Can a foreign body migrate against natural body barriers?

Pericardial foreign bodies (FBs) are a rare cause of chest pain in children. They can reach the pericardium through several routes including direct or iatrogenic implantation, transbronchial or transesophageal migration of inhaled or swallowed FBs. We reported a case of a 4-year-old girl presenting with persistent chest pain for 1 month. The child described the pain as ‘stitching’ in nature localized on the left side of the sternum. The child presented with increased pain intensity and a new onset of fever and cough. No history of chocking or swallowing of FB and no signs of trauma or child abuse were noted. Chest radiography revealed a needle in the left side of the chest. Computed tomography scan and echocardiography were used to precisely localize the needle and exclude intracardiac extension. ECG showed elevated ST segment and cardiac enzymes were normal. Removal of the needle was carried out surgically under fluoroscopic guidance. A small portion of the needle was found intrapericardially complicated by localized purulent pericarditis. The child had uneventful recovery and was discharged from the hospital on postoperative day 3.Keywords: foreign bodies, pain, pediatrics, pericardium, thoracic surger

Baseline Hemodynamics Including Aortic and Pulmonary Blood Flow in a Chronic Bovine Model

The use of large animal models in the preclinical setting has expanded and become increasingly valuable for evaluating the safety and efficacy of new therapies and devices. Here, we report normal hemodynamic values, including aortic and pulmonary blood flow, in a bovine model at rest and during exercise after a control procedure. We performed a left lateral thoracotomy and implanted fluid-filled pressure lines (aortic pressure, right atrial pressure, left atrial pressure, pulmonary artery pressure) and left (systemic) and right (pulmonary) flow probe lines. Throughout the postoperative period, the calf’s physiologic pressures, vital signs, aortic and pulmonary blood flow, and pulmonary and systemic vascular resistance were recorded hourly at rest and during treadmill exercise evaluations. When pressures and flow rates at baseline and during treadmill trials were compared, we observed a physiologic response to exercise similar to that seen in humans, with a sympathetic discharge that increased systolic blood pressure. However, the rise in mean arterial pressure was much lower due to an overall decrease in vascular resistance, which increased blood flow. This study provides investigators, device engineers, and manufacturers with normal bovine cardiovascular physiology data that can be used for technical consideration during device development for preclinical trials

Baseline Hemodynamics Including Aortic and Pulmonary Blood Flow in a Chronic Bovine Model

The use of large animal models in the preclinical setting has expanded and become increasingly valuable for evaluating the safety and efficacy of new therapies and devices. Here, we report normal hemodynamic values, including aortic and pulmonary blood flow, in a bovine model at rest and during exercise after a control procedure. We performed a left lateral thoracotomy and implanted fluid-filled pressure lines (aortic pressure, right atrial pressure, left atrial pressure, pulmonary artery pressure) and left (systemic) and right (pulmonary) flow probe lines. Throughout the postoperative period, the calf’s physiologic pressures, vital signs, aortic and pulmonary blood flow, and pulmonary and systemic vascular resistance were recorded hourly at rest and during treadmill exercise evaluations. When pressures and flow rates at baseline and during treadmill trials were compared, we observed a physiologic response to exercise similar to that seen in humans, with a sympathetic discharge that increased systolic blood pressure. However, the rise in mean arterial pressure was much lower due to an overall decrease in vascular resistance, which increased blood flow. This study provides investigators, device engineers, and manufacturers with normal bovine cardiovascular physiology data that can be used for technical consideration during device development for preclinical trials

Use of Ethanol Injections to Create a Complete Atrioventricular Block in a Rat Model

Complete atrioventricular block (AVB) is an abnormal heart rhythm resulting from a defect in the cardiac conduction system. Patients with complete AVB are at risk of symptoms ranging from syncope or hypotension to cardiovascular collapse or sudden cardiac death. A reliable animal model of complete AVB is essential for understanding the mechanisms underlying the fatal hemodynamic effects and alterations in electrical conductivity associated with this arrhythmia. We evaluated the use of ethanol injections in a systematic surgical approach to create a complete AVB model in rats. We used eight Sprague Dawley rats (8 weeks old, 220 ± 30 g): four received a 70% ethanol injection in the AV node, and four received a similar injection of 0.9% sodium chloride. Our surgical approach involved performing a partial sternotomy, using the epicardial fat as a landmark for ethanol injections. Animals were followed for 7 and 14 days. Complete AVB was successfully induced in all four rats that received ethanol injections. Rats in the control group experienced a transient AVB with a return to sinus rhythm. Our study found that using 70% ethanol injections in a systematic surgical approach is a reliable, safe, and reproducible way of creating a complete AVB model in rats

