1,181 research outputs found
Silicon fractionation in Mollic Fluvisols along the Central Elbe River, Germany
Quantification of Si in its different forms in soil is a prerequisite to understand the geochemical distribution and fate of Si along with their driving biogeochemical processes. However, different Si fractions in floodplain soils have not been quantified yet, and little is known about the processes driving Si fractionation in these soils. The aim of this study was to clarify the processes that drive formation and distribution of Si among fractions in floodplain soils. We obtained and quantified these fractions using a sequential Si extraction method (Georgiadis et al., 2013) in three Mollic Fluvisols along the Central Elbe River. The highest Si proportion apart from the residual fraction was found in minerogenic amorphous silica (up to 5.6% of total Si), followed by Si occluded in pedogenic oxides and hydroxides (up to 0.7% of total Si). Silicon from biogenic amorphous silica amounted to 0.02-0.6% of total Si. The smallest proportion of Si was found in the mobile Si fraction and made up about 0.01% of the total Si. The results of this study demonstrate the importance of the soil water budget on the accumulation of easy-to-mobilise Si, Si occluded in pedogenic oxides and hydroxides and amorphous silica. Reductive dissolution of Fe and Mn oxides may induce Si release into the soil solution, subsequent oxidizing conditions may induce Si accumulation by adsorption, co-precipitation and occlusion of Si on/with newly formed Fe and Mn oxides. Accumulation of bio-opal after flooding may induce larger amounts of biogenic amorphous silica in floodplain soils than in terrestrial soils. Finally, floodplain soils may accumulate larger amounts of Si bound to occluded particulate SOM than terrestrial soils, which experience less input of particulate SOM than floodplain soils
The evolution of Runx genes I. A comparative study of sequences from phylogenetically diverse model organisms
BACKGROUND: Runx genes encode proteins defined by the highly conserved Runt DNA-binding domain. Studies of Runx genes and proteins in model organisms indicate that they are key transcriptional regulators of animal development. However, little is known about Runx gene evolution. RESULTS: A phylogenetically broad sampling of publicly available Runx gene sequences was collected. In addition to the published sequences from mouse, sea urchin, Drosophila melanogaster and Caenorhabditis elegans, we collected several previously uncharacterised Runx sequences from public genome sequence databases. Among deuterostomes, mouse and pufferfish each contain three Runx genes, while the tunicate Ciona intestinalis and the sea urchin Strongylocentrotus purpuratus were each found to have only one Runx gene. Among protostomes, C. elegans has a single Runx gene, while Anopheles gambiae has three and D. melanogaster has four, including two genes that have not been previously described. Comparative sequence analysis reveals two highly conserved introns, one within and one just downstream of the Runt domain. All vertebrate Runx genes utilize two alternative promoters. CONCLUSIONS: In the current public sequence database, the Runt domain is found only in bilaterians, suggesting that it may be a metazoan invention. Bilaterians appear to ancestrally contain a single Runx gene, suggesting that the multiple Runx genes in vertebrates and insects arose by independent duplication events within those respective lineages. At least two introns were present in the primordial bilaterian Runx gene. Alternative promoter usage arose prior to the duplication events that gave rise to three Runx genes in vertebrates
Awakening the sleeping giant of urban green in times of crisis—coverage, co-creation and practical guidelines for optimizing biodiversity-friendly and health-promoting residential greenery
As multiple crises deepen existing inequalities in urban societies within and between neighborhoods, strategically integrating nature-based solutions into the living environment can help reduce negative impacts and improve public health, social cohesion, and well-being. Compared to public green such as parks, semi-public residential greenery is rarely studied, is regularly overlooked by planners, and often receives step-motherly treatment from architects and housing companies. We approximated the area of residential greenery of modernist multi-story apartment complexes in Berlin, Germany. We surveyed residents’ suggestions for improving their living environments in vulnerable neighborhoods, report on co-creation experiences, and provide a practical guideline for optimizing health-promoting residential green spaces. The semi-public open space on the doorstep of two-thirds of Berlin’s population is highly fragmented and, in total, has a similar area as the public green spaces and a great potential for qualitative development. Just as the suitability of different nature-based solutions to be integrated into the residential greenery depends on building types, resident demands differ between neighborhoods. Residents called for more involvement in design, implementation, and maintenance, frequently proposing that biodiversity-friendly measures be included. As there is no universal solution even for neighborhoods sharing similar structural and socioeconomic parameters, we propose, and have tested, an optimization loop for health-promoting residential greening that involves exploring residents’ needs and co-creating local solutions for urban regeneration processes that can be initiated by different actors using bottom-up and/or top-down approaches in order to unlock this potential for healthy, livable and biodiversity friendly cities.Peer Reviewe
