Epigenetic Effects of Healthy Foods and Lifestyle Habits from the Southern European Atlantic Diet Pattern: A Narrative Review

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Optical aberrations in the mouse eye

PURPOSE: The mouse eye is a widely used model for retinal disease and has potential to become a model for myopia. Studies of retinal disease will benefit from imaging the fundus in vivo. Experimental models of myopia often rely on manipulation of the visual experience. In both cases, knowledge of the optical quality of the eye, and in particular, the retinal image quality degradation imposed by the ocular aberrations is essential. In this study, we measured the ocular aberrations in the wild type mouse. METHODS: Twelve eyes from six four-week old black C57BL/6 wild type mice were studied. Measurements were done on awake animals, one being also measured under anesthesia for comparative purposes. Ocular aberrations were measured using a custom-built Hartmann-Shack system (using 680-nm illumination). Wave aberrations are reported up to fourth order Zernike polynomials. Spherical equivalent and astigmatism were obtained from the 2nd order Zernike terms. Modulation Transfer Functions (MTF) were estimated for the best focus, and through-focus, to estimate depth-of-focus. All reported data were for 1.5-mm pupils. RESULTS: Hartmann-Shack refractions were consistently hyperopic (10.12+/-1.41 D, mean and standard deviation) and astigmatism was present in many of the eyes (3.64+/-3.70 D, on average). Spherical aberration was positive in all eyes (0.15+/-0.07 microm) and coma terms RMS were significantly high compared to other Zernike terms (0.10+/-0.03 microm). MTFs estimated from wave aberrations show a modulation of 0.4 at 2c/deg, for best focus (and 0.15 without cancelling the measured defocus). For that spatial frequency, depth-of-focus estimated from through-focus modulation data using the Rayleigh criterion was 6D. Aberrations in the eye of one anesthetized mouse were higher than in the same eye of the awake animal. CONCLUSIONS: Hyperopic refractions in the mouse eye are consistent with previous retinoscopic data. The optics of the mouse eye is far from being diffraction-limited at 1.5-mm pupil, with significant amounts of spherical aberration and coma. However, estimates of MTFs from wave aberrations are higher than previously reported using a double-pass technique, resulting in smaller depth-of-field predictions. Despite the large degradation imposed by the aberrations these are lower than the amount of aberrations typically corrected by available correction techniques (i.e., adaptive optics). On the other hand, aberrations do not seem to be the limiting factor in the mouse spatial resolution. While the mouse optics are much more degraded than in other experimental models of myopia, its tolerance to large amounts of defocus does not seem to be determined entirely by the ocular aberrations.     

Iliotibial band reconstruction with allograft fasciae latae tissue: Imaging aspects of a novel surgical technique

We describe a unique case of 43-year-old male who presented with a persistent lateral knee pain caused by impingement between a femoral surgical screw and the iliotibial band, which was treated with surgical resection of the screw debris. The patient had reincidence of the symptoms and a magnetic resonance showed a wide and unrepairable tear of the iliotibial band, which was treated with interposition of a folded fasciae latae allograf. After the procedure, the patient had excellent clinical results and imaging evaluation showed progressive allograft integration. This case highlights the imaging findings and surgical aspects of an iliotibial band reconstruction, a novel surgical procedure that could be considered in patients with an unrepairable iliotibial band injury.     

Water dissociation at the water–rutile TiO2(110) interface from ab initio-based deep neural network simulations

The interaction of water with TiO₂ surfaces is of crucial importance in various scientific fields and applications, from photocatalysis for hydrogen production and the photooxidation of organic pollutants to self-cleaning surfaces and bio-medical devices. In particular, the equilibrium fraction of water dissociation at the TiO₂–water interface has a critical role in the surface chemistry of TiO₂, but is difficult to determine both experimentally and computationally. Among TiO₂ surfaces, rutile TiO₂(110) is of special interest as the most abundant surface of TiO₂’s stable rutile phase. While surface-science studies have provided detailed information on the interaction of rutile TiO₂(110) with gas-phase water, much less is known about the TiO₂(110)–water interface, which is more relevant to many applications. In this work, we characterize the structure of the aqueous TiO₂(110) interface using nanosecond timescale molecular dynamics simulations with ab initio-based deep neural network potentials that accurately describe water/TiO₂(110) interactions over a wide range of water coverages. Simulations on TiO₂(110) slab models of increasing thickness provide insight into the dynamic equilibrium between molecular and dissociated adsorbed water at the interface and allow us to obtain a reliable estimate of the equilibrium fraction of water dissociation. We find a dissociation fraction of 22 ± 6% with an associated average hydroxyl lifetime of 7.6 ± 1.8 ns. These quantities are both much larger than corresponding estimates for the aqueous anatase TiO₂(101) interface, consistent with the higher water photooxidation activity that is observed for rutile relative to anatase.