An epicardial bioelectronic patch made from soft rubbery materials and capable of spatiotemporal mapping of electrophysiological activity

An epicardial bioelectronic patch is an important device for investigating and treating heart diseases. The ideal device should possess cardiac-tissue-like mechanical softness and deformability, and be able to perform spatiotemporal mapping of cardiac conduction characteristics and other physical parameters. However, existing patches constructed from rigid materials with structurally engineered mechanical stretchability still have a hard-soft interface with the epicardium, which can strain cardiac tissue and does not allow for deformation with a beating heart. Alternatively, patches made from intrinsically soft materials lack spatiotemporal mapping or sensing capabilities. Here, we report an epicardial bioelectronic patch that is made from materials matching the mechanical softness of heart tissue and can perform spatiotemporal mapping of electrophysiological activity, as well as strain and temperature sensing. Its capabilities are illustrated on a beating porcine heart. We also show that the patch can provide therapeutic capabilities (electrical pacing and thermal ablation), and that a rubbery mechanoelectrical transducer can harvest energy from heart beats, potentially providing a power source for epicardial devices. An epicardial patch made from materials that match the mechanical softness of heart tissue can perform spatiotemporal mapping of electrophysiological activity, as well as strain and temperature sensing, pacing and ablation therapies, and energy harvesting, while deforming with a beating heart

Correction: Regeneration of esophagus using a scaffold-free biomimetic structure created with bio-three-dimensional printing.

[This corrects the article DOI: 10.1371/journal.pone.0211339.]

Regeneration of esophagus using a scaffold-free biomimetic structure created with bio-three-dimensional printing

Various strategies have been attempted to replace esophageal defects with natural or artificial substitutes using tissue engineering. However, these methods have not yet reached clinical application because of the high risks related to their immunogenicity or insufficient biocompatibility. In this study, we developed a scaffold-free structure with a mixture of cell types using bio-three-dimensional (3D) printing technology and assessed its characteristics in vitro and in vivo after transplantation into rats. Normal human dermal fibroblasts, human esophageal smooth muscle cells, human bone marrow-derived mesenchymal stem cells, and human umbilical vein endothelial cells were purchased and used as a cell source. After the preparation of multicellular spheroids, esophageal-like tube structures were prepared by bio-3D printing. The structures were matured in a bioreactor and transplanted into 10-12- week-old F344 male rats as esophageal grafts under general anesthesia. Mechanical and histochemical assessment of the structures were performed. Among 4 types of structures evaluated, those with the larger proportion of mesenchymal stem cells tended to show greater strength and expansion on mechanical testing and highly expressed α-smooth muscle actin and vascular endothelial growth factor on immunohistochemistry. Therefore, the structure with the larger proportion of mesenchymal stem cells was selected for transplantation. The scaffold-free structures had sufficient strength for transplantation between the esophagus and stomach using silicon stents.The structures were maintained in vivo for 30 days after transplantation. Smooth muscle cells were maintained, and flat epithelium extended and covered the inner surface of the lumen. Food had also passed through the structure. These results suggested that the esophagus-like scaffold-free tubular structures created using bio-3D printing could hold promise as a substitute for the repair of esophageal defects

Drawn‐on‐Skin Sensors from Fully Biocompatible Inks toward High‐Quality Electrophysiology

The need to develop wearable devices for personal health monitoring, diagnostics, and therapy has inspired the production of innovative on-demand, customizable technologies. Several of these technologies enable printing of raw electronic materials directly onto biological organs and tissues. However, few of them have been thoroughly investigated for biocompatibility of the raw materials on the cellular, tissue, and organ levels or with different cell types. In addition, highly accurate multiday in vivo monitoring using such on-demand, in situ fabricated devices has yet to be done. Presented herein is the first fully biocompatible, on-skin fabricated electronics for multiple cell types and tissues that can capture electrophysiological signals with high fidelity. While also demonstrating improved mechanical and electrical properties, the drawn-on-skin ink retains its properties under various writing conditions, which minimizes the variation in electrical performance. Furthermore, the drawn-on-skin ink shows excellent biocompatibility with cardiomyocytes, neurons, mice skin tissue, and human skin. The high signal-to-noise ratios of the electrophysiological signals recorded with the DoS sensor over multiple days demonstrate its potential for personalized, long-term, and accurate electrophysiological health monitoring