biosynthesize high-quality magnetite nanoparticles, called magnetosomes, and arrange them into a chain that behaves like a magnetic compass. Here we perform magnetometry and polarized small-angle neutron scattering (SANS) experiments on a powder of freeze-dried and immobilized . We confirm that the individual magnetosomes are single-domain nanoparticles and that an alignment of the particle moments along the magnetic field direction occurs exclusively by an internal, coherent rotation. Our magnetometry results of the bacteria powder indicate an absence of dipolar interactions between the particle chains and a dominant uniaxial magnetic anisotropy. Finally, we can verify by SANS that the chain structure within the immobilized, freeze-dried bacteria is preserved also after application of large magnetic fields up to 1 T.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9419280 | PMC |
http://dx.doi.org/10.1039/c9na00434c | DOI Listing |
Hum Brain Mapp
January 2025
Institute of Cognitive Neurology and Dementia Research, Otto-von-Guericke University, Magdeburg, Germany.
The present study investigated the neuromodulatory substrates of salience processing and its impact on memory encoding and behaviour, with a specific focus on two distinct types of salience: reward and contextual unexpectedness. 46 Participants performed a novel task paradigm modulating these two aspects independently and allowing for investigating their distinct and interactive effects on memory encoding while undergoing high-resolution fMRI. By using advanced image processing techniques tailored to examine midbrain and brainstem nuclei with high precision, our study additionally aimed to elucidate differential activation patterns in subcortical nuclei in response to reward-associated and contextually unexpected stimuli, including distinct pathways involving in particular dopaminergic modulation.
View Article and Find Full Text PDFGenet Epidemiol
January 2025
Clinical and Translational Epidemiology Unit, Massachusetts General Hospital, Boston, Massachusetts, USA.
Large-scale gene-environment interaction (GxE) discovery efforts often involve analytical compromises for the sake of data harmonization and statistical power. Refinement of exposures, covariates, outcomes, and population subsets may be helpful to establish often-elusive replication and evaluate potential clinical utility. Here, we used additional datasets, an expanded set of statistical models, and interrogation of lipoprotein metabolism via nuclear magnetic resonance (NMR)-based lipoprotein subfractions to refine a previously discovered GxE modifying the relationship between physical activity (PA) and HDL-cholesterol (HDL-C).
View Article and Find Full Text PDFPharm Dev Technol
January 2025
Department of Pharmacy, School of Chemistry and Chemical Engineering, Liaoning Normal University, Dalian 116029, China.
In this paper, the pH-sensitive targeting functional material NGR-poly(2-ethyl-2-oxazoline)-cholesteryl methyl carbonate (NGR-PEtOz-CHMC, NPC) modified quercetin (QUE) liposomes (NPC-QUE-L) was constructed. The structure of NPC was confirmed by infrared spectroscopy (IR) and nuclear magnetic resonance hydrogen spectrum (H-NMR). Pharmacokinetic results showed that the accumulation of QUE in plasma of the NPC-QUE-L group was 1.
View Article and Find Full Text PDFNMR Biomed
February 2025
Department of Biomedical Engineering, Yale University, New Haven, Connecticut, USA.
Cellular metabolism is inextricably linked to transmembrane levels of proton (H), sodium (Na), and potassium (K) ions. Although reduced sodium-potassium pump (Na-K ATPase) activity in tumors directly disturbs transmembrane Na and K levels, this dysfunction is a result of upregulated aerobic glycolysis generating excessive cytosolic H (and lactate) which are extruded to acidify the interstitial space. These oncogene-directed metabolic changes, affecting intracellular Na and H, can be further exacerbated by upregulation of ion exchangers/transporters.
View Article and Find Full Text PDFACS Appl Bio Mater
January 2025
Advanced Magnetic Materials Research Center, School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran, North Kargar Street, Tehran 11155-4563, Iran.
Although 3D printing is becoming a dominant technique for scaffold preparation in bone tissue engineering (TE), developing hydrogel-based ink compositions with bioactive and self-healing properties remains a challenge. This research focuses on developing a bone scaffold based on a composite hydrogel, which maintains its self-healing properties after incorporating bioactive glass and is 3D-printable. The plain hydrogel ink was synthesized using natural polymers of 1 wt % N-carboxyethyl chitosan, 2 wt % hyaluronic acid aldehyde, 0.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!