Determination of dipole coupling constants using heteronuclear multiple quantum NMR

The problem of extracting dipole couplings from a system of N spins I = 1/2 and one spin S by NMR techniques is analyzed. The resolution attainable using a variety of single quantum methods is reviewed. The theory of heteronuclear multiple quantum (HMQ) NMR is developed, with particular emphasis being placed on the superior resolution available in HMQ spectra. Several novel pulse sequences are introduced, including a two-step method for the excitation of HMQ coherence. Experiments on partially oriented [1−13C] benzene demonstrate the excitation of the necessary HMQ coherence and illustrate the calculation of relative line intensities. Spectra of high order HMQ coherence under several different effective Hamiltonians achievable by multiple pulse sequences are discussed. A new effective Hamiltonian, scalar heteronuclear recoupled interactions by multiple pulse (SHRIMP), achieved by the simultaneous irradiation of both spin species with the same multiple pulse sequence, is introduced. Experiments are described which allow heteronuclear couplings to be correlated with an S-spin spreading parameter in spectra free of inhomogeneous broadening

Single-center open-label randomized study of anemia management improvement in ESRD patients with secondary hyperparathyroidism

Whether anemia and mineral bone abnormalities (chronic kidney disease\u2013mineral bone disorder [CKD-MBD]) are associated still remains to be elucidated. Both anemia and CKD-MBD have been associated with adverse cardiovascular outcome and poor quality of life. However, recent evidence suggests that use of large doses of erythropoietin-stimulating agents (ESAs) to correct hemoglobin (Hb) may be detrimental in CKD. The Optimal Anemia Treatment in End Stage Renal Disease (ESRD) (Optimal ESRD Treatment) study will assess whether lowering of parathyroid hormone (PTH) is associated with a reduction in ESA consumption. The Optimal ESRD Treatment study is a pilot single-center open-label study with blinded end point (a prospective randomized open blinded end-point [PROBE] design) enrolling 50 patients on maintenance dialysis. Eligible patients with intact PTH (iPTH) 300-540 pg/mL and Hb 10-11.5 g/dL will be randomized 1:1 to strict PTH control (150-300 pg/mL) versus standard care (PTH range 300-540 pg/mL). Available drugs for CKD-MBD and anemia treatment will be managed by the attending physician to maintain the desired levels of PTH (according to study arm allocation) and Hb (10-11.5 g/dL). Echocardiographic data for cardiac structure and function as well as arterial stiffness will be assessed at study inception and completion. The Optimal ESRD Treatment study should shed light on the complicated interplay of anemia and CKD-MBD and on the feasibility of clinical trials in this domain. The study results are expected in the spring of 2017

Sudden Death in End Stage Renal Disease : Comparing Hemodialysis versus Peritoneal Dialysis

Background/Aims: This study aimed to evaluate total and sudden death (SD) in a cohort of dialysis patients, comparing hemodialysis (HD) vs. peritoneal dialysis (PD). Methods: This is a multicenter retrospective cohort study. Results: Deaths were 626 out of 1,823 in HD and 62 of 249 in PD patients. HD patients had a greater number of comorbidities (p < 0.05). PD patients had a lower risk of death than HD patients (p < 0.001); however, the advantage decreased with time (p < 0.001). Mortality predictors were left ventricular ejection fraction (LVEF) \ue2\u89\ua435%, older age, ischemic heart disease, diabetes mellitus, previous stroke, and atrial fibrillation (p < 0.03). SDs were 84:71 in HD and 13 in PD population (12.1 and 22.8% of all causes of death, respectively). A non-significant risk of SD among PD compared to HD patients was detected. SD predictors were older age, ischemic heart disease, and LVEF \ue2\u89\ua435% (p < 0.05). Conclusions: HD patients showed a greater presence of comorbidities and reduced survival compared to PD patients; however, the incidence of SD does not differ in the 2 populations. Video Journal Club "Cappuccino with Claudio Ronco" at http://www.karger.com/?doi=464347

Effects of soil type and adult size on mating propensity and reproductive output in two populations of the land snail Arianta arbustorum (Linnaeus)

Life-history traits in terrestrial gastropods may be influenced by both abiotic and biotic factors. This study examines the effects of soil type and adult size (shell volume) on mating propensity and female and male reproductive output (number and mass of eggs, number of sperm delivered and spermatophore mass) in individuals of the simultaneous hermaphrodite land snail Arianta arbustorum from two populations kept both on calcium-(Ca-)rich and Ca-poor soil. Snails from the two populations differed in adult size, relative shell growth, mating propensity and egg size. Furthermore, in both populations the number of egg batches deposited, egg size and spermatophore size scaled allometrically with shell volume, but not the total number of eggs produced and number of sperm delivered. Independent of population and shell size, the type of soil on which the snails were maintained influenced mating propensity, the total number of eggs produced and the mass of the albumen gland (another measure of female reproductive output). The mating propensity was higher and the total number of eggs produced was larger in snails kept on Ca-poor soil than in individuals reared on Ca-rich soil. This surprising finding could be explained by the fact that the Ca-poor soil used in the experiment still contained enough Ca to allow reproduction, and that the snails ingested Ca through the food consumed (lettuce grown on Ca-rich soil was available ad libitum). Moreover, the Ca-rich soil could contain minerals or (unknown) substances which discourage reproduction in A. arbustorum. Our study highlights the complexities faced when interpreting differences in the life history of gastropods. Explaining interpopulational differences in life-history patterns requires not only the understanding of the influence of snail origin, but also an understanding of the effects of shell size, substratum type (soil type), food and local climate