Simultaneous recording of evoked potentials and T2*-weighted MR images during somatosensory stimulation of rat

Somatosensory evoked potentials (SEP) and T2*-weighted nuclear magnetic resonance (NMR) images were recorded simultaneously during somatosensory stimulation of rat to investigate the relationship between electrical activation of the brain tissue and the signal intensity change in functional NMR imaging. Electrical forepaw stimulation was performed in Wistar rats anesthetized with -chloralose. SEPs were recorded with calomel electrodes at stimulation frequencies of 1.5, 3, 4.5, and 6 Hz. At the same time, T2*-weighted imaging was performed, and the signal intensity increase during stimulation was correlated with the mean amplitude of the SEP. Both the stimulation-evoked signal intensity increase in T2*-weighted images and the amplitude of SEPs were dependent on the stimulation frequency, with the largest signals at a stimulation frequency of 1.5 Hz and decreasing activations with increasing frequencies. The feasibility of simultaneous, artifact-free recordings of T2*-weighted NMR images and of evoked potentials is proved. Furthermore, the study demonstrates - in the intact brain - the validity of functional magnetic resonance imaging for estimating the intensity of electrocortical activation

Cross Talk Between Plasma Membrane Na+/Ca2+ Exchanger-1 and TRPC/Orai-Containing Channels: Key Players in Arterial Hypertension

Arterial smooth muscle (ASM) Na(+)/Ca(2+) exchanger type 1 (NCX1) and TRPC/Orai-containing receptor/store-operated cation channels (ROC/SOC) are clustered with α2 Na(+) pumps in plasma membrane microdomains adjacent to the underlying junctional sarcoplasmic reticulum. This arrangement enables these transport proteins to function as integrated units to help regulate local Na(+) metabolism, Ca(2+) signaling and arterial tone. They thus influence vascular resistance and blood pressure (BP). For instance, up-regulation of NCX1 and TRPC6 has been implicated in the pathogenesis of high BP in several models of essential hypertension: ouabain-induced hypertensive rats, Milan hypertensive strain rats, and Dahl salt-sensitive hypertensive rats, which all have elevated plasma ouabain levels. Enhanced expression and function of arterial smooth muscle NCX1 and TRPC/Orai1-containing channels in experimental and clinical hypertension implies that these proteins are potential targets for pharmacological intervention

Mortality after surgery in Europe: a 7 day cohort study

Background: Clinical outcomes after major surgery are poorly described at the national level. Evidence of heterogeneity between hospitals and health-care systems suggests potential to improve care for patients but this potential remains unconfirmed. The European Surgical Outcomes Study was an international study designed to assess outcomes after non-cardiac surgery in Europe.Methods: We did this 7 day cohort study between April 4 and April 11, 2011. We collected data describing consecutive patients aged 16 years and older undergoing inpatient non-cardiac surgery in 498 hospitals across 28 European nations. Patients were followed up for a maximum of 60 days. The primary endpoint was in-hospital mortality. Secondary outcome measures were duration of hospital stay and admission to critical care. We used χ² and Fisher’s exact tests to compare categorical variables and the t test or the Mann-Whitney U test to compare continuous variables. Significance was set at p<0·05. We constructed multilevel logistic regression models to adjust for the differences in mortality rates between countries.Findings: We included 46 539 patients, of whom 1855 (4%) died before hospital discharge. 3599 (8%) patients were admitted to critical care after surgery with a median length of stay of 1·2 days (IQR 0·9–3·6). 1358 (73%) patients who died were not admitted to critical care at any stage after surgery. Crude mortality rates varied widely between countries (from 1·2% [95% CI 0·0–3·0] for Iceland to 21·5% [16·9–26·2] for Latvia). After adjustment for confounding variables, important differences remained between countries when compared with the UK, the country with the largest dataset (OR range from 0·44 [95% CI 0·19 1·05; p=0·06] for Finland to 6·92 [2·37–20·27; p=0·0004] for Poland).Interpretation: The mortality rate for patients undergoing inpatient non-cardiac surgery was higher than anticipated. Variations in mortality between countries suggest the need for national and international strategies to improve care for this group of patients.Funding: European Society of Intensive Care Medicine, European Society of Anaesthesiology