (horizontal transmission), probably
reflecting an adaptation to a diverse community of microbial pathogens. 相似文献
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