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Introduction: To echocardiographically evaluate a large number of apparently healthy Czechoslovakian wolfdogs (CWDs) to identify possible subclinical cardiac abnormalities and to generate reference intervals., Animals: One-hundred and seventeen apparently healthy client-owned CWDs., Materials and Methods: Standard two-dimensional, M-mode, and Doppler echocardiographic measurements were obtained on non-sedated, manually restrained standing dogs. Animals with no relevant echocardiographic abnormalities were used to generate reference intervals. Echocardiographic variables were compared between males and females and between dogs with and without mitral regurgitation (MR)., Results and Discussion: Among the 117 CWDs, 103 dogs were used to generate reference intervals. The 14 dogs with abnormalities had more than trivial MR (12 dogs), subaortic stenosis (one dog), and equivocal subaortic stenosis (one dog). The 44 males were heavier than 59 females (P<0.001) and had a larger maximum left atrial dimension (P=0.015), left ventricular internal dimension at end-diastole (P<0.001) and systole (P<0.001), and thicker interventricular septum thickness at end-diastole (P=0.016). A positive linear correlation was identified between bodyweight and aortic root and left atrial diameters and left ventricular dimensions and between age and aortic root and left atrial diameter and peak late transmitral flow velocity. A negative linear correlation was identified between age and peak early transmitral flow velocity and the ratio between peak early and late transmitral flow velocities. No differences in echocardiographic-derived cardiac dimensions were detected between healthy dogs and dogs with more than trivial MR., Conclusions: In this population of CWDs, subclinical cardiac abnormalities were uncommon, and they were mainly classified as MR., Competing Interests: Conflict of Interest Statement The authors do not have any conflict of interest to disclose., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Recently, researchers focused their attention on the use of polymeric bioresorbable vascular scaffolds (BVSs) as alternative to permanent metallic drug-eluting stents (DESs) for the treatment of atherosclerotic coronary arteries. Due to the different mechanical properties, polymeric stents, if compared to DESs, are characterized by larger strut size and specific design. It implies that during the crimping phase, BVSs undergo higher deformation and the packing of the struts, making this process potentially critical for the onset of damage. In this work, a computational study on the crimping procedure of a PLLA stent, inspired by the Absorb GT1 (Abbott Vascular) design, is performed, with the aim of evaluating how different strategies (loading steps, velocities and temperatures) can influence the results in terms of damage risk and final crimped diameter. For these simulations, an elastic-viscous-plastic model was adopted, based on experimental results, obtained from tensile testing of PLLA specimens loaded according to ad hoc experimental protocols. Furthermore, the results of these simulations were compared with those obtained by neglecting strain rate and temperature dependence in the material model (as often done in the literature), showing how this lead to significant differences in the prediction of the crimped diameter and internal stress state., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Here we evaluate the accuracy of prediction for eye, hair and skin pigmentation in a dataset of > 6500 individuals from Mexico, Colombia, Peru, Chile and Brazil (including genome-wide SNP data and quantitative/categorical pigmentation phenotypes - the CANDELA dataset CAN). We evaluated accuracy in relation to different analytical methods and various phenotypic predictors. As expected from statistical principles, we observe that quantitative traits are more sensitive to changes in the prediction models than categorical traits. We find that Random Forest or Linear Regression are generally the best performing methods. We also compare the prediction accuracy of SNP sets defined in the CAN dataset (including 56, 101 and 120 SNPs for eye, hair and skin colour prediction, respectively) to the well-established HIrisPlex-S SNP set (including 6, 22 and 36 SNPs for eye, hair and skin colour prediction respectively). When training prediction models on the CAN data, we observe remarkably similar performances for HIrisPlex-S and the larger CAN SNP sets for the prediction of hair (categorical) and eye (both categorical and quantitative), while the CAN sets outperform HIrisPlex-S for quantitative, but not for categorical skin pigmentation prediction. The performance of HIrisPlex-S, when models are trained in a world-wide sample (although consisting of 80% Europeans, https://hirisplex.erasmusmc.nl), is lower relative to training in the CAN data (particularly for hair and skin colour). Altogether, our observations are consistent with common variation of eye and hair colour having a relatively simple genetic architecture, which is well captured by HIrisPlex-S, even in admixed Latin Americans (with partial European ancestry). By contrast, since skin pigmentation is a more polygenic trait, accuracy is more sensitive to prediction SNP set size, although here this effect was only apparent for a quantitative measure of skin pigmentation. Our results support the use of HIrisPlex-S in the prediction of categorical pigmentation traits for forensic purposes in Latin America, while illustrating the impact of training datasets on its accuracy., (Copyright © 2021 Elsevier B.V. All rights reserved.)

