Assessment of lung ventilation of premature infants with bronchopulmonary dysplasia at 1.5 Tesla using phase-resolved functional lung magnetic resonance imaging.

BACKGROUND: The most common chronic complication of preterm birth is bronchopulmonary dysplasia (BPD), widely referred to as chronic lung disease of prematurity. All current definitions rely on characterizing the disease based on respiratory support level and do not provide full understanding of the underlying cardiopulmonary pathophysiology. OBJECTIVE: To evaluate a rapid functional lung imaging technique in premature infants and to quantitate pulmonary ventilation using 1.5 Tesla magnetic resonance imaging (MRI). MATERIALS AND METHODS: We conducted a prospective MRI study of 12 premature infants in the neonatal intensive care unit (NICU) using the phase resolved functional lung MRI technique to calculate pulmonary ventilation parameters in preterm infants with and without BPD grade 0/1 (n = 6) and grade 2/3 (n = 6). RESULTS: The total ventilation defect percentage showed a significant difference between groups (16.0% IQR (11.0%,18%) BPD grade 2/3 vs. 8.0% IQR (4.5%,9.0%) BPD grade 0/1, p = 0.01). CONCLUSION: Phase-resolved functional lung MRI is feasible for assessment of ventilation defect percentages in preterm infants and shows regional variation in localized lung function in this population.

Caregivers' perception of adults with Down syndrome willingness to participate in research.

BACKGROUND: Historically, individuals with Down syndrome have been excluded from clinical research. Our objective was to assess the degree of interest adults with Down syndrome have in participating in research from the perspective of the caregivers who care for them. METHODS: We conducted an online survey of N = 390 caregivers of adults with Down syndrome and asked about interest in research participation and demographics. RESULTS: Caregivers were mostly family members, older than 55 years, and White. Caregivers reported that the adult with Down syndrome that they cared for would be more comfortable participating in research that was physiological, such as research involving fit bits (70.2% would participate), exercise (63.3%) or diet apps (53.9%), whereas they would be less likely to participate in clinical trials involving more invasive procedures such as injections (10.9%) and laboratory exams like MRIs (32.0%). We found little difference by age or gender of the adult with Down syndrome or by caregiver education level. CONCLUSIONS: Our survey identified high interest for less invasive studies, illustrating acceptability of observational and lifestyle studies. More effort may be needed to understand fear and barriers to participation and to create tools and methods to increase interest in more invasive studies.

Impact of the 2017 American Heart Association and American College of Cardiology hypertension guideline in aged individuals.

OBJECTIVES: The AHA/ACC-2017 hypertension guideline recommends an age-independent target blood pressure (BP) of less than 130/80 mmHg. In an elderly cohort without established cardiovascular disease (CVD) at baseline, we determined the impact of this guideline on the prevalence of hypertension and associated CVD risk. METHODS: Nineteen thousand, one hundred and fourteen participants aged at least 65 years from the ASPirin in Reducing Events in the Elderly (ASPREE) study were grouped by baseline BP: 'pre-2017 hypertensive' (BP ≥140/90 mmHg and/or on antihypertensive drugs); 'reclassified hypertensive' (normotensive by pre-2017 guidelines; hypertensive by AHA/ACC-2017 guideline), and 'normotensive' (BP <130 and <80 mmHg). For each group, we evaluated CVD risk factors, predicted 10-year CVD risk using the Atherosclerotic Cardiovascular Disease (ASCVD) risk equation, and reported observed CVD event rates during a median 4.7-year follow-up. RESULTS: Overall, 74.4% (14 213/19 114) were 'pre-2017 hypertensive'; an additional 12.3% (2354/19 114) were 'reclassified hypertensive' by the AHA/ACC-2017 guideline. Of those 'reclassified hypertensive', the majority (94.5%) met criteria for antihypertensive treatment although 29% had no other traditional CVD risk factors other than age. Further, a relatively lower mean 10-year predicted CVD risk (18% versus 26%, P < 0.001) and lower CVD rates (8.9 versus 12.1/1000 person-years, P = 0.01) were observed in 'reclassified hypertensive' compared with 'pre-2017 hypertensive'. Compared with 'normotensive', a hazard ratio (95% confidence interval) for CVD events of 1.60 (1.26-2.02) for 'pre-2017 hypertensive' and 1.26 (0.93-1.71) for 'reclassified hypertensive' was observed. CONCLUSION: Applying current CVD risk calculators in the elderly 'reclassified hypertensive', as a result of shifting the BP threshold lower, increases eligibility for antihypertensive treatment but documented CVD rates remain lower than hypertensive patients defined by pre2017 BP thresholds.

