On-Demand Chemomagnetic Modulation of Striatal Neurons Facilitated by Hybrid Magnetic Nanoparticles.

Minimally invasive manipulation of cell signaling is critical in basic neuroscience research and in developing therapies for neurological disorders. Here, we describe a wireless chemomagnetic neuromodulation platform for the on-demand control of primary striatal neurons that relies on nanoscale heating events. Iron oxide magnetic nanoparticles (MNPs) are functionally coated with thermoresponsive poly (oligo (ethylene glycol) methyl ether methacrylate) (POEGMA) brushes loaded with dopamine. Dopamine loaded MNPs-POEGMA are co-cultured with primary striatal neurons. When alternating magnetinec fields (AMF) are applied, MNPs undergo hysteresis power loss and dissipate heat. The local heat produced by MNPs initiates a thermodynamic phase transition on POEGMA brushes resulting in polymer collapse and dopamine release. AMF-triggered dopamine release enhances the response of dopamine ion channels expressed on the cell membranes enhancing the activity of ~50% of striatal neurons subjected to the treatment. Chemomagnetic actuation on dopamine receptors is confirmed by blocking D1 and D2 receptors. The reversible thermodynamic phase transition of POEGMA brushes allow the on-demand release of dopamine in multiple microdoses. AMF-triggered dopamine release from MNPs-POEGMA causes no cell cytotoxicity nor promotes cell ROS production. This research represents a fundamental step forward for the chemomagnetic control of neural activity using hybrid magnetic nanomaterials with tailored physical properties.

Divergent copper-catalyzed syntheses of 3-carboxylpyrroles and 3-cyanofurans from O-acetyl oximes and ß-ketoesters/nitriles.

The reaction between O-acetyl oximes and ß-ketoesters/nitriles catalyzed by copper generated polysubstituted pyrroles and furans, respectively, under redox-neutral reaction conditions. Using this protocol, pyrroles or furans could be obtained simply by choosing an appropriate active methylene compound. Although both transformations occur essentially under the same reaction conditions, control experiments indicated that they follow different mechanistic pathways.

Comparative Study on the Quality of Microcrystalline and Epitaxial Silicon Films Produced by PECVD Using Identical SiF4 Based Process Conditions.

Hydrogenated microcrystalline silicon (µc-Si:H) and epitaxial silicon (epi-Si) films have been produced from SiF4, H2 and Ar mixtures by plasma enhanced chemical vapor deposition (PECVD) at 200 °C. Here, both films were produced using identical deposition conditions, to determine if the conditions for producing µc-Si with the largest crystalline fraction (XC), will also result in epi-Si films that encompass the best quality and largest crystalline silicon (c-Si) fraction. Both characteristics are of importance for the development of thin film transistors (TFTs), thin film solar cells and novel 3D devices since epi-Si films can be grown or etched in a selective manner. Therefore, we have distinguished that the H2/SiF4 ratio affects the XC of µc-Si, the c-Si fraction in epi-Si films, and the structure of the epi-Si/c-Si interface. Raman and UV-Vis ellipsometry were used to evaluate the crystalline volume fraction (Xc) and composition of the deposited layers, while the structure of the films were inspected by high resolution transmission electron microscopy (HRTEM). Notably, the conditions for producing µc-Si with the largest XC are different in comparison to the fabrication conditions of epi-Si films with the best quality and largest c-Si fraction.

Complications of Renal Transplantation That Influence the Presence of Hyperuricemia in Its First Year of Evolution.

INTRODUCTION: Renal transplantation (RT) has evolved to improve its functionality. Some factors have been little studied, one of which is hyperuricemia and its impact on renal graft function. The objective of this study is to determine the prevalence of complications of renal transplantation and its influence on hyperuricemia values in the first year of evolution. MATERIAL AND METHODS: The authors completed a retrospective, observational study of 2 RT units in Mexico from January 2013 to December 2017. In total, 1009 files met the inclusion criteria; the levels of uric acid (UA) and creatinine (Cr) were determined before transplantation and in months 1, 3, 6, 9, and 12 after transplantation. Descriptive analysis was performed with measures of central tendency, measures of dispersion, difference of means with Student t test, and SPSS version 25 (IBM, Armonk, NY, United States). RESULTS: The mean pretransplant UA was 6.24 mg/dL (standard deviation [SD] 1.97); per month was 4.73 mg/dL (SD 1.49). There is a difference in means between categorized groups of UA in the 5 post-RT moments (1, 3, 6, 9, and 12 months). A positive correlation of 0.41 to 0.47 was found with Spearman's test. The delayed function of the graft influenced in the first month after transplant in presenting hyperuricemia and acute dysfunction in month 6 showed that the rejection had no significance at any time. CONCLUSIONS: The relationship between the values of UA and Cr in the RT represents a moderate positive correlation; delayed graft function in the first month impacts the presence of hyperuricemia, as well as acute dysfunction at month 6 after transplantation.