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971.
Celina Rahn Tamara Bakuradze Simone Stegmüller Jens Galan Sonja Niesen Peter Winterhalter Elke Richling 《International journal of molecular sciences》2023,24(1)
Polyphenols are a diverse and widely distributed class of secondary metabolites, which possess numerous beneficial properties including a modulation of glucose and lipid metabolism. This placebo-controlled human intervention study was performed to explore effects of polyphenol-rich beverage (PRB) uptake on lipid metabolism, as well as DNA integrity. In this case, 36 healthy men were randomly divided to consume either 750 mL of a PRB (containing 51% chokeberry, cranberry, and pomegranate) or a placebo drink daily for eight weeks. Only PRB consumption was found to decrease fat and protein intakes significantly compared to the preceding one-week washout period. During the intervention with PRB an increased fat-free mass was shown after four weeks, whereas a significant elevation in body weight and leptin was observed in placebo group. Blood lipids were not significantly altered after PRB consumption, while triglyceride levels increased after placebo drink intake. In platelets, a significant inhibition of phosphodiesterase (PDE) activity was observed, more pronounced in test group. Consuming the PRB decreased total DNA strand breaks in whole blood as well as H2O2-induced breaks in isolated lymphocytes. Overall, our study suggested beneficial effects on lipid metabolism by reduced energy intake, modulation of biomarkers such as PDE activity and improved DNA integrity associated with PRB consumption. 相似文献
972.
Is There Reduced Hemodynamic Brain Activation in Multiple Sclerosis Even with Undisturbed Cognition?
Bianca Wagner Clara L. Hrig Bertram Walter Jens Sommer Gebhard Sammer Martin Berghoff 《International journal of molecular sciences》2023,24(1)
Cognitive impairments related to changes in deep gray matter and other brain regions occur in up to 70% of people with multiple sclerosis. But do such brain changes also occur in patients without significant cognitive impairment? Eighteen participants with relapsing-remitting multiple sclerosis (RRMS) and fifteen healthy controls participated in this study. Cognitive status, depression, and fatigue were assessed using the Multiple Sclerosis Inventory of Cognition (MUSIC), Beck’s Depression Inventory (BDI-II), and the Fatigue Severity Scale (FSS). fMRI was recorded while a participant performed the modified attention network test (ANT). The effects of ANT executive attention network on hemodynamic activation of a priori defined regions of interest, including the hippocampus, anterior cingulate cortex (ACC), thalamus, caudate nucleus, pallidum, and putamen were studied. The individual lesion load was estimated. For fMRI data analysis a general linear model with randomization statistics including threshold-free cluster enhancement as implemented in the FSL software was used. Participants with RRMS showed reduced activation of the executive attention network in the hippocampus, pallidum, and ACC. The thalamus was involved in both group activations but did not differ between groups. In summary, functional changes in the brain can also be demonstrated in RRMS patients without cognitive deficits. The affected brain regions can best be assigned to the attention network for executive control. This association could likely serve as a biological indicator of susceptibility to imminent cognitive impairment in MS. 相似文献
973.
Nicola Brandt Jan Philipp Willmer Maurilyn S. Ayon-Olivas Veronika Banicka Martin Witt Andreas Wree Isabel Groß Anne Glser Jens Hausmann Anja U. Bruer 《International journal of molecular sciences》2022,23(21)
The functional importance of neuronal differentiation of the transmembrane proteins’ plasticity-related genes 3 (PRG3) and 5 (PRG5) has been shown. Although their sequence is closely related, they promote different morphological changes in neurons. PRG3 was shown to promote neuritogenesis in primary neurons; PRG5 contributes to spine induction in immature neurons and the regulation of spine density and morphology in mature neurons. Both exhibit intracellularly located C-termini of less than 50 amino acids. Varying C-termini suggested that these domains shape neuronal morphology differently. We generated mutant EGFP-fusion proteins in which the C-termini were either swapped between PRG3 and PRG5, deleted, or fused to another family member, plasticity-related gene 4 (PRG4), that was recently shown to be expressed in different brain regions. We subsequently analyzed the influence of overexpression in immature neurons. Our results point to a critical role of the PRG3 and PRG5 C-termini in shaping early neuronal morphology. However, the results suggest that the C-terminus alone might not be sufficient for promoting the morphological effects induced by PRG3 and PRG5. 相似文献
974.
Munir A. Al-Zeer Franziska Prehn Stefan Fiedler Ulrich Lienert Michael Krisch Johanna Berg Jens Kurreck Guido Hildebrandt Elisabeth Schültke 《International journal of molecular sciences》2022,23(17)
Radiotherapy is an important component in the treatment of lung cancer, one of the most common cancers worldwide, frequently resulting in death within only a few years of diagnosis. In order to evaluate new therapeutic approaches and compare their efficiency with regard to tumour control at a pre-clinical stage, it is important to develop standardized samples which can serve as inter-institutional outcome controls, independent of differences in local technical parameters or specific techniques. Recent developments in 3D bioprinting techniques could provide a sophisticated solution to this challenge. We have conducted a pilot project to evaluate the suitability of standardized samples generated from 3D printed human lung cancer cells in radiotherapy studies. The samples were irradiated at high dose rates using both broad beam and microbeam techniques. We found the 3D printed constructs to be sufficiently mechanically stable for use in microbeam studies with peak doses up to 400 Gy to test for cytotoxicity, DNA damage, and cancer cell death in vitro. The results of this study show how 3D structures generated from human lung cancer cells in an additive printing process can be used to study the effects of radiotherapy in a standardized manner. 相似文献
975.
