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Due to the unique physicochemical properties exhibited by materials with nanoscale dimensions, there is currently a continuous increase in the number of engineered nanomaterials (ENMs) used in consumer goods. However, several reports associate ENM exposure to negative health outcomes such as cardiovascular diseases. Therefore, understanding the pathological consequences of ENM exposure represents an important challenge, requiring model systems that can provide mechanistic insights across different levels of ENM-based toxicity. To achieve this, we developed a mussel-inspired 3D microphysiological system (MPS) to measure cardiac contractility in the presence of ENMs. While multiple cardiac MPS have been reported as alternatives to in vivo testing, most systems only partially recapitulate the native extracellular matrix (ECM) structure. Here, we show how adhesive and aligned polydopamine (PDA)/polycaprolactone (PCL) nanofiber can be used to emulate the 3D native ECM environment of the myocardium. Such nanofiber scaffolds can support the formation of anisotropic and contractile muscular tissues. By integrating these fibers in a cardiac MPS, we assessed the effects of TiO2 and Ag nanoparticles on the contractile function of cardiac tissues. We found that these ENMs decrease the contractile function of cardiac tissues through structural damage to tissue architecture. Furthermore, the MPS with embedded sensors herein presents a way to non-invasively monitor the effects of ENM on cardiac tissue contractility at different time points. These results demonstrate the utility of our MPS as an analytical platform for understanding the functional impacts of ENMs while providing a biomimetic microenvironment to in vitro cardiac tissue samples. [Figure not available: see fulltext.]

John Zimmerman, one of former superior general William Slattery’s assistants, recalls important events of Slattery’s generalate: the canonization of Catherine Laboure, the Bossarelli affair, the formulation of the revised Constitutions of 1953, the constitution of two canonical provinces in France, the General Curia’s move to Rome, the tercentenary celebrations of the deaths of Vincent DePaul and Louise de Marillac, Slattery’s attendance of the Second Vatican Council, Elizabeth Seton’s beatification, and general assemblies, including the Extraordinary General Assembly of 1968–1969. The article includes Slattery’s acceptance and resignation speeches regarding his office, as well as his proposal of his resignation. James Richardson’s speeches about his election as superior general are also given.