New two in one magnetic fluorescent nanocomposites

Magnetite nanoparticles have been coated by a porphyrin derivative to produce new magnetic materials with fluorescent properties. The magnetic nanoparticles were prepared using two different methods, one based on sol-gel techniques and ultrasonic processing, and the other via a controlled chemical co-precipitation. Different types of porphyrin functionalised magnetic nanoparticles have been prepared and have been characterised by electron microscopy (TEM and SEM), XRD, FTIR, Raman, UV-vis, and fluorescence spectroscopy. Microscopy results showed the formation of core-shell nanostructures, with IR and photoluminescence spectroscopy results confirming the presence of porphyrin in the shell

A modular ditopic crown-shielded phosphate ion-pair receptor

The synthesis of a modular hybrid receptor containing both an aza macrocycle and crown ether is described; a complete thermodynamic characterisation of the binding properties, in water, of the zinc(II) complex of the receptor towards phosphate is presented and the parameters are compared to those of the aza macrocycle precursor

Synthesis and binding properties of hybrid cyclophane-azamacrocyclic receptors

Three new azamacrocyclic-cyclophane hybrid receptors L1, L2, and L3 have been synthesized that incorporate either 1,4,7,10-tetraazacyclododecane (cyclen) or 1,4,7-triazacyclononane (tacn) unit(s) tethered via a short amidic spacer to an electron donor and a H-bonding crown ether polycycle. The crown ether is designed to act as a host toward biologically relevant guests, whereas the macrocycle can coordinate a zinc(II) or a copper(II) ion. The pKa of this bound water in the zinc(II) complex of L1 and L2 is 7.5. Isothermal calorimetry experiments carried out on [ZnL1(OH2)](CF3SO3)2 and [Zn2L2(OH2)2](CF3SO3)4 in buffered water (pH 7.4) at 25 °C show that the host strongly binds a series of phosphate derivatives. In comparison, the complex [CuL3(OH2)2](CF3SO3)2 is a poor receptor toward phosphate substrates

A modular ditopic crown-shielded phosphate ion-pair receptor

The synthesis of a modular hybrid receptor containing both an aza macrocycle and crown ether is described; a complete thermodynamic characterisation of the binding properties, in water, of the zinc(II) complex of the receptor towards phosphate is presented and the parameters are compared to those of the aza macrocycle precursor

Cardiac arrhythmias in Dravet syndrome: an observational multicenter study

Objectives We ascertained the prevalence of ictal arrhythmias to explain the high rate of sudden unexpected death in epilepsy (SUDEP) in Dravet syndrome (DS).Methods We selected cases with clinical DS, >= 6 years, SCN1A mutation, and >= 1 seizure/week. Home-based ECG recordings were performed for 20 days continuously. Cases were matched for age and sex to two epilepsy controls with no DS and >= 1 major motor seizure during video-EEG. We determined the prevalence of peri-ictal asystole, bradycardia, QTc changes, and effects of convulsive seizures (CS) on heart rate, heart rate variability (HRV), and PR/QRS. Generalized estimating equations were used to account for multiple seizures within subjects, seizure type, and sleep/wakefulness.Results We included 59 cases. Ictal recordings were obtained in 45 cases and compared to 90 controls. We analyzed 547 seizures in DS (300 CS) and 169 in controls (120 CS). No asystole occurred. Postictal bradycardia was more common in controls (n = 11, 6.5%) than cases (n = 4, 0.7%; P = 0.002). Peri-ictal QTc-lengthening (>= 60ms) occurred more frequently in DS (n = 64, 12%) than controls (n = 8, 4.7%, P = 0.048); pathologically prolonged QTc was rare (once in each group). In DS, interictal HRV was lower compared to controls (RMSSD P = 0.029); peri-ictal values did not differ between the groups. Prolonged QRS/PR was rare and more common in controls (QRS: one vs. none; PR: three vs. one).Interpretation We did not identify major arrhythmias in DS which can directly explain high SUDEP rates. Peri-ictal QTc-lengthening was, however, more common in DS. This may reflect unstable repolarization and an increased propensity for arrhythmias