Publications by authors named "Nyberg N"

The fifth generation of radiofrequency communication, 5G, is currently being rolled out worldwide. Since September 2017, the EU 5G Appeal has been sent six times to the EU, requesting a moratorium on the rollout of 5G. This article reviews the 5G Appeal and the EU's subsequent replies, including the extensive cover letter sent to the EU in September 2021, requesting stricter guidelines for exposures to radiofrequency radiation (RFR).

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Much of our understanding of navigation comes from the study of individual species, often with specific tasks tailored to those species. Here, we provide a novel experimental and analytic framework integrating across humans, rats, and simulated reinforcement learning (RL) agents to interrogate the dynamics of behavior during spatial navigation. We developed a novel open-field navigation task ("Tartarus maze") requiring dynamic adaptation (shortcuts and detours) to frequently changing obstructions on the path to a hidden goal.

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The mammalian hippocampal formation contains several distinct populations of neurons involved in representing self-position and orientation. These neurons, which include place, grid, head direction, and boundary cells, are thought to collectively instantiate cognitive maps supporting flexible navigation. However, to flexibly navigate, it is necessary to also maintain internal representations of goal locations, such that goal-directed routes can be planned and executed.

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Flexible navigation relies on a cognitive map of space, thought to be implemented by hippocampal place cells: neurons that exhibit location-specific firing. In connected environments, optimal navigation requires keeping track of one's location and of the available connections between subspaces. We examined whether the dorsal CA1 place cells of rats encode environmental connectivity in four geometrically identical boxes arranged in a square.

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Background: Release of cardiac biomarkers is common after strenuous endurance exercise, but data on intermittent exercise are scarce. It has not been investigated whether cardiac troponin elevation is influenced depending on the type of exercise that an athlete is adapted to perform. We hypothesized that intermittent but not continuous exercise induces cardiac troponin elevation in professional athletes adapted to high-intensity intermittent exercise.

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Ethnopharmacological Relevance: Berries of Sorbus species have been used to treat type 2 diabetes in many regions in Europe.

Aims Of The Study: To investigate the inhibitory activity of berry extract of Sorbus on the digestive enzymes α-amylase and α-glucosidase, two important targets for management of blood glucose for type 2 diabetics. Furthermore, to test the anti-hyperglycaemic potential of S.

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The glutamate transporter GLT-1 is highly expressed in astrocytes but also in neurons, primarily in axon terminals. We generated a conditional neuronal GLT-1 KO using synapsin 1-Cre (synGLT-1 KO) to elucidate the metabolic functions of GLT-1 expressed in neurons, here focusing on the cerebral cortex. Both synaptosomal uptake studies and electron microscopic immunocytochemistry demonstrated knockdown of GLT-1 in the cerebral cortex in the synGLT-1 KO mice.

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Real-time measurements of the total loss of sweat, the rate of sweating, the temperature of sweat, and the concentrations of electrolytes and metabolites in sweat can provide important insights into human physiology. Conventional methods use manual collection processes (e.g.

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A comprehensive set of 3-phenylcoumarin analogues with polar substituents was synthesised for blocking oestradiol synthesis by 17-β-hydroxysteroid dehydrogenase 1 (HSD1) in the latter part of the sulphatase pathway. Five analogues produced ≥62% HSD1 inhibition at 5 µM and, furthermore, three of them produced ≥68% inhibition at 1 µM. A docking-based structure-activity relationship analysis was done to determine the molecular basis of the inhibition and the cross-reactivity of the analogues was tested against oestrogen receptor, aromatase, cytochrome P450 1A2, and monoamine oxidases.

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Monoamine oxidase B (MAO-B) catalyzes deamination of monoamines such as neurotransmitters dopamine and norepinephrine. Accordingly, small-molecule MAO-B inhibitors potentially alleviate the symptoms of dopamine-linked neuropathologies such as depression or Parkinson's disease. Coumarin with a functionalized 3-phenyl ring system is a promising scaffold for building potent MAO-B inhibitors.

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The present study was carried out to investigate the wound healing potentials of 17 medicinal plants historically used in Ghana for wound healing. Warm and cold water extracts were prepared from the 17 dried plant species and tested in vitro in the scratch assay with NIH 3T3 fibroblasts from mice. The wound healing scratch assay was used to evaluate the effect of the plants on cell proliferation and/or migration in vitro, as a test for potential wound healing properties.

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The Mediterranean plant (dicot, Apiaceae), also known as deadly carrot, produces the highly toxic compound thapsigargin. This compound is a potent inhibitor of the sarcoplasmic-endoplasmic reticulum Ca-ATPase calcium pump in mammals and is of industrial importance as the active moiety of the anticancer drug mipsagargin, currently in clinical trials. Knowledge of thapsigargin in planta storage and biosynthesis has been limited.

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Radix Astragali is a component of several traditional medicines used for the treatment of type 2 diabetes in China. Radix Astragali is known to contain isoflavones, which inhibit α-glucosidase in the small intestines, and thus lowers the blood glucose levels. In this study, 21 samples obtained from different regions of China were extracted with ethyl acetate, then the IC50-values were determined, and the crude extracts were analyzed by 1H-NMR spectroscopy.

