<p dir="ltr">Murine, or small rodent, models can provide valuable and translatable insights into human pathophysiology. Specifically, we are looking to combine murine models and high-frequency ultrasound to non-invasively investigate microrobot drug delivery systems, cardiac effects of lactation on the mother during postpartum, and cardiac remodeling due to the combination of pregnancy and hypertension.</p><p dir="ltr">Currently, we are looking at the applications of microrobots within the colon to provide targeted treatment for patients suffering from inflammatory bowel disease (IBD). IBD is an overarching term encompassing chronic inflammation of the digestive tract tissue. The standard treatment of IBD includes oral and injectable treatments depending on disease severity. The drawbacks of these therapeutics are the associated systemic toxicity, non-specific treatment allocation, and degradation of the treatment in proximal portions of the gastrointestinal (GI) system. The goal of this research is to use an external magnetic torque to cause the microrobots to tumble to targeted areas of inflammation and release a drug payload. Retroactive locomotion of these microrobots can avoid degradation in the proximal GI tract. Therefore, these microrobots need a smaller drug payload to provide the same efficacy as traditional treatments.</p><p dir="ltr">The cardiovascular system adapts to meet the growing physiological demands of pregnancy. Although this change has been greatly studied, it is unclear if this change in shape and function returns to prepregnant values during postpartum. Previous research has also shown that lactation affects the mother’s hemodynamics during postpartum, but its impact on cardiac morphology is still not completely understood. To study this further, we longitudinally tracked cardiovascular changes using ultrasound and blood pressure measurements in C57BL6/J mice during pregnancy and postpartum that were either lactating or not.</p><p dir="ltr">Chronic hypertension affects approximately 1 in 20 pregnancies and its prevalence in pregnancies continues to increase. The maternal cardiovascular system goes through dynamic changes during pregnancy to meet the demands of perfusing the gestation, especially during the exponential growth seen later in pregnancy. Studies with female C57BL6/J mice demonstrate comparable cardiovascular changes during pregnancy to those observed in humans. Additionally, a study using rats showed the cardioprotective properties of pregnancy against angiotensin II-induced fibrosis. The objective of this study is to characterize non-invasive cardiac remodeling in a small animal model of hypertensive disorders in pregnancy. We used a combination of ultrasound imaging and noninvasive blood pressure measurements to longitudinally monitor the physiological adaptations that occur during pregnancy with superimposed hypertension.</p>

<p>Radiation-induced lung injury (RILI) is a common condition in the setting of lung and breast cancer. Often, patients who suffer from RILI experience pneumonitis and pulmonary fibrosis months after treatment. These pathologies have commonly been modeled using mice and observing their deterioration until mortality and quantifying pathology on histological sections.<b> </b></p> <p>With this study, we used a longitudinal microCT and a 7T MRI to characterize male C57Bl/6 mice irradiated with a single dose of 20 Gy to the whole thoracic area delivered by an X-Rad cabinent irradiator. CT was performed with a respiratory gating sequence at 2 week timepoints to construct an RIPF model. The fraction of RIPF to total lung volume was calculated at each time point from images, and the data was anaylzed using one-way ANOVA Welch and Dunnett’s T3 multiple comparisons tests. Tidal lung volumes were also calculated and anlyazed in a simlar manner. Mice were then imaged using MRI and CT at 0, 5, and 8 week timepoints to compare results. These results were analyzed for comparison (ANOVA and Dunnett’s T3) and correlation (Pearson’s r) with each other. Histology was later performed using H&E and Trichrome stains to provide ex-vivo verification of pathology.<b> </b>At the 10-12 week time point ( ) significant RIPF formed. Weeks proceeding showed increased significance until the 22+ week timepoint, which showed less statistical significance ( ) due to increased variance at this timepoint. Dunnett’s T3 test showed no significant differences between tidal lung volumes over time. Tests also showed no significant differences between CT and MRI results with a correlation coefficient of .<b> </b>Early in the study, problems arose when pre-marture mortality was occurring to a significant portion of our subjects. Analysis later showed issues during irradiation that resulted in significant dose being absorbed by the stomach. Adjusting our shiedling lead to increased early survival of our subjects enabling us to contine our study. Significant RIPF development was not significant until 10-12 weeks post-irradiation, then RIPF became more severe at proceeding timepoints. Tidal lung volume showed no significant deviation over the development of RIPF. This result is most likely affected by the variation of results at later timepoints, since several mice with severe RIPF were significantly hindered in their ability to breathe during the study. MRI results showed close correlation with CT results and prodcued similar values at early timepoints. However, noticeable differences were seen at later timepoints when significant RIPF developed ( ). <b></b></p>