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Sinus of Valsalva aneurysm rupture is a rare condition with a great potential for morbidity and mortality if not promptly diagnosed and managed. We present an unusual non-infected sinus of Valsalva aneurysm rupture in a 47-year-old female. This case report, a likely presentation of a late congenital heart defect, highlights the need for a high index of suspicion in a patient with atypical history of congestive cardiac failure.

Since its emergence in March 2020, the SARS-CoV-2 global pandemic has produced more than 116 million cases and 2.5 million deaths worldwide. Despite the enormous efforts carried out by the scientific community, no effective treatments have been developed to date. We applied a novel computational pipeline aimed to accelerate the process of identifying drug repurposing candidates which allows us to compare three-dimensional protein structures. Its use in conjunction with two in silico validation strategies (molecular docking and transcriptomic analyses) allowed us to identify a set of potential drug repurposing candidates targeting three viral proteins (3CL viral protease, NSP15 endoribonuclease, and NSP12 RNA-dependent RNA polymerase), which included rutin, dexamethasone, and vemurafenib. This is the first time that a topological data analysis (TDA)-based strategy has been used to compare a massive number of protein structures with the final objective of performing drug repurposing to treat SARS-CoV-2 infection.

Background and Aim: The coronavirus disease 2019 (COVID-19) pandemic has seen the cancellation of elective cardiac surgeries worldwide. Here we report the experience of a cardiac surgery unit in a developing country in response to the COVID-19 crisis., Methods: From 6th April to 12th June 2020, 58 patients underwent urgent or emergency cardiac surgery. Data was reviewed from a prospectively entered unit-maintained cardiac surgery database. To ensure safe delivery of care to patients, a series of strict measures were implemented which included: a parallel healthcare system maintaining a COVID-19 cold site, social isolation of patients for one to 2 weeks before surgery, polymerase chain reaction testing for COVID-19, 72 hours before surgery, discrete staff assigned only to cardiac surgical cases socially isolated for 2 weeks as necessary., Results: The mean age at surgery was 59.7 ± 11 years and 41 (70.7%) were male. Fifty-two patients were hypertensive (90%), and 32 were diabetic (55.2%). There were three emergency type A aortic dissections. Forty-seven patients underwent coronary artery bypass graft surgery with all but three performed off-pump. Fourteen cases required blood product transfusion. One patient had postoperative pneumonia associated with chronic obstructive pulmonary disease. The median length of stay was 5.7 ± 1.8 days. All patients were discharged home after rehabilitation. There were no cases of COVID-19 infection among healthcare workers during the study period., Conclusion: These strategies allowed us to maintain a service for urgent and emergency procedures and may prove useful for larger countries when there is decrease in COVID-19 cases and planning for the restart of elective cardiac surgery., (© 2020 The Authors. Journal of Cardiac Surgery published by Wiley Periodicals LLC.)

Real-time decision making needs evaluating quantities of interest (QoI) in almost real time. When these QoI are related to models based on physics, the use of Model Order Reduction techniques allows speeding-up calculations, enabling fast and accurate evaluations. To accommodate real-time constraints, a valuable route consists of computing parametric solutions-the so-called computational vademecums-that constructed off-line, can be inspected on-line. However, when dealing with shapes and topologies (complex or rich microstructures) their parametric description constitutes a major difficulty. In this paper, we propose using Topological Data Analysis for describing those rich topologies and morphologies in a concise way, and then using the associated topological descriptions for generating accurate supervised classification and nonlinear regression, enabling an almost real-time evaluation of QoI and the associated decision making.

Structural changes to the wall of the left atrium are known to occur with conditions that predispose to Atrial fibrillation. Imaging studies have demonstrated that these changes may be detected non-invasively. An important indicator of this structural change is the wall's thickness. Present studies have commonly measured the wall thickness at few discrete locations. Dense measurements with computer algorithms may be possible on cardiac scans of Computed Tomography (CT) and Magnetic Resonance Imaging (MRI). The task is challenging as the atrial wall is a thin tissue and the imaging resolution is a limiting factor. It is unclear how accurate algorithms may get and how they compare in this new emerging area. We approached this problem of comparability with the Segmentation of Left Atrial Wall for Thickness (SLAWT) challenge organised in conjunction with MICCAI 2016 conference. This manuscript presents the algorithms that had participated and evaluation strategies for comparing them on the challenge image database that is now open-source. The image database consisted of cardiac CT (n=10) and MRI (n=10) of healthy and diseased subjects. A total of 6 algorithms were evaluated with different metrics, with 3 algorithms in each modality. Segmentation of the wall with algorithms was found to be feasible in both modalities. There was generally a lack of accuracy in the algorithms and inter-rater differences showed that algorithms could do better. Benchmarks were determined and algorithms were ranked to allow future algorithms to be ranked alongside the state-of-the-art techniques presented in this work. A mean atlas was also constructed from both modalities to illustrate the variation in thickness within this small cohort., (Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.)