Resonantly Interacting Fermi-Fermi Mixture of

We report on the realization of a Fermi-Fermi mixture of ultracold atoms that combines mass imbalance, tunability, and collisional stability. In an optically trapped sample of ^{161}Dy and ^{40}K, we identify a broad Feshbach resonance centered at a magnetic field of 217 G. Hydrodynamic expansion profiles in the resonant interaction regime reveal a bimodal behavior resulting from mass imbalance. Lifetime studies on resonance show a suppression of inelastic few-body processes by orders of magnitude, which we interpret as a consequence of the fermionic nature of our system. The resonant mixture opens up intriguing perspectives for studies on novel states of strongly correlated fermions with mass imbalance.

Accurate Determination of the Dynamical Polarizability of Dysprosium.

We report a measurement of the dynamical polarizability of dysprosium atoms in their electronic ground state at the optical wavelength of 1064 nm, which is of particular interest for laser trapping experiments. Our method is based on collective oscillations in an optical dipole trap, and reaches unprecedented accuracy and precision by comparison with an alkali atom (potassium) as a reference species. We obtain values of 184.4(2.4) and 1.7(6) a.u. for the scalar and tensor polarizability, respectively. Our experiments have reached a level that permits meaningful tests of current theoretical descriptions and provides valuable information for future experiments utilizing the intriguing properties of heavy lanthanide atoms.

ASPREE-D: Aspirin for the prevention of depression in the elderly.

BACKGROUND: Not only is depression associated with increased inflammation but inflammation is a risk factor for the genesis of depression. Many of the environmental risk factors for depression are transduced through inflammatory signaling. Anti-inflammatory agents show promise for the management of depression in preclinical, epidemiological, and early clinical studies. This opens the door to the potential for anti-inflammatory agents to treat and prevent depression. There are no evidence-based pharmacotherapies for depression prevention. METHOD: ASPREE-D, aspirin in the prevention of depression in the elderly, is a sub study of ASPREE, which explores the potential of aspirin to prevent a range of inflammation related disorders in the elderly. With a sample size of 19,114, and a duration of 5 years, this placebo controlled study will be one of the largest randomized controlled trials in psychiatry and will provide definitive evidence on the ability of aspirin to prevent depression. RESULTS: This paper presents the rationale for the study and presents a summary of the study design. CONCLUSIONS: ASPREE-D may not only define novel therapy but will provide mechanistic proof of concept of the role of inflammation in depression.

Ultracold Dipolar Molecules Composed of Strongly Magnetic Atoms.

In a combined experimental and theoretical effort, we demonstrate a novel type of dipolar system made of ultracold bosonic dipolar molecules with large magnetic dipole moments. Our dipolar molecules are formed in weakly bound Feshbach molecular states from a sample of strongly magnetic bosonic erbium atoms. We show that the ultracold magnetic molecules can carry very large dipole moments and we demonstrate how to create and characterize them, and how to change their orientation. Finally, we confirm that the relaxation rates of molecules in a quasi-two-dimensional geometry can be reduced by using the anisotropy of the dipole-dipole interaction and that this reduction follows a universal dipolar behavior.

Reaching Fermi degeneracy via universal dipolar scattering.

We report on the creation of a degenerate dipolar Fermi gas of erbium atoms. We force evaporative cooling in a fully spin-polarized sample down to temperatures as low as 0.2 times the Fermi temperature. The strong magnetic dipole-dipole interaction enables elastic collisions between identical fermions even in the zero-energy limit. The measured elastic scattering cross section agrees well with the predictions from the dipolar scattering theory, which follow a universal scaling law depending only on the dipole moment and on the atomic mass. Our approach to quantum degeneracy proceeds with very high cooling efficiency and provides large atomic densities, and it may be extended to various dipolar systems.