To evaluate risks and complications of reoperations on heart valve prostheses, we reviewed data on 183 patients who underwent reoperation because of prosthetic valve malfunction. The incremental effect of the redo procedure on hospital mortality and morbidity was studied by comparing primary and reoperative procedures and analyzing a series of possible predisposing factors. Late survival after first and second reoperations was computed, and possible determinants of late mortality were examined. Overall operative mortality was 8.7%; emergency operation (p = 0.0001), previous thromboembolism (p = 0.05), and advanced New York Heart Association functional class (p = 0.031) were the independent determinants. In a series of 1,355 patients having primary or secondary isolated valve replacement, the redo procedure was a significant risk factor in the univariate analysis (p = 0.025) but not in the multivariate analysis except for the subset of patients having mitral valve replacement (p = 0.052). The postoperative course was quite complicated, as evidenced by the long mean stay in the intensive care unit (mean stay, 3.8 days; longer than 2 days for 26% of the survivors). Nevertheless, postoperative complications were not significantly greater after a redo procedure than after a primary operation. Actuarial survival at 7 years was 57.3% +/- 8%. A comparison with a nonhomogeneous series from our institution did not demonstrate significant differences. In the subset of 16 patients having a second reoperation, late survival was 37.8% +/- 16% at 2 years. Advanced New York Heart Association class (p = 0.0001), double prosthetic valve dysfunction (p = 0.003), and any indication other than primary tissue failure (p = 0.06) were determinants of late mortality.(ABSTRACT TRUNCATED AT 250 WORDS)

In order to test the effects of chronic lithium (Li) administration on learning and memory, 21 day old rats were subjected to different degrees of environmental stimulation (enriched condition, EC and impoverished condition, IC) with and without Li for 144 days. Li was administered with food (2.18 mEq/Kg weight/day). Average plasma Li concentration at the end of the experiment was 0.41 +/- 0.04 mu Eq/ml. Both Li treatment and the environmental condition showed an overall significant effect on the cortex/subcortex weight ratio and learning ability index, but not on AChE activity in occipital cortex. A similar pattern of brain Li distribution was observed in both EC-Li and IC-Li, with occipital cortex having the highest levels. Li tissue/protein/plasma ratio was higher in EC than in IC, in all the brain areas studied. Other organs (liver and kidney) did not show EC-IC differences in the tissue/protein/plasma Li ratio.

We studied 13 porcine bioprostheses removed from patients with endocarditis at our institute during the last 4.5 years. All bioprostheses had been removed at reoperation and were analyzed using anatomical and histological techniques. Each bioprosthesis was found to have developed rather constant lesions which were not related to the type of bioprosthesis. The stage of infection was not related to the duration of implantation. The presence of perivalvular abscesses was an ominous finding, often being the seat of persistent endocarditis. Our good clinical results of reoperation lead us to suggest that this be performed early once valvular or prosthetic malfunction is detected. Bioprostheses are, in our experience, the best choice in the surgical treatment of prosthetic valve endocarditis.

Clinical results with porcine bioprostheses were reviewed for 990 patients who underwent heart valve replacement from January, 1974, to December, 1980. Eight hundred and seventy-four Hancock, 283 Carpentier-Edwards, and 10 Liotta bioprostheses were used. In 23 patients, 26 mechanical prostheses were implanted as well. Overall operative mortality was 60 out of 990 (6.06%): 30 out of 506 (5.9%) for mitral valve replacement (MVR), 13 out of 287 (4.5%) for aortic valve replacement (AVR), 1 out of 4 (25%) for tricuspid valve replacement, 0 out of 2 for pulmonary valve replacement, and 16 out of 191 (8.4%) for multiple valve replacement. Cumulative follow-up covered 1,793 patient-years. (Actuarial survival at 7 years was 76.6 +/- 3% for MVR. At 6 years, it was 83.2 +/- 2.8% for AVR and 55 +/- 13.5% for multiple valve replacement.) Prosthesis-related survival at 7 years was 91.7 +/- 1.9% for MVR, and at 6 years, it was 96.6 +/- 1.5% for AVR and 95.1 +/- 2.2% for multiple valve replacement. Bioprosthesis survival, considering deaths or complications that led to reoperation as final events, was 84.2 +/- 3.7% at 7 years for mitral valves and 87.7 +/- 3.8% at 6 years for aortic valves. Emboli per 100 patient-years numbered 3.2 for MVR, 0.5 for AVR, and 1.6 for multiple valve replacement. Twenty-seven patients underwent reoperation, 12 for perivalvular leak, 5 for endocarditis, 6 for valve thrombosis, and 4 for primary tissue failure (linearized rates of 0.7, 0.3, 0.3, and 0.2% per patient-year, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)