The elaboration of biomimetic materials inspired from the specific structure of native bone is one the main goal of tissue engineering approaches. To offer the most appropriate environment for bone reconstruction, we combined electrospinning and electrospraying to elaborate an innovative scaffold composed of alternating layers of polycaprolactone (PCL) and hydroxyapatite (HA). In our approach, the electrospun PCL was shaped into a honeycomb-like structure with an inner diameter of 160 μm, capable of providing bone cells with a 3D environment while ensuring the material biomechanical strength. After 5 days of culture without any differentiation factor, the murine embryonic cell line demonstrated excellent cell viability on contact with the PCL-HA structures as well as active colonization of the scaffold. The cell differentiation, as tested by RT-qPCR, revealed a 6-fold increase in the expression of the RNA of the Bglap involved in bone mineralization as compared to a classical 2D culture. This differentiation of the cells into osteoblasts was confirmed by alkaline phosphatase staining of the scaffold cultivated with the cell lineage. Later on, organotypic cultures of embryonic bone tissues showed the high capacity of the PCL-HA honeycomb structure to guide the migration of differentiated bone cells throughout the cavities and the ridge of the biomaterial, with a colonization surface twice as big as that of the control. Taken together, our results indicate that PCL-HA honeycomb structures are biomimetic supports that promotes in vitro osteocompatibility, osteoconduction, and osteoinduction and could be suitable for being used for bone reconstruction in complex situations such as the repair of maxillofacial defects.

Interpenetrating polymer networks (IPNs) have gained great attention for a number of biomedical applications due to their improved properties compared to individual components alone. In this study, we investigated the capacity of newly-developed naturally-derived IPNs as potential biomaterials for tissue engineering. These IPNs combine the biologic properties of a fibrous fibrin network polymerized at the nanoscale and the mechanical stability of polyethylene oxide (PEO). First, we assessed their cytotoxicity in vitro on L929 fibroblasts. We further evaluated their biocompatibility ex vivo with a chick embryo organotypic culture model. Subcutaneous implantations of the matrices were subsequently conducted on nude mice to investigate their biocompatibility in vivo. Our preliminary data highlighted that our biomaterials were non-cytotoxic (viability above 90%). The organotypic culture showed that the IPN matrices induced higher cell adhesion (across all the explanted organ tissues) and migration (skin, intestine) than the control groups, suggesting the advantages of using a biomimetic, yet mechanically-reinforced IPN-based matrix. We observed no major inflammatory response up to 12 weeks post implantation. All together, these data suggest that these fibrin-based IPNs are promising biomaterials for tissue engineering., Competing Interests: The authors declare no conflict of interest.

Glass sheets covered with aligned electrospun silk fibroin (Bombyx mori) were compared to tissue culture-treated Thermanox® coverslips, using an organotypic culture method. Different chick embryo organ behaviours were analysed in terms of circularity, cell growth and cell adhesion after being cultivated in contact with these two materials. The circularity (cell layer shape corresponding to the trend of the biomaterials to induce a specific directionality) depends on the organ used when in contact with silk fibroin. This biomaterial induced higher cell adhesion (kidney) or lower cell adhesion (spine) compared to Thermanox. Cell growth, represented by the cell layer area (mm 2 ), was also drastically reduced (gonad) or increased (blood vessel) on the silk fibroin. Organotypic culture is a rapid, cost effective and relatively simple method to evaluate different parameters, allowing prescreening of morphology and cytocompatibility to select the appropriate applications for new biomaterials. In the present study we compared the morphology of different organotypic cultures on orientated silk and Thermanox as growth supports to rapidly evaluate the benefit of a silk-based biomaterial for tissue engineering. Copyright © 2014 John Wiley & Sons, Ltd., (Copyright © 2014 John Wiley & Sons, Ltd.)