Anisotropic relaxation dynamics in a dipolar Fermi gas driven out of equilibrium.

We report on the observation of a large anisotropy in the rethermalization dynamics of an ultracold dipolar Fermi gas driven out of equilibrium. Our system consists of an ultracold sample of strongly magnetic 167Er fermions, spin polarized in the lowest Zeeman sublevel. In this system, elastic collisions arise purely from universal dipolar scattering. Based on cross-dimensional rethermalization experiments, we observe a strong anisotropy of the scattering, which manifests itself in a large angular dependence of the thermal relaxation dynamics. Our result is in good agreement with recent theoretical predictions. Furthermore, we measure the rethermalization rate as a function of temperature for different angles and find that the suppression of collisions by Pauli blocking is not influenced by the dipole orientation.

Bose-Einstein condensation of erbium.

We report on the achievement of Bose-Einstein condensation of erbium atoms and on the observation of magnetic Feshbach resonances at low magnetic fields. By means of evaporative cooling in an optical dipole trap, we produce pure condensates of 168Er, containing up to 7×10(4) atoms. Feshbach spectroscopy reveals an extraordinary rich loss spectrum with six loss resonances already in a narrow magnetic-field range up to 3 G. Finally, we demonstrate the application of a low-field Feshbach resonance to produce a tunable dipolar Bose-Einstein condensate and we observe its characteristic d-wave collapse.

Metastability and coherence of repulsive polarons in a strongly interacting Fermi mixture.

Ultracold Fermi gases with tunable interactions provide a test bed for exploring the many-body physics of strongly interacting quantum systems. Over the past decade, experiments have investigated many intriguing phenomena, and precise measurements of ground-state properties have provided benchmarks for the development of theoretical descriptions. Metastable states in Fermi gases with strong repulsive interactions represent an exciting area of development. The realization of such systems is challenging, because a strong repulsive interaction in an atomic quantum gas implies the existence of a weakly bound molecular state, which makes the system intrinsically unstable against decay. Here we use radio-frequency spectroscopy to measure the complete excitation spectrum of fermionic (40)K impurities resonantly interacting with a Fermi sea of (6)Li atoms. In particular, we show that a well-defined quasiparticle exists for strongly repulsive interactions. We measure the energy and the lifetime of this 'repulsive polaron', and probe its coherence properties by measuring the quasiparticle residue. The results are well described by a theoretical approach that takes into account the finite effective range of the interaction in our system. We find that when the effective range is of the order of the interparticle spacing, there is a substantial increase in the lifetime of the quasiparticles. The existence of such a long-lived, metastable many-body state offers intriguing prospects for the creation of exotic quantum phases in ultracold, repulsively interacting Fermi gases.

Impact of body mass index on diastolic function in patients with normal left ventricular ejection fraction.

BACKGROUND: Obesity is a major public health epidemic and is associated with increased risk of heart failure and mortality. We evaluated the impact of body mass index (BMI) on the prevalence of diastolic dysfunction (DD). METHODS: We reviewed clinical records and echocardiogram of patients with baseline echocardiogram between 1996 and 2005 that showed normal left ventricular ejection fraction (LVEF). Diastolic function was labeled as normal, stage 1, stage 2 or stage 3/4 dysfunction. Patients were categorized as normal weight (BMI <25 kg m(-2)), overweight (25-29.9 kg m(-2)), obese (30-39.9 kg m(-2)) and morbidly obese (40 kg m(-2)). Multivariable ordinal and ordinary logistic regression were performed to identify factors associated with DD, and evaluate the independent relationship of BMI with DD. RESULTS: The cohort included 21 666 patients (mean (s.d.) age, 57.1 (15.1); 55.5% female). There were 7352 (33.9%) overweight, 5995 (27.6%) obese and 1616 (7.4%) morbidly obese patients. Abnormal diastolic function was present in 13 414 (61.9%) patients, with stage 1 being the most common. As BMI increased, the prevalence of normal diastolic function decreased (P<0.0001). Furthermore, there were 1733 patients with age <35 years; 460 (26.5%) and 407 (23.5%) were overweight and obese, respectively, and had higher prevalence of DD (P<0.001). Using multivariable logistic regression, BMI remained significant in both ordinal (all stages of diastolic function) and binary (normal versus abnormal). Also, obesity was associated with increased odds of DD in all patients and those aged <35 years. CONCLUSIONS: In patients with normal LVEF, higher BMI was independently associated with worsening DD.

