Spin Configuration in the 1/3 Magnetization Plateau of Azurite Determined by NMR

High magnetic field $^{63,65}$Cu NMR spectra were used to determine the local spin polarization in the 1/3 magnetization plateau of azurite, Cu$_3$(CO$_3$)$_2$(OH)$_2$, which is a model system for the distorted diamond antiferromagnetic spin-1/2 chain. The spin part of the hyperfine field of the Cu2 (dimer) sites is found to be field independent, negative and strongly anisotropic, corresponding to $\approx$10 % of fully polarized spin in a $d$-orbital. This is close to the expected configuration of the "quantum" plateau, where a singlet state is stabilized on the dimer. However, the observed non-zero spin polarization points to some triplet admixture, induced by strong asymmetry of the diamond bonds $J_1$ and $J_3$.Comment: Phys. Rev. Lett. 102, in press (2009

Pre-treatment high-sensitivity troponin T for the short-term prediction of cardiac outcomes in patients on immune checkpoint inhibitors

Background: Immune checkpoint inhibitors (ICIs) are an emerging option for several advanced metastatic cancers, but may have cardiotoxic effects. The prognostic value of high-sensitivity troponin T (hs-TnT) before treatment start has never been investigated. Materials and methods: Thirty consecutive patients underwent measurement of hs-TnT before starting ICI therapy (pembrolizumab, 23%; nivolumab, 12%; atezolizumab, 6%; durvalumab, 5%). The primary endpoint of cardiovascular death, stroke or transient ischaemic attack, pulmonary embolism and new-onset heart failure, and the secondary endpoint of progression of cardiac involvement according to the CARDIOTOX classification were evaluated after 3 months from the first cycle. Results: Patients (median age 68 years, 77% men, 13% with coronary artery disease, 90% current or former smokers, 67% overweight or obese and 43% hypertensive) had a median hs-TnT of 12 ng/L (interquartile interval 8-23). The primary endpoint occurred only in patients with hs-TnT ≥ 14 ng/L at baseline. Therefore, only patients who had hs-TnT ≥ 14 ng/L before the first cycle died had a stroke/TIA or new-onset HF. Furthermore, nine out of 13 patients with the secondary endpoint (progression of cardiac disease) had hs-TnT ≥ 14 ng/L before the first cycle (P =.012). AUC values were 0.909 for the primary endpoint and 0.757 for the secondary endpoint. The best cut-off was 14 ng/L for both the primary (100% sensitivity, 73% specificity) and secondary endpoints (sensitivity 75%, specificity 77%). Conclusions: In patients on ICIs, baseline hs-TnT predicts a composite cardiovascular endpoint and the progression of cardiac involvement at 3 months, with 14 ng/L as the best cut-off

COVID-19 and myocarditis: a systematic review and overview of current challenges

Myocardial inflammation in COVID-19 has been documented. Its pathogenesis is not fully elucidated, but the two main theories foresee a direct role of ACE2 receptor and a hyperimmune response, which may also lead to isolated presentation of COVID-19-mediated myocarditis. The frequency and prognostic impact of COVID-19-mediated myocarditis is unknown. This review aims to summarise current evidence on this topic. We performed a systematic review of MEDLINE and Cochrane Library (1/12/19–30/09/20). We also searched clinicaltrials.gov for unpublished studies testing therapies with potential implication for COVID-19-mediated cardiovascular complication. Eligible studies had laboratory confirmed COVID-19 and a clinical and/or histological diagnosis of myocarditis by ESC or WHO/ISFC criteria. Reports of 38 cases were included (26 male patients, 24 aged < 50 years). The first histologically proven case was a virus-negative lymphocytic myocarditis; however, biopsy evidence of myocarditis secondary to SARS-CoV-2 cardiotropism has been recently demonstrated. Histological data was found in 12 cases (8 EMB and 4 autopsies) and CMR was the main imaging modality to confirm a diagnosis of myocarditis (25 patients). There was a substantial variability in biventricular systolic function during the acute episode and in therapeutic regimen used. Five patients died in hospital. Cause-effect relationship between SARS-CoV-2 infection and myocarditis is difficult to demonstrate. However, current evidence demonstrates myocardial inflammation with or without direct cardiomyocyte damage, suggesting different pathophysiology mechanisms responsible of COVID-mediated myocarditis. Established clinical approaches should be pursued until future evidence support different actions. Large multicentre registries are advisable to elucidate further

Discharge FGF23 level predicts one year outcome in patients admitted with acute heart failure