Awakening the sleeping giant of urban green in times of crisis—coverage, co-creation and practical guidelines for optimizing biodiversity-friendly and health-promoting residential greenery
As multiple crises deepen existing inequalities in urban societies within and between neighborhoods, strategically integrating nature-based solutions into the living environment can help reduce negative impacts and improve public health, social cohesion, and well-being. Compared to public green such as parks, semi-public residential greenery is rarely studied, is regularly overlooked by planners, and often receives step-motherly treatment from architects and housing companies. We approximated the area of residential greenery of modernist multi-story apartment complexes in Berlin, Germany. We surveyed residents’ suggestions for improving their living environments in vulnerable neighborhoods, report on co-creation experiences, and provide a practical guideline for optimizing health-promoting residential green spaces. The semi-public open space on the doorstep of two-thirds of Berlin’s population is highly fragmented and, in total, has a similar area as the public green spaces and a great potential for qualitative development. Just as the suitability of different nature-based solutions to be integrated into the residential greenery depends on building types, resident demands differ between neighborhoods. Residents called for more involvement in design, implementation, and maintenance, frequently proposing that biodiversity-friendly measures be included. As there is no universal solution even for neighborhoods sharing similar structural and socioeconomic parameters, we propose, and have tested, an optimization loop for health-promoting residential greening that involves exploring residents’ needs and co-creating local solutions for urban regeneration processes that can be initiated by different actors using bottom-up and/or top-down approaches in order to unlock this potential for healthy, livable and biodiversity friendly cities
Albatrellus confluens (Alb. & Schwein.) Kotl. & Pouz.: natural fungal compounds and synthetic derivatives with in vitro anthelmintic activities and antiproliferative effects against two human cancer cell lines
Neglected tropical diseases affect the world's poorest populations with soil-transmitted helminthiasis and schistosomiasis being among the most prevalent ones. Mass drug administration is currently the most important control measure, but the use of the few available drugs is giving rise to increased resistance of the parasites to the drugs. Different approaches are needed to come up with new therapeutic agents against these helminths. Fungi are a source of secondary metabolites, but most fungi remain largely uninvestigated as anthelmintics. In this report, the anthelmintic activity of Albatrellus confluens against Caenorhabditis elegans was investigated using bio-assay guided isolation. Grifolin (1) and neogrifolin (2) were identified as responsible for the anthelmintic activity. Derivatives 4-6 were synthesized to investigate the effect of varying the prenyl chain length on anthelmintic activity. The isolated compounds 1 and 2 and synthetic derivatives 4-6, as well as their educts 7-10, were tested against Schistosoma mansoni (adult and newly transformed schistosomula), Strongyloides ratti, Heligmosomoides polygyrus, Necator americanus, and Ancylostoma ceylanicum. Prenyl-2-orcinol (4) and geranylgeranyl-2-orcinol (6) showed promising activity against newly transformed schistosomula. The compounds 1, 2, 4, 5, and 6 were also screened for antiproliferative or cytotoxic activity against two human cancer lines, viz. prostate adenocarcinoma cells (PC-3) and colorectal adenocarcinoma cells (HT-29). Compound 6 was determined to be the most effective against both cell lines with IC50 values of 16.1 microM in PC-3 prostate cells and 33.7 microM in HT-29 colorectal cells
Mutual Zonated Interactions of Wnt and Hh Signaling Are Orchestrating the Metabolism of the Adult Liver in Mice and Human
The Hedgehog (Hh) and Wnt/β-Catenin (Wnt) cascades are morphogen pathways whose pronounced influence on adult liver metabolism has been identified in recent years. How both pathways communicate and control liver metabolic functions are largely unknown. Detecting core components of Wnt and Hh signaling and mathematical modeling showed that both pathways in healthy liver act largely complementary to each other in the pericentral (Wnt) and the periportal zone (Hh) and communicate mainly by mutual repression. The Wnt/Hh module inversely controls the spatiotemporal operation of various liver metabolic pathways, as revealed by transcriptome, proteome, and metabolome analyses. Shifting the balance to Wnt (activation) or Hh (inhibition) causes pericentralization and periportalization of liver functions, respectively. Thus, homeostasis of the Wnt/Hh module is essential for maintaining proper liver metabolism and to avoid the development of certain metabolic diseases. With caution due to minor species-specific differences, these conclusions may hold for human liver as well
