The properties of some complexes and salts containing the malonate or the C-substituted malonate group

Methods have been devised for the preparation of some malonate and C-substituted malonate salts and complexes with various metal ions. The solid state ultraviolet, visible and infrared spectra have been measured and discussed with respect to the bonding of the compounds. Infrared spectra studies confirmed that all complexes involve bonding through the carboxyl oxygen. Infrared analysis of these complexes confirmed the presence of two bands between 1600--1500 cm-1 and 1400--1350 cm -1. This differs from the position of such bands in the free acids, which upon coordination causes these bands to be shifted to lower or higher frequencies. The formation of these complexes through the carboxyl oxygen atoms has been confirmed from the X-ray analysis. The visible electronic spectra of the transition metal complexes indicated the most probable stereochemical shapes of the metal ion. The magnetic properties of Cu(II), Ni(II), Co (II), Fe(III), Mn(III) and Cr(III) complexes of malonate, ethyl and benzylmalonate were studied over a wide range of temperatures. The magnetic susceptibilities of all the compounds were found to be normal. Hence the Curie-Weiss Law was obeyed. The Mossbauer spectra of iron(III)malonate, ethyl and benzylmalonate complexes exhibited a similar pattern characteristic of a high-spin octahedral structure. X-ray crystallographic data of Zn(II), Cd(II), Ca(II), Ba(II), Co(III) and Al(III)malonate and Zn(II) ethylmalonate complexes are reported. However, X-ray powder photographs of Zn(II) malonate confirmed it asisomorphous with Co(II) and Ni(II)malonate. The crystal structure of Al(III) malonato complexes were studied by the single-crystal method and the cell parameters were obtained. Finally, 1H n.m.r. and 13C n.m.r. of some malonic acids and the chelated malonate group and the exchange of [alpha]-protons with deuterium from the solvent D2O are reported.<p

Myocardial infarction with unusual presentation of otalgia: a case report

A rare case of a patient with unusual symptoms of earache and sore throat for cardiac ischemia is presented. A diagnosis of non-ST-segment elevation myocardial infarction (NSTEMI) was made based on initial elevation of troponin and an abnormal electrocardiograph (ECG). Percutaneous coronary intervention (PCI) performed with stent placement in the occluded coronary vessel was followed by a decrease in troponin level and complete resolution of the ear and throat pain and patient recovery from cardiac ischemia

Non-invasive Vagus Nerve Stimulation in Healthy Humans Reduces Sympathetic Nerve Activity

Background: Vagus nerve stimulation (VNS) is currently used to treat refractory epilepsy and is being investigated as a potential therapy for a range of conditions, including heart failure, tinnitus, obesity and Alzheimer's disease. However, the invasive nature and expense limits the use of VNS in patient populations and hinders the exploration of the mechanisms involved. Objective: We investigated a non-invasive method of VNS through electrical stimulation of the auricular branch of the vagus nerve distributed to the skin of the ear – transcutaneous VNS (tVNS) and measured the autonomic effects. Methods: The effects of tVNS parameters on autonomic function in 48 healthy participants were investigated using heart rate variability (HRV) and microneurography. tVNS was performed using a transcutaneous electrical nerve stimulation (TENS) machine and modified surface electrodes. Participants visited the laboratory once and received either active (200 μs, 30 Hz; n = 34) or sham (n = 14) stimulation. Results: Active tVNS significantly increased HRV in healthy participants (P = 0.026) indicating a shift in cardiac autonomic function toward parasympathetic predominance. Microneurographic recordings revealed a significant decrease in frequency (P = 0.0001) and incidence (P = 0.0002) of muscle sympathetic nerve activity during tVNS. Conclusion: tVNS can increase HRV and reduce sympathetic nerve outflow, which is desirable in conditions characterized by enhanced sympathetic nerve activity, such as heart failure. tVNS can therefore influence human physiology and provide a simple and inexpensive alternative to invasive VNS