Michael Tanja; Blechert Jens; Vriends Noortje; Margraf Jürgen; Wilhelm Frank H. 《Canadian Metallurgical Quarterly》2007,116(3):612
Enhanced conditionability has been proposed as a crucial factor in the etiology and maintenance of panic disorder (PD). To test this assumption, the authors of the current study examined the acquisition and extinction of conditioned responses to aversive stimuli in PD. Thirty-nine PD patients and 33 healthy control participants took part in a differential aversive conditioning experiment. A highly annoying but not painful electrical stimulus served as the unconditioned stimulus (US), and two neutral pictures were used as either the paired conditioned stimulus (CS+) or the unpaired conditioned stimulus (CS-). Results indicate that PD patients do not show larger conditioned responses during acquisition than control participants. However, in contrast to control participants, PD patients exhibited larger skin conductance responses to CS+ stimuli during extinction and maintained a more negative evaluation of them, as indicated by valence ratings obtained several times throughout the experiment. This suggests that PD patients show enhanced conditionability with respect to extinction. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
976.
Jens Westedt Frank Loescher Stefan Seeger 《Journal of The Association for Laboratory Automation》2000,5(3):69
One of the most important issues in bioanalytical science is the reproducible ultra-sensitive detection of biomolecules. At present an increasing demand for routine applications is observed for a lot of tasks in pharmaceutical high throughput screening, medical diagnostics and food and environmental analysis. We developed a detection system based on confocal laser-induced fluorescence spectroscopy. The components consist of an apparatus - the so called LB8®-Counter - and specially coated glass bottom microplates, the LB8®-Plates. Together they generate molecular recognition events of biomolecules even down to the single molecule level. 相似文献
977.
Jens Twiefel Björn Richter Thomas Sattel Jörg Wallaschek 《Journal of Electroceramics》2008,20(3-4):203-208
Many modern devices especially for ubiquitous computing or wireless sensor networks need a long life energy source. Batteries
or accumulators are often an insufficient solution. Low frequency vibrations can be found in the most technical facilities
or even in the human movements. Even while these vibrations are neither wanted nor used in the most times, they enable us
to generate electrical energy. Piezoelectric flexural transducers are a promising choice for utilizing the vibrations for
energy harvesting. There are two major influences on the amount of generated energy. First there is the frequency behavior
of the piezoelectric transducers, for optimal power output the transducer should be driven in resonance. Second, the energy
output is highly dependent on the electrical load of the connected application. Both circumstances, working frequency and
electrical load, typically are boundary conditions for the development of the generator. Therefore, it is necessary to handpick
the type of piezoelectric elements. To meet the requirements of development engineers, a model based design method for energy
harvesting systems is needed. As a first step towards such a method, this work proposes a model for the estimations of the
power output of piezoelectric flexural transducers. For the validation of this model an experiment is described in detail.
The results of the model and the experiments are compared. 相似文献
978.
This study examined whether automatic stereotypes captured by the implicit association test (IAT) can predict real hiring discrimination against the obese. In an unobtrusive field experiment, job applications were sent to a large number of real job vacancies. The applications were matched on credentials but differed with respect to the applicant's weight. Discriminatory behavior was quantified by the extent to which the hiring managers invited normal-weight versus obese applicants to a job interview. Several months after the behavioral data were obtained, the hiring managers completed an obesity IAT and explicit hiring preference measures. Only the IAT scores reliably predicted interview decisions. More specifically, hiring managers holding more negative automatic stereotypes about the obese were less likely to invite an obese applicant for an interview. The present research is the first to show that automatic bias predicts labor market discrimination against obese individuals. Practical implications are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
979.
980.
Jean-Marc Linares Julien Chaves-Jacob Heinrich Schwenke Andrew Longstaff Simon Fletcher Jakob Flore Eckart Uhlmann Jens Wintering 《Precision Engineering》2014
This paper deals with the accuracy of compensation of machine tools using a tracking interferometer using the multilateration method. The measurement strategy and thermal drift compensation of the measurements are studied. It shows that most effects of temperature are accurately compensated by the laser tracking interferometer software. However, thermal drifts of accessories are not taken into account, and are therefore not corrected. To validate the robustness of procedures, the geometrical errors of the same machine tool were measured by five measurement strategies using the same equipment. Each strategy is devised and carried out independently by a different person from several institutions. For each strategy, the geometrical compensations were applied to a set of nominal tool path points. The difference, between the nominal points and the compensated or uncompensated points was calculated. This criterion was used to discuss the procedures employed by the participants. 相似文献