Disruption of the mitochondrial network in a mouse model of Huntington's disease visualized by in-tissue multiscale 3D electron microscopy.

Huntington's disease (HD) is an inherited neurodegenerative disorder caused by an expanded CAG repeat in the coding sequence of huntingtin protein. Initially, it predominantly affects medium-sized spiny neurons (MSSNs) of the corpus striatum. No effective treatment is still available, thus urging the identification of potential therapeutic targets.

Genotoxicity and heating Performance of VFeO nanoparticles in Health applications.

The applications of magnetic nanoparticles (MNPs) as biocatalysts in different biomedical areas have been evolved very recently. One of the main challenges in this field is to design affective MNPs surfaces with catalytically active atomic centres, while producing minimal toxicological side effects on the hosting cell or tissues. MNPs of vanadium spinel ferrite (VFeO) are a promising material for mimicking the action of natural enzymes in degrading harmful substrates due to the presence of active V centres.

Enhanced Cellular Transduction of Nanoparticles Resistant to Rapidly Forming Plasma Protein Coronas.

Nanoparticles (NPs) are increasingly being developed as biomedical platforms for drug/nucleic acid delivery and imaging. However, in biological fluids, NPs interact with a wide range of proteins that form a coating known as protein corona. Coronae can critically influence self-interaction and binding of other molecules, which can affect toxicity, promote cell activation, and inhibit general or specific cellular uptake.

PolishEM: image enhancement in FIB-SEM.

Summary: We have developed a software tool to improve the image quality in focused ion beam-scanning electron microscopy (FIB-SEM) stacks: PolishEM. Based on a Gaussian blur model, it automatically estimates and compensates for the blur affecting each individual image. It also includes correction for artifacts commonly arising in FIB-SEM (e.

Ultra-fast direct growth of metallic micro- and nano-structures by focused ion beam irradiation.

An ultra-fast method to directly grow metallic micro- and nano-structures is introduced. It relies on a Focused Ion Beam (FIB) and a condensed layer of suitable precursor material formed on the substrate under cryogenic conditions. The technique implies cooling the substrate below the condensation temperature of the gaseous precursor material, subsequently irradiating with ions according to the wanted pattern, and posteriorly heating the substrate above the condensation temperature.

Effects of biological buffer solutions on the peroxidase-like catalytic activity of FeO nanoparticles.

Iron oxide nanoparticles (IONPs) are frequently used in biomedical applications due to their magnetic properties and putative chemical stability. Nevertheless, their well-known ability to mimic some features of the peroxidase enzyme activity under specific conditions of pH and temperature could lead to the formation of potentially harmful free radical species. In addition to the intrinsic enzyme-like activity of IONPs, the buffer solution is an important external factor that can alter dramatically the IONP activity because the buffer species can interact with the surface of the particles.

The relevance of Brownian relaxation as power absorption mechanism in Magnetic Hyperthermia.

The Linear Response Theory (LRT) is a widely accepted framework to analyze the power absorption of magnetic nanoparticles for magnetic fluid hyperthermia. Its validity is restricted to low applied fields and/or to highly anisotropic magnetic nanoparticles. Here, we present a systematic experimental analysis and numerical calculations of the specific power absorption for highly anisotropic cobalt ferrite (CoFeO) magnetic nanoparticles with different average sizes and in different viscous media.

Controlling the dominant magnetic relaxation mechanisms for magnetic hyperthermia in bimagnetic core-shell nanoparticles.

We report a simple and effective way to control the heat generation of a magnetic colloid under alternate magnetic fields by changing the shell composition of bimagnetic core-shell Fe3O4/ZnxCo1-xFe2O4 nanoparticles. The core-shell structure constitutes a magnetically-coupled biphase system, with an effective anisotropy that can be tuned by the substitution of Co2+ by Zn2+ ions in the shell. Magnetic hyperthermia experiments of nanoparticles dispersed in hexane and butter oil showed that the magnetic relaxation is dominated by Brown relaxation mechanism in samples with higher anisotropy (i.

Cell damage produced by magnetic fluid hyperthermia on microglial BV2 cells.

We present evidence on the effects of exogenous heating by water bath (WB) and magnetic hyperthermia (MHT) on a glial micro-tumor phantom. To this, magnetic nanoparticles (MNPs) of 30-40 nm were designed to obtain particle sizes for maximum heating efficiency. The specific power absorption (SPA) values (f = 560 kHz, H = 23.

Magnetic hyperthermia enhances cell toxicity with respect to exogenous heating.

Magnetic hyperthermia is a new type of cancer treatment designed for overcoming resistance to chemotherapy during the treatment of solid, inaccessible human tumors. The main challenge of this technology is increasing the local tumoral temperature with minimal side effects on the surrounding healthy tissue. This work consists of an in vitro study that compared the effect of hyperthermia in response to the application of exogenous heating (EHT) sources with the corresponding effect produced by magnetic hyperthermia (MHT) at the same target temperatures.

The orientation of the neuronal growth process can be directed via magnetic nanoparticles under an applied magnetic field.

There is a growing body of evidence indicating the importance of physical stimuli for neuronal growth and development. Specifically, results from published experimental studies indicate that forces, when carefully controlled, can modulate neuronal regeneration. Here, we validate a non-invasive approach for physical guidance of nerve regeneration based on the synergic use of magnetic nanoparticles (MNPs) and magnetic fields (Ms).

Neuronal cells loaded with PEI-coated FeO nanoparticles for magnetically guided nerve regeneration.

We report a one-step synthesis protocol for obtaining polymer-coated magnetic nanoparticles (MNPs) engineered for uploading neural cells. Polyethyleneimine-coated FeO nanoparticles (PEI-MNPs) with sizes of 25 ± 5 nm were prepared by oxidation of Fe(OH) by nitrate in basic aqueous media and adding PEI in situ during synthesis. The obtained PEI-MNP cores displayed a neat octahedral morphology and high crystallinity.

Poly-l-lysine-coated magnetic nanoparticles as intracellular actuators for neural guidance.

Purpose: It has been proposed in the literature that Fe(3)O(4) magnetic nanoparticles (MNPs) could be exploited to enhance or accelerate nerve regeneration and to provide guidance for regenerating axons. MNPs could create mechanical tension that stimulates the growth and elongation of axons. Particles suitable for this purpose should possess (1) high saturation magnetization, (2) a negligible cytotoxic profile, and (3) a high capacity to magnetize mammalian cells.