Background: Patients with acute heart failure (AHF) show high levels of fibroblast growth factor-23 (FGF23) on admission. We examined if plasma FGF23 changes during an episode of AHF, and if FGF23 holds prognostic significance in this setting. Methods: Consecutive AHF patients were enrolled. Blood samples were collected on admission and at discharge. Patients were then followed for all-cause death or HF hospitalization. Results: Patients (n = 125; median age 76 years [interquartile interval 71–83], 63% men, left ventricular ejection fraction 35% [25%–56%]) had median admission FGF23 70 ng/L (47–100), N-terminal pro-B-type natriuretic peptide (NT-proBNP) 5844 ng/L (2,503-10,468), high-sensitivity troponin T (hs-TnT) 40 ng/L (25–72), and soluble suppression of tumorigenesis-2 (sST2) 26 ng/mL (17–37). While other biomarkers decreased, FGF23 increased by 15% from admission to discharge (p = 0.033), with a significant correlation with percent changes in estimated glomerular filtration rate (rho = 0.306, p = 0.001). Over a 12-month follow-up, 64 patients (51%) experienced the endpoint. They were more often men, older, with higher systolic pulmonary artery pressure (sPAP), higher NT-proBNP, hs-TnT and discharge FGF23. The best FGF23 cut-off at discharge from receiver operating characteristics analysis was 78 ng/L. Both discharge FGF23 and the 78 ng/L cut-off independently predicted outcome in models including gender, sPAP, age, and 1) admission NT-proBNP, 2) discharge NT-proBNP, 3) admission NT-proBNP and hs-TnT, 4) discharge NT-proBNP and hs-TnT. The 78 ng/L cut-off also refined risk reclassification. Conclusions: During an AHF episode, FGF23 increases from admission to discharge, and patients with higher discharge FGF23 have a higher risk of worse outcome

High energy photoelectron diffraction: model calculations and future possibilities

We discuss the theoretical modelling of x-ray photoelectron diffraction (XPD) with hard x-ray excitation at up to 20 keV, using the dynamical theory of electron diffraction to illustrate the characteristic aspects of diffraction patterns resulting from such localized emission sources in a multi-layer crystal. We show via dynamical calculations for diamond, Si, and Fe that the dynamical theory well predicts available current data for lower energies around 1 keV, and that the patterns for energies above about 1 keV are dominated by Kikuchi bands which are created by the dynamical scattering of electrons from lattice planes. The origin of the fine structure in such bands is discussed from the point of view of atomic positions in the unit cell. The profiles and positions of the element-specific photoelectron Kikuchi bands are found to be sensitive to lattice distortions (e.g. a 1% tetragonal distortion) and the position of impurities or dopants with respect to lattice sites. We also compare the dynamical calculations to results from a cluster model that is more often used to describe lower-energy XPD. We conclude that hard XPD (HXPD) should be capable of providing unique bulk-sensitive structural information for a wide variety of complex materials in future experiments.Comment: 29 pages, 13 figure

Dynamic and thermodynamic properties of the generalised diamond chain model for azurite

The natural mineral azurite Cu3(CO3)2(OH)2 is an interesting spin-1/2 quantum antiferromagnet. Recently, a generalised diamond chain model has been established as a good description of the magnetic properties of azurite with parameters placing it in a highly frustrated parameter regime. Here we explore further properties of this model for azurite. First, we determine the inelastic neutron scattering spectrum in the absence of a magnetic field and find good agreement with experiments, thus lending further support to the model. Furthermore, we present numerical data for the magnetocaloric effect and predict that strong cooling should be observed during adiabatic (de)magnetisation of azurite in magnetic fields slightly above 30T. Finally, the presence of a dominant dimer interaction in azurite suggests the use of effective Hamiltonians for an effective low-energy description and we propose that such an approach may be useful to fully account for the three-dimensional coupling geometry.Comment: 19 pages, 6 figures; to appear in: J. Phys.: Condens. Matter (special issue on geometrically frustrated magnetism

Predictors of adverse prognosis in COVID-19: A systematic review and meta-analysis

Background: Identification of reliable outcome predictors in coronavirus disease 2019 (COVID-19) is of paramount importance for improving patient's management. Methods: A systematic review of literature was conducted until 24 April 2020. From 6843 articles, 49 studies were selected for a pooled assessment; cumulative statistics for age and sex were retrieved in 587 790 and 602 234 cases. Two endpoints were defined: (a) a composite outcome including death, severe presentation, hospitalization in the intensive care unit (ICU) and/or mechanical ventilation; and (b) in-hospital mortality. We extracted numeric data on patients’ characteristics and cases with adverse outcomes and employed inverse variance random-effects models to derive pooled estimates. Results: We identified 18 and 12 factors associated with the composite endpoint and death, respectively. Among those, a history of CVD (odds ratio (OR) = 3.15, 95% confidence intervals (CIs) 2.26-4.41), acute cardiac (OR = 10.58, 5.00-22.40) or kidney (OR = 5.13, 1.78-14.83) injury, increased procalcitonin (OR = 4.8, 2.034-11.31) or D-dimer (OR = 3.7, 1.74-7.89), and thrombocytopenia (OR = 6.23, 1.031-37.67) conveyed the highest odds for the adverse composite endpoint. Advanced age, male sex, cardiovascular comorbidities, acute cardiac or kidney injury, lymphocytopenia and D-dimer conferred an increased risk of in-hospital death. With respect to the treatment of the acute phase, therapy with steroids was associated with the adverse composite endpoint (OR = 3.61, 95% CI 1.934-6.73), but not with mortality. Conclusions: Advanced age, comorbidities, abnormal inflammatory and organ injury circulating biomarkers captured patients with an adverse clinical outcome. Clinical history and laboratory profile may then help identify patients with a higher risk of in-hospital mortality