Water is ubiquitous in the environment and its interaction with metal oxide surfaces has a key role in processes that range from wetting, dissolution, and corrosion to photocatalytic reactions (1, 2). The relative stability of molecularly vs. dissociatively adsorbed species can be of critical importance in these processes and has been intensely debated even for the simplest, low-index surfaces.One oxide surface of major fundamental and practical interest is rutile TiO₂(110) (R-110 in the following), that is widely considered the prototypical metal oxide surface (3–9). Extensive investigations of gas-phase water adsorption on R-110 have established that oxygen vacancies—the most common defects on this surface—dissociate water and become hydroxylated (10–13), while molecularly adsorbed water is only ~0.035 eV more stable than dissociated water at regular surface sites (14). Moreover, a ~20% fraction of dissociated water has been reported for one adsorbed monolayer on R-110 at T = 210 K (15). However, information is scarce for the interface between R-110 and liquid water, which is the system more relevant to photocatalysis and other practical applications.Experiments based on synchrotron X-ray diffraction revealed water layering with partial dissociation of the adsorbed water on the R-110 surface (16–18). In other experiments, various ordered structures with (2 × 1) periodicity at the interface were reported, either on R-110 in water (19) or after exposure to liquid water (20), but such structures were found to be induced by adsorbed organic contaminants rather than interfacial water in subsequent studies (21). On the theoretical side, density functional theory (DFT)-based ab initio molecular dynamics (AIMD) simulations reported that water remains intact at the interface with defect-free R-110 (22), but this prediction could not explain the results of X-ray experiments (18).While AIMD has provided invaluable information on the interaction of water with metal oxide surfaces (9, 23, 24), the length and time scales accessible by ab initio simulations are often insufficient to characterize the properties of aqueous oxide interfaces (25–28). For example, the duration of AIMD simulations was found to be too short to allow a reliable prediction of the equilibrium fraction of water dissociation at the aqueous anatase TiO₂ (101) (A-101) interface (25). To overcome these limitations, computationally efficient interatomic potentials with the accuracy of ab initio electronic structure methods are needed. As shown by several recent studies, this goal can be achieved using ab initio-based deep neural networks (DNNs) to represent the potential energy surface of the system of interest (29–34). Still, constructing a general DNN potential for heterogeneous systems can be challenging (35), and in fact relatively few applications to aqueous metal oxide interfaces have so far been reported (27, 35–37).In this work, we have developed and applied ab initio-based DNNs to elucidate the structure and average degree of water dissociation at the aqueous R-110 interface. Specifically, we used the “Deep Potential” (DP) scheme by Zhang et al. (30, 31) to construct a DNN potential that accurately reproduces the DFT results for both isolated gas-phase water molecules and liquid water interacting with defect-free R-110. For this surface, an additional difficulty is the significant dependence of the DFT predictions on the R-110 slab thickness (22, 38). To address this issue and be able to extrapolate the results to large slab thickness, the DP was trained on slab models of different numbers of layers and later used to run nanosecond timescale simulations of the aqueous interfaces of several different, 4 to 16 O-Ti-O trilayers thick, R-110 slabs. From these simulations, we estimated an equilibrium water dissociation fraction of 22 ± 6% and, correspondingly, a free energy difference between dissociatively and molecularly adsorbed water at the R-110/water interface of 0.040 ± 0.007 eV. Comparison of these estimates for R-110 to analogous results for aqueous A-101 (37) shows differences in the behavior of interfacial water that can significantly affect the functional properties of these two systems.     

A Comparison of the Effects of Oral Glutamine Dipeptide,Glutamine, and Alanine on Blood Amino Acid Availability in Rats Submitted to Insulin-Induced Hypoglycemia

We compared the effects of oral administration of high-dose or low-dose glutamine dipeptide (GDP), alanine (ALA), glutamine (GLN), and ALA + GLN on the blood availability of amino acids in rats submitted to insulin-induced hypoglycemia (IIH). Insulin detemir (1 U/kg) was intraperitoneally injected to produce IIH; this was followed by oral administration of GDP, GLN + ALA, GLN, or ALA. We observed higher blood levels of GLN, 30 min after oral administration of high-dose GDP (1000 mg/kg) than after administration of ALA (381 mg/kg) + GLN (619 mg/kg), GLN (619 mg/kg), or ALA (381 mg/kg). However, we did not observe the same differences after oral administration of low-dose GDP (100 mg/kg) compared with ALA (38.1 mg/kg) + GLN (61.9 mg/kg), GLN (61.9 mg/kg), or ALA (38.1 mg/kg). We also observed less liver catabolism of GDP compared to ALA and GLN. In conclusion, high-dose GDP promoted higher blood levels of GLN than oral ALA + GLN, GLN, or ALA. Moreover, the lower levels of liver catabolism of GDP, compared to ALA or GLN, contributed to the superior performance of high-dose GDP in terms of blood availability of GLN.     

Correlation between Electrocardiographic Features and Mechanical Dyssynchrony in Heart Failure Patients with Left Bundle Branch Block

Background: Few electrocardiographic parameters beyond the QRS duration were studied with regard to the correlation with mechanical dyssynchrony. This study aims to analyze the correlation between electrocardiographic parameters and mechanical dyssynchrony in patients with symptomatic heart failure (HF) and left bundle branch block (LBBB). Methods: Patients with HF, ejection fraction ≤ 35%, and QRS interval ≥ 120 ms with a LBBB were prospectively studied. We analyzed the correlation between electrocardiographic parameters (QRS duration, R voltage in limb leads, S voltage in precordial leads, Sokolow and Cornell indexes, QRS axis deviation, and QRS notches in lateral and inferior leads) and mechanical dyssynchrony measured by tissue Doppler imaging (TDI). Results: A group of 50 patients were studied, 60% male, 78% with nonischemic cardiomyopathy, NYHA Class III–IV (86%), and ejection fraction of 0.22 ± 0.6. Intra‐ and interventricular dyssynchrony occurred in 68% and 74% of patients, respectively. The S amplitude in precordial leads and the Sokolow and Cornel indexes show a weak correlation with the degree of dyssynchrony. In the patients with QRS notching in the lateral and inferior leads, we observed significantly greater prevalence of intraventricular dyssynchrony, with sensitivity and specificity of 85% and 56%, respectively, for notches in lateral leads. The QRS duration presents moderate correlation with the degree of both intraventricular (r = 0.48) and interventricular dyssynchrony (r = 0.46). Conclusion: The following electrocardiographic parameters were related to the degree of mechanical dyssynchrony: QRS duration and notches in QRS. In addition, the patients tend to have highest S amplitude in precordial leads. Ann Noninvasive Electrocardiol 2011;16(1):41–48