A rare case of sudden blindness due to a pituitary adenoma coincidentally infected with methicillin-resistant Staphylococcus aureus (MRSA)
Aspirin and NSAID use and lung cancer risk: a pooled analysis in the International Lung Cancer Consortium (ILCCO)
Purpose: To investigate the hypothesis that non-steroidal anti-inflammatory drugs (NSAIDs) lower lung cancer risk. Methods: We analysed pooled individual-level data from seven case-control and one cohort study in the International Lung Cancer Consortium (ILCCO). Relative risks for lung cancer associated with self-reported history of aspirin and other NSAID use were estimated within individual studies using logistic regression or proportional hazards models, adjusted for packyears of smoking, age, calendar period, ethnicity and education and were combined using random effects meta-analysis. Results: A total of 4,309 lung cancer cases (mean age at diagnosis 65 years, 45% adenocarcinoma and 22% squamous-cell carcinoma) and 58,301 non-cases/controls were included. Amongst controls, 34% had used NSAIDs in the past (81% of them used aspirin). After adjustment for negative confounding by smoking, ever-NSAID use (affirmative answer to the study-specific question on NSAID use) was associated with a 26% reduction (95% confidence interval 8 to 41%) in lung cancer risk in men, but not in women (3% increase (-11% to 30%)). In men, the association was stronger in current and former smokers, and for squamous-cell carcinoma than for adenocarcinomas, but there was no trend with duration of use. No differences were found in the effects on lung cancer risk of aspirin and non-aspirin NSAIDs. Conclusions Evidence from ILCCO suggests that NSAID use in men confers a modest protection for lung cancer, especially amongst ever-smokers. Additional investigation is needed regarding the possible effects of age, duration, dose and type of NSAID and whether effect modification by smoking status or sex exists
Relativistic theory of magnetic scattering of x rays: Application to ferromagnetic iron
We present a detailed description of a first-principles formalism for magnetic scattering of circularly polar- ized x rays from solids in the framework of the fully relativistic spin-polarized multiple-scattering theory. The scattering amplitudes are calculated using a standard time-dependent perturbation theory to second order in the electron-photon interaction vertex. Particular attention is paid to understanding the relative importance of the positive- and negative-energy solutions of the Dirac equation to the scattering amplitude. The advantage of the present theory as compared with other recent works on magnetic x-ray scattering is that, being fully relativistic, spin-orbit coupling and spin-polarization effects are treated on an equal footing. Second, the electron Green’s function expressed in terms of the path operators in the multiple-scattering theory allows us to include the contribution of the crystalline environment to the scattering amplitude. To illustrate the use of the method we have done calculations on the anomalous magnetic scattering at the K , L_II , and L_III absorption edges of ferromagnetic iron
Anthelmintic activity and cytotoxic effects of compounds isolated from the fruits of Ozoroa insignis del. (Anacardiaceae)
Ozoroa insignis Del. is an ethnobotanical plant widely used in traditional medicine for various ailments, including schistosomiasis, tapeworm, and hookworm infections. From the so far not investigated fruits of Ozoroa insignis, the anthelmintic principles could be isolated through bioassay-guided isolation using Caenorhabditis elegans and identified by NMR spectroscopic analysis and mass spectrometric studies. Isolated 6-[8(Z)-pentadecenyl] anacardic (1), 6-[10(Z)-heptadecenyl] anacardic acid (2), and 3-[7(Z)-pentadecenyl] phenol (3) were evaluated against the 5 parasitic organisms Schistosoma mansoni (adult and newly transformed schistosomula), Strongyloides ratti, Heligmosomoides polygyrus, Necator americanus, and Ancylostoma ceylanicum, which mainly infect humans and other mammals. Compounds 1-3 showed good activity against Schistosoma mansoni, with compound 1 showing the best activity against newly transformed schistosomula with 50% activity at 1microM. The isolated compounds were also evaluated for their cytotoxic properties against PC-3 (human prostate adenocarcinoma) and HT-29 (human colorectal adenocarcinoma) cell lines, whereby compounds 2 and 3 showed antiproliferative activity in both cancer cell lines, while compound 1 exhibited antiproliferative activity only on PC-3 cells. With an IC50 value of 43.2 microM, compound 3 was found to be the most active of the 3 investigated compounds
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