Psychological Distress Is More Prevalent in Fertile Age and Premenopausal Women With PCOS Symptoms : 15-Year Follow-Up

Context: Polycystic ovary syndrome (PCOS) is associated with increased psychological distress, obesity and hyperandrogenism being suggested as key promoters. Objectives: To investigate the prevalence of anxiety/depression and their coexistence in women with PCOS/PCOS-related symptoms at ages 31 and 46. The roles of obesity, hyperandrogenism, and awareness of PCOS on psychological distress were also assessed. Design: Population-based follow-up. Setting: Northern Finland Birth Cohort 1966 with 15-year follow-up. Participants: At age 31, a questionnaire-based screening for oligoamenorrhea (OA) and hirsutism (H): 2188 asymptomatic (controls), 331 OA, 323 H, and 125 OA plus H (PCOS). Follow-up at age 46: 1576 controls, 239 OA, 231 H, and 85 PCOS. Interventions: Questionnaire-based screening for anxiety and depression symptoms (Hopkins Symptom Checklist-25) and previously diagnosed/treated depression at ages 31 and 46. Body mass index (BMI), serum testosterone/free androgen index, and awareness of polycystic ovaries/PCOS on psychological distress were also assessed. Main Outcomes: Population-based prevalence of anxiety and/or depression in women with PCOS/PCOS-related symptoms at ages 31 and 46. Results: Anxiety and/or depression symptoms, their coexistence, and rate of depression were increased at ages 31 and 46 in women with PCOS or isolated H compared with controls. High BMI or hyperandrogenism did not associate with increased anxiety or depression symptoms. The awareness of PCOS was associated with increased anxiety. Conclusions: Women with PCOS or isolated H present more often with anxiety and/or depression symptoms and their coexistence compared with controls. High BMI or hyperandrogenism did not provoke psychological distress in PCOS. The awareness of PCOS increased anxiety but did not associate with severe anxiety or depression.Peer reviewe

Psychological Distress Is More Prevalent in Fertile Age and Premenopausal Women With PCOS Symptoms : 15-Year Follow-Up

Context: Polycystic ovary syndrome (PCOS) is associated with increased psychological distress, obesity and hyperandrogenism being suggested as key promoters. Objectives: To investigate the prevalence of anxiety/depression and their coexistence in women with PCOS/PCOS-related symptoms at ages 31 and 46. The roles of obesity, hyperandrogenism, and awareness of PCOS on psychological distress were also assessed. Design: Population-based follow-up. Setting: Northern Finland Birth Cohort 1966 with 15-year follow-up. Participants: At age 31, a questionnaire-based screening for oligoamenorrhea (OA) and hirsutism (H): 2188 asymptomatic (controls), 331 OA, 323 H, and 125 OA plus H (PCOS). Follow-up at age 46: 1576 controls, 239 OA, 231 H, and 85 PCOS. Interventions: Questionnaire-based screening for anxiety and depression symptoms (Hopkins Symptom Checklist-25) and previously diagnosed/treated depression at ages 31 and 46. Body mass index (BMI), serum testosterone/free androgen index, and awareness of polycystic ovaries/PCOS on psychological distress were also assessed. Main Outcomes: Population-based prevalence of anxiety and/or depression in women with PCOS/PCOS-related symptoms at ages 31 and 46. Results: Anxiety and/or depression symptoms, their coexistence, and rate of depression were increased at ages 31 and 46 in women with PCOS or isolated H compared with controls. High BMI or hyperandrogenism did not associate with increased anxiety or depression symptoms. The awareness of PCOS was associated with increased anxiety. Conclusions: Women with PCOS or isolated H present more often with anxiety and/or depression symptoms and their coexistence compared with controls. High BMI or hyperandrogenism did not provoke psychological distress in PCOS. The awareness of PCOS increased anxiety but did not associate with severe anxiety or depression.Peer reviewe