Thin-Film-Transistors Liquid-Crystal Display has become a standard in the field of displays. However, the structure of these devices presents interest not only in that field, but also for biomedical applications. One of the key components, called here TFT substrate, is a glass substrate with a dense and large array of thousands of transparent micro-electrodes that can be considered as a large scale multi-electrode array(s). Multi-electrode array(s) are widely used for in vitro electrical investigations on neurons and brain, allowing excitation, registration, and recording of their activity. However, the range of application of conventional multi-electrode array(s) is usually limited to some tens of cells in a homogeneous cell culture, because of a small area, small number and a low density of the micro-electrodes. TFT substrates do not have these limitations and the authors are currently studying the possibility to use TFT substrates as new tools for in vitro electrical investigation on tissues and organoids. In this respect, experiments to determine the cyto-biocompatibility of TFT substrates with tissues were conducted and are presented in this study. The investigation was performed using an organotypic culture method with explants of brain and liver tissues of chick embryos. The results in term of morphology, cell migration, cell density and adhesion were compared with the results from Thermanox ® , a conventional plastic for cell culture, and with polydimethylsiloxane, a hydrophobic silicone. The results with TFT substrates showed similar results as for the Thermanox ® , despite the TFT hydrophobicity. TFT substrates have a weak cell adhesion and promote cell migration similarly to Thermanox ® . It could be concluded that the TFT substrates are cyto-biocompatible with the two studied organs.

Purpose: The increasing demand for esthetically pleasing results has contributed to the use of ceramics for dental implant abutments. The aim of this study was to compare the biological response of epithelial tissue cultivated on lithium disilicate (LS 2 ) and zirconium oxide (ZrO 2 ) ceramics. Understanding the relevant physicochemical and mechanical properties of these ceramics will help identify the optimal material for facilitating gingival wound closure., Methods: Both biomaterials were prepared with 2 different surface treatments: raw and polished. Their physicochemical characteristics were analyzed by contact angle measurements, scanning white-light interferometry, and scanning electron microscopy. An organotypic culture was then performed using a chicken epithelium model to simulate peri-implant soft tissue. We measured the contact angle, hydrophobicity, and roughness of the materials as well as the tissue behavior at their surfaces (cell migration and cell adhesion)., Results: The best cell migration was observed on ZrO 2 ceramic. Cell adhesion was also drastically lower on the polished ZrO 2 ceramic than on both the raw and polished LS 2 . Evaluating various surface topographies of LS 2 showed that increasing surface roughness improved cell adhesion, leading to an increase of up to 13%., Conclusions: Our results demonstrate that a biomaterial, here LS 2 , can be modified using simple surface changes in order to finely modulate soft tissue adhesion. Strong adhesion at the abutment associated with weak migration assists in gingival wound healing. On the same material, polishing can reduce cell adhesion without drastically modifying cell migration. A comparison of LS 2 and ZrO 2 ceramic showed that LS 2 was more conducive to creating varying tissue reactions. Our results can help dental surgeons to choose, especially for esthetic implant abutments, the most appropriate biomaterial as well as the most appropriate surface treatment to use in accordance with specific clinical dental applications., Competing Interests: No potential conflict of interest relevant to this article was reported.

In this work, we have investigated the potential of perfluoropolyether (PFPE) polymers for use in biomaterial applications, especially in cell culture and tissue engineering. PFPE substrates were synthesized by the photocuring of liquid PFPE urethane dimethacrylate. These surfaces were then modified by ECM protein coatings and microstructuration, to promote cell adhesion and migration. The surface properties of PFPE and PDMS (used as a reference) samples were studied by static contact angle measurements and AFM imaging. Both polymer surfaces were hydrophobic, having sessile air-water contact angles superior to 100°. Collagen and fibronectin coatings were found to change the wettability of PFPE and PDMS samples. The biological testing of substrates was done using a liver organotypic culture to evaluate the migration and density of liver cells. The results over seven days of culture demonstrated that the migration and density of cells cultured under untreated PFPE were higher than the migration and density of cells cultured under PDMS. ECM protein coatings enhanced cell migration from liver explants cultured on PFPE or PDMS. Furthermore, these coatings were more efficient in the case of a PFPE sample. From a second series of tests, in which the PFPE was microstructured, it was found that microstructures promoted the formation of a 3D cell layer. These results indicate that PFPE polymers have a potential for use in the development of biomaterials for tissue engineering and cell culture., (Copyright © 2016 Elsevier B.V. All rights reserved.)