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Pelvic organ prolapse (POP) is a gynecological disorder described by the descent of superior pelvic organs into or out of the vagina as a consequence of disrupted muscles and tissue. A thorough understanding of the etiology of POP is limited by the availability of clinically relevant samples, restricting longitudinal POP studies on soft-tissue biomechanics and structure to POP-induced models such as fibulin-5 knockout (FBLN5^-/-) mice. Despite being a principal constituent in the extracellular matrix, little is known about structural perturbations to collagen networks in theFBLN5^-/-mouse cervix. We identify significantly different collagen network populations in normal and prolapsed cervical cross-sections using two label-free, nonlinear microscopy techniques. Collagen in the prolapsed mouse cervix tends to be more isotropic, and displays reduced alignment persistence via 2-D Fourier transform analysis of images acquired using second harmonic generation microscopy. Furthermore, coherent Raman hyperspectral imaging revealed elevated disorder in the secondary structure of collagen in prolapsed tissues. Our results underscore the need forin situmultimodal monitoring of collagen organization to improve POP predictive capabilities. 

Abstract Thromboembolic diseases are a significant cause of mortality and are clinically treated enzymatically with tissue plasminogen activator (tPA). Interestingly, prior studies in fibrin fibers and fibrin gels have demonstrated that thrombolysis may be mechanically sensitive. This study aims to expand mechano‐lytic studies to whole blood clots. Furthermore, this study investigates not only how mechanics impacts lysis but also how lysis impacts mechanics. Therefore, clots made from whole human blood are exposed to tPA while the clots are either stretched or unstretched. After, the resulting degree of clot lysis is measured by weighing the clots and by measuring the concentration of D‐dimer in the surrounding bath. Additionally, each clot's mechanical properties are measured. This study finds that mechanical stretch accelerates loss in clot weight but does not impact the lysis rate as measured by D‐dimer. Moreover, lysis not only removes clot volume but also reduces the remaining clot's stiffness and toughness. In summary, tPA‐induced lysis of whole clot appears mechanically insensitive, but stretch reduces clot weight. Furthermore, results show that thrombolysis weakens clot. This suggests that thrombolysis may increase the risk of secondary embolizations but may also ease clot removal during thrombectomy, for example.