Universality of the three-body parameter for Efimov states in ultracold cesium.

We report on the observation of triatomic Efimov resonances in an ultracold gas of cesium atoms. Exploiting the wide tunability of interactions resulting from three broad Feshbach resonances in the same spin channel, we measure magnetic-field dependent three-body recombination loss. The positions of the loss resonances yield corresponding values for the three-body parameter, which in universal few-body physics is required to describe three-body phenomena and, in particular, to fix the spectrum of Efimov states. Our observations show a robust universal behavior with a three-body parameter that stays essentially constant.

Gastric motor disturbances in patients with idiopathic rapid gastric emptying.

BACKGROUND: The mechanisms of 'idiopathic' rapid gastric emptying, which are associated with functional dyspepsia and functional diarrhea, are not understood. Our hypotheses were that increased gastric motility and reduced postprandial gastric accommodation contribute to rapid gastric emptying. METHODS: Fasting and postprandial (300kcal nutrient meal) gastric volumes were measured by magnetic resonance imaging (MRI) in 20 healthy people and 17 with functional dyspepsia; seven had normal and 10 had rapid gastric emptying. In 17 healthy people and patients, contractility was analyzed by spectral analysis of a time-series of gastric cross-sectional areas. Logistic regression models analyzed whether contractile parameters, fasting volume, and postprandial volume change could discriminate between health and patients with normal or rapid gastric emptying. KEY RESULTS: While upper gastrointestinal symptoms were comparable, patients with rapid emptying had a higher (P=0.002) body mass index than normal gastric emptying. MRI visualized propagating contractions at ∼3cpm in healthy people and patients. Compared with controls (0.32±0.04, Mean±SEM), the amplitude of gastric contractions in the entire stomach was higher (OR 4.1, 95% CI 1.2-14.0) in patients with rapid (0.48±0.06), but not normal gastric emptying (0.20±0.06). Similar differences were observed in the distal stomach. However, the propagation velocity, fasting gastric volume, and the postprandial volume change were not significantly different between patients and controls. CONCLUSIONS & INFERENCES: MRI provides a non-invasive and refined assessment of gastric volumes and contractility in humans. Increased gastric contractility may contribute to rapid gastric emptying in functional dyspepsia.

Hydrodynamic expansion of a strongly interacting fermi-fermi mixture.

We report on the expansion of an ultracold Fermi-Fermi mixture of (6)Li and (40)K under conditions of strong interactions controlled via an interspecies Feshbach resonance. We study the expansion of the mixture after release from the trap and, in a narrow magnetic-field range, we observe two phenomena related to hydrodynamic behavior. The common inversion of the aspect ratio is found to be accompanied by a collective effect where both species stick together and expand jointly despite of their widely different masses. Our work constitutes a major experimental step for a controlled investigation of the many-body physics of this novel strongly interacting quantum system.

Neutral and acidic oligosaccharides in Holstein-Friesian colostrum during the first 3 days of lactation measured by high performance liquid chromatography on a microfluidic chip and time-of-flight mass spectrometry.

