Crossed-coil NMR probes are a useful tool for reducing sample heating for biological solid state NMR. In a crossed-coil probe, the higher frequency 1H field, which is the primary source of sample heating in conventional probes, is produced by a separate low-inductance resonator. Because a smaller driving voltage is required, the electric field across the sample and the resultant heating is reduced. In this work we describe the development of a magic angle spinning (MAS) solid state NMR probe utilizing a dual resonator. This dual resonator approach, referred to as “Low-E,” was originally developed to reduce heating in samples of mechanically aligned membranes. The study of inherently dilute systems, such as proteins in lipid bilayers, via MAS techniques requires large sample volumes at high field to obtain spectra with adequate signal-to-noise ratio under physiologically relevant conditions. With the Low-E approach, we are able to obtain homogeneous and sufficiently strong radiofrequency fields for both 1H and 13C frequencies in a 4 mm probe with a 1H frequency of 750 MHz. The performance of the probe using windowless dipolar recoupling sequences is demonstrated on model compounds as well as membrane embedded peptides.

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For the first time, 15 N solid-state NMR experiments were conducted on wild-type phospholamban (WT-PLB) embedded inside mechanically oriented phospholipid bilayers to investigate the topology of its cytoplasmic and transmembrane domains.15 N solid-state NMR spectra of site-specific 15 N-labeled WT-PLB indicate that the transmembrane domain has a tilt angle of 13°6 6°with respect to the POPC (1-palmitoyl-2-oleoyl-sn-glycero-phosphocholine) bilayer normal and that the cytoplasmic domain of WT-PLB lies on the surface of the phospholipid bilayers. Comparable results were obtained from sitespecific 15 N-labeled WT-PLB embedded inside DOPC/DOPE (1,2-dioleoyl-sn-glycero-3-phosphocholine/ 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine) mechanically oriented phospholipids' bilayers. The new NMR data support a pinwheel geometry of WT-PLB, but disagree with a bellflower structure in micelles, and indicate that the orientation of the cytoplasmic domain of the WT-PLB is similar to that reported for the monomeric AFA-PLB mutant.

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Objectives:Statins by their anti-inflammatory and endothelial stabilizing effect can be beneficial in patients with chronic obstructive pulmonary disease (COPD) and pulmonary hypertension (PH). The present study was done to evaluate the effect of rosuvastatin on pulmonary functions and quality of life (QOL) in patients with concomitant COPD and PH.Materials and Methods:It was a prospective, randomized, double-blind, placebo-controlled, study conducted in patients with COPD and PH. A total of sixty patients were assigned to receive either rosuvastatin 10 mg or placebo once a day in addition to their conventional treatment for 12 weeks. Routine blood investigations, pulmonary functions, echocardiogram, exercise capacity, and QOL using a questionnaire were assessed at the baseline and after 12 weeks.Results:In patients of rosuvastatin group, there was a statistically significant increase in peak expiratory flow rate (PEFR) (P = 0.04) but no significant change in other pulmonary functions: Forced vital capacity (FVC), forced expiratory volume at 1 s (FVC, FEV1, FEV1/FVC), and echocardiogram parameters. There was a significant increase in 6-min walk test (6-min walk distance) (P = 0.03) at the end of 12 weeks. On comparing with placebo, rosuvastatin showed a significant reduction (P = 0.045) in COPD exacerbations while adverse effects did not differ.Conclusion:Statins have a favorable effect on patients with COPD and PH regarding the improvement in PEFR, COPD exacerbations, and exercise capacity. Such effects can be beneficial in these patients and more so in patients with concomitant coronary artery disease or hyperlipidemia where long-term benefits of statins have been established.

Abstract2D NMR relies on monitoring systematic changes in the phases incurred by spin coherences as a function of an encoding time t 1 , whose value changes over the course of independent experiments. The intrinsic multiscan nature of such protocols implies that resistive and/or hybrid magnets, capable of delivering the highest magnetic field strengths but possessing poor temporal stabilities, become unsuitable for 2D NMR acquisitions. It is here shown with a series of homo-and hetero-nuclear examples that such limitations can be bypassed using recently proposed 2D "ultrafast" acquisition schemes, which correlate interactions along all spectral dimensions within a single scan.

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