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In drug discovery, lipophilicity is a key parameter for drug optimization. Lipophilicity determinations can be both work and time consuming, especially for non-UV active compounds. Herein, an improved and simple 1H NMR-based method is described to estimate the lipophilicity at physiological pH (logD) in 1-octanol and DO buffer.

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Drosophila, like most insects, are susceptible to low temperatures, and will succumb to temperatures above the freezing point of their hemolymph. For these insects, cold exposure causes a loss of extracellular ion and water homeostasis, leading to chill injury and eventually death. Chill-tolerant species are characterized by lower hemolymph [Na(+)] than chill-susceptible species and this lowered hemolymph [Na(+)] is suggested to improve ion and water homeostasis during cold exposure.

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Protein fibrillation is the pathological hallmark of several neurodegenerative diseases and also complicates the manufacturing and use of protein drugs. As a case study, the inhibitory activity of the natural compound aloin against insulin fibrillation was investigated. Based on Thioflavin T assays, high-performance liquid chromatography and transmission electron microscopy it was found that a degradation product of aloin, formed over weeks of storage, was able to significantly inhibit insulin fibrillation.

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Inhibition of the necrotizing hyaluronidase, phospholipase A2 and protease enzymes in four snake venoms by crude water and ethanol extracts of 88 plant species used against snakebites in traditional Chinese medicine was measured. High-resolution hyaluronidase inhibition profiles were constructed for the 22 plants showing highest hyaluronidase inhibition, and the results were used to guide subsequent structural analysis towards specific hyaluronidase inhibitors. Structural analysis was performed by high-performance liquid chromatography, high-resolution mass spectrometry, solid-phase extraction and nuclear magnetic resonance spectroscopy, i.

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Although cyclic peptide structures are usually investigated as highly constrained scaffolds, cyclic antimicrobial peptides of natural origin often feature flexible residues. Hereby we report our findings concerning a structure-activity study conducted on a model sequence by replacing a glycine residue with a variety of flexible residues (i.e.

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In this work, development of a new microplate-based high-resolution profiling assay using recombinant human aldose reductase is presented. Used together with high-resolution radical scavenging and high-resolution α-glucosidase assays, it provided the first report of a triple aldose reductase/α-glucosidase/radical scavenging high-resolution inhibition profile - allowing proof of concept with Radix Scutellariae crude extract as a polypharmacological herbal drug. The triple bioactivity high-resolution profiles were used to pinpoint bioactive compounds, and subsequent structure elucidation was performed with hyphenated high-performance liquid chromatography-high-resolution mass spectrometry-solid-phase extraction-nuclear magnetic resonance spectroscopy.

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The crude methanol extract of Pueraria lobata was investigated by dual high-resolution α-glucosidase inhibition and radical scavenging profiling combined with hyphenated HPLC-HRMS-SPE-NMR. Direct analysis of the crude extract without preceding purification was facilitated by combining chromatograms from two analytical-scale HPLC separations of 120 and 600 μg on-column, respectively. High-resolution α-glucosidase and radical scavenging profiles were obtained after microfractionation of the eluate in 96-well microplates.

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Concentrated solutions containing 6-aminocaproic acid and the excipients citric acid and sorbitol have been studied at temperatures of 50°C, 60°C, 70°C and 80°C as well as at 20°C. It has previously been reported that the commonly employed citric acid is a reactive excipient, and it is therefore important to thoroughly investigate a possible reaction between 6-aminocaproic acid and citric acid. The current study revealed the formation of 3-hydroxy-3,4-dicarboxy-butanamide-N-hexanoic acid between 6-aminocaproic acid and citric acid by high-resolution mass spectrometry (HRMS) and nuclear magnetic resonance spectroscopy (NMR).

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Bulbs and leaves of 35 Allium species and cultivars bought or collected in 2010-2012 were investigated with multivariate data analysis, high-resolution α-glucosidase inhibition assays and HPLC-HRMS-SPE-NMR with the aim of exploring the potential of Allium as a future functional food for management of type 2 diabetes. It was found that 30 out of 106 crude extracts showed more than 80% inhibition of the α-glucosidase enzyme at a concentration of 40mg/mL (dry sample) or 0.4g/mL (fresh sample).

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Extracts of five halophytes from southern Portugal (Arthrocnemum macrostachyum, Mesembryanthemum edule, Juncus acutus, Plantago coronopus and Halimione portulacoides), were studied for antioxidant, anti-inflammatory and in vitro antitumor properties. The most active extracts towards the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical were the methanol extracts of M. edule (IC₅₀ = 0.

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We present the antimicrobial and hemolytic activities of the decapeptide anoplin and 19 analogs thereof tested against methicillin-resistant Staphylococcus aureus ATCC 33591 (MRSA), Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853), vancomycin-resistant Enterococcus faecium (ATCC 700221) (VRE), and Candida albicans (ATCC 200955). The anoplin analogs contain substitutions in amino acid positions 2, 3, 5, 6, 8, 9, and 10. We use these peptides to study the effect of altering the charge and hydrophobicity of anoplin on activity against red blood cells and microorganisms.

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