Oligosaccharides (OS) from bovine milk are a class of bioactive molecules that are receiving increasing commercial attention for their potential health benefits. In the present work we measured, comprehensively and systematically, free milk OS in the colostrum of 7 Holstein-Friesian cows during the first 3 d of lactation in 12-h intervals by HPLC-chip/time-of-flight mass spectrometry to determine the biological variation of free milk OS in early lactation. The high sensitivity and resolution of the analytical technique made it possible to monitor all OS species, thus providing a comprehensive and quantitative analysis of OS variations during colostrum production. This study confirmed that although sialyllactose is the major OS in bovine colostrum, several neutral OS species are present in significant abundance even at the third day of lactation. Furthermore, variation in terms of OS species and relative abundances of OS between cows suggest individual animal variation. These variations are likely due to genetic factors because environmental factors such as nutrition, lactation number, and accommodation were the same for all cows. This investigation revealed that colostrum milk from Holstein-Friesian cows is a rich source of neutral and acidic OS for the food and pharmaceutical industries.

Effects of anemia and uremia and a combination of both on cardiovascular structures.

BACKGROUND: Cardiovascular complications are a major cause of morbidity and mortality in chronic renal failure (CRF) patients. Chronic anemia is a complication of CRF and a cardiovascular risk factor per se. It was the aim of the present study to clarify whether uremia and anemia are additive or supra-additive with respect to cardiovascular alterations. METHODS: Thirty SD rats were sham operated (sham) or subtotally nephrectomized (SNX). Both groups were subdivided into anemic (target hemoglobin 10 g/dl, by tail artery punctures) and untreated animals. Blood pressure, echocardiographic measurements and morphometric investigations were performed. The study was terminated after 16 weeks. RESULTS: Heart rate and blood pressure were similar in all groups. Anemia was comparable in sham+anemia and SNX+anemia. Left ventricular end-diastolic pressure was significantly higher in untreated SNX and SNX+anemia than in sham. Anemia and SNX caused comparable left ventricular hypertrophy (LVH), which was significantly higher in SNX+anemia. In sham animals, anemia induced thickening of intramyocardial arteries, which was significantly more pronounced in SNX with no additional effect of anemia. CONCLUSIONS: Experimentally, anemia and CRF induced LVH and intramyocardial arteriolar thickening. If both are combined, the increase in LVH is even more marked, whereas there are no additional effects on intramyocardial structural alterations.

Magnetically controlled exchange process in an ultracold atom-dimer mixture.

We report on the observation of an elementary exchange process in an optically trapped ultracold sample of atoms and Feshbach molecules. We can magnetically control the energetic nature of the process and tune it from endoergic to exoergic, enabling the observation of a pronounced threshold behavior. In contrast to relaxation to more deeply bound molecular states, the exchange process does not lead to trap loss. We find excellent agreement between our experimental observations and calculations based on the solutions of three-body Schrödinger equation in the adiabatic hyperspherical representation. The high efficiency of the exchange process is explained by the halo character of both the initial and final molecular states.

Variations in bovine milk oligosaccharides during early and middle lactation stages analyzed by high-performance liquid chromatography-chip/mass spectrometry.

Milk oligosaccharides (OS) are not only a source of nutrition for newborns, but also provide numerous important biological functions including the prevention of pathogen binding to the intestinal epithelium and serving as nutritive sources for beneficial bacteria. High-performance mass spectrometry and separation methods were used to evaluate changes of bovine milk oligosaccharides (bMO) in different lactation stages. Previously, 40 bMO were identified in bovine milk with many consisting of short oligomeric chains that were less complex than human milk oligosaccharides (hMO). The bMO are also significantly more anionic than hMO, with nearly 70% in measured abundances containing either N-acetylneuraminic acid or N-glycolylneuraminic acid, and no fucosylated OS. In this study, we examined factors that could affect the abundances of bMO including stage of lactation and breed. The total concentrations dropped rapidly in the first several days of lactation. Moreover, the anionic oligosaccharides (including N-glycolylneuraminic acid) decreased more rapidly compared with the neutral oligosaccharides.

Evidence for universal four-body states tied to an Efimov trimer.

We report on the measurement of four-body recombination rate coefficients in an atomic gas. Our results obtained with an ultracold sample of cesium atoms at negative scattering lengths show a resonant enhancement of losses and provide strong evidence for the existence of a pair of four-body states, which is strictly connected to Efimov trimers via universal relations. Our findings confirm recent theoretical predictions and demonstrate the enrichment of the Efimov scenario when a fourth particle is added to the generic three-body problem.