An Improved Method for Magnetic Nanocarrier Drug Delivery across the Cell Membrane.

One of the crucial issues in the pharmacological field is developing new drug delivery systems. The main concern is to develop new methods for improving the drug delivery efficiencies such as low disruptions, precise control of the target of delivery and drug sustainability. Nowadays, there are many various methods for drug delivery systems. Carbon-based nanocarriers are a new efficient tool for translocating drug into the defined area or cells inside the body. These nanocarriers can be functionalized with proteins, peptides and used to transport their freight to cells or defined areas. Since functionalized carbon-based nanocarriers show low toxicity and high biocompatibility, they are used in many nanobiotechnology fields. In this study, different shapes of nanocarrier are investigated, and the suitable magnetic field, which is applied using MRI for the delivery of the nanocarrier, is proposed. In this research, based on the force required to cross the membrane and MD simulations, the optimal magnetic field profile is designed. This optimal magnetic force field is derived from the mathematical model of the system and magnetic particle dynamics inside the nanocarrier. The results of this paper illustrate the effects of the nanocarrier's shapes on the percentage of success in crossing the membrane and the optimal required magnetic field.

Toward Epileptic Brain Region Detection Based on Magnetic Nanoparticle Patterning.

Resection of the epilepsy foci is the best treatment for more than 15% of epileptic patients or 50% of patients who are refractory to all forms of medical treatment. Accurate mapping of the locations of epileptic neuronal networks can result in the complete resection of epileptic foci. Even though currently electroencephalography is the best technique for mapping the epileptic focus, it cannot define the boundary of epilepsy that accurately. Herein we put forward a new accurate brain mapping technique using superparamagnetic nanoparticles (SPMNs). The main hypothesis in this new approach is the creation of super-paramagnetic aggregates in the epileptic foci due to high electrical and magnetic activities. These aggregates may improve tissue contrast of magnetic resonance imaging (MRI) that results in improving the resection of epileptic foci. In this paper, we present the mathematical models before discussing the simulation results. Furthermore, we mimic the aggregation of SPMNs in a weak magnetic field using a low-cost microfabricated device. Based on these results, the SPMNs may play a crucial role in diagnostic epilepsy and the subsequent treatment of this disease.

Impaired neurogenesis alters brain biomechanics in a neuroprogenitor-based genetic subtype of congenital hydrocephalus.

Hydrocephalus, characterized by cerebral ventricular dilatation, is routinely attributed to primary defects in cerebrospinal fluid (CSF) homeostasis. This fosters CSF shunting as the leading reason for brain surgery in children despite considerable disease heterogeneity. In this study, by integrating human brain transcriptomics with whole-exome sequencing of 483 patients with congenital hydrocephalus (CH), we found convergence of CH risk genes in embryonic neuroepithelial stem cells. Of all CH risk genes, TRIM71/lin-41 harbors the most de novo mutations and is most specifically expressed in neuroepithelial cells. Mice harboring neuroepithelial cell-specific Trim71 deletion or CH-specific Trim71 mutation exhibit prenatal hydrocephalus. CH mutations disrupt TRIM71 binding to its RNA targets, causing premature neuroepithelial cell differentiation and reduced neurogenesis. Cortical hypoplasia leads to a hypercompliant cortex and secondary ventricular enlargement without primary defects in CSF circulation. These data highlight the importance of precisely regulated neuroepithelial cell fate for normal brain-CSF biomechanics and support a clinically relevant neuroprogenitor-based paradigm of CH.

Optimal Magnetic Field for Crossing Super-Para-Magnetic Nanoparticles through the Brain Blood Barrier: A Computational Approach.

This paper scrutinizes the magnetic field effect to deliver the superparamagnetic nanoparticles (SPMNs) through the Blood Brain Barrier (BBB). Herein we study the interaction between the nanoparticle (NP) and BBB membrane using Molecular Dynamic (MD) techniques. The MD model is used to enhance our understanding of the dynamic behavior of SPMNs crossing the endothelial cells in the presence of a gradient magnetic field. Actuation of NPs under weak magnetic field offers the great advantage of a non-invasive drug delivery without the risk of causing injury to the brain. Furthermore, a weak magnetic portable stimulator can be developed using low complexity prototyping techniques. Based on MD simulation results in this paper, SPMNs can cross the cell membrane while experiencing very weak mechanical forces in the range of pN. This study also derives guidelines for the design of the SPMNs dedicated to crossing the BBB using external magnetic fields.

MRI-guided epilepsy detection.

One of the most common neurological brain disorder is epilepsy that happen as an abrupt seizure. Around 30% of patients with epilepsy resist to all forms of medical treatments and, therefore, the removal of epileptic brain tissue is the only solution to get these patients free from chronical seizures. Discovering the epileptic region is a first key into the treatment. In this paper, we introduced a method for epilepsy detection. In this method superparamagnetic nanoparticle, (SPMN) is used as a sensing material in order to investigate the epileptic area. Based on the magnetic field, first they are crossed through the Blood Brain Barrier (BBB). They can cross the blood-brain barrier into the brain by means of magnetic forces. In this study, the optimal force for crossing to the brain and nanoparticles aggregation by means of MRI magnetic field for crossing and weak magnetic field inside the brain have been considered. Nanoparticles aggregation can be used as a marker to increase the contrast of MRI images in the epileptic brain area.

Modeling and simulation of crossing magnetic nanoparticles through blood brain barrier (BBB).

Crossing the Blood Brain Barrier (BBB), despite its tight junctions, is of the great importance in a plethora of medical applications. As a result, this work is dedicated to molecular dynamics (MD) simulation of crossing through the BBB particularly under the effect of magnetic force. For this purpose, two cases of a coated gold nanocparticle with insulin and uncoated gold nanoparticle have been considered; there, the dominant governing parameters in each case are changed to identify the optimized condition for crossing nanoparticles. These parameters are of biological (ligand-receptor binding affinity), biophysical (membrane surface receptor density ratio and non-specific interaction parameter) or geometrical (size of components) origin. The most important part of this study is MD simulation of nanoparticles under the effect of magnetic field and the result shows that for crossing through BBB what force profile must be provided by the magnetic field.