A Challenging Case of Stent Dislodgement During Percutaneous Coronary Intervention Complicated by Peripheral Embolization.

We report a challenging case of stent dislodgement for a 49-year-old male with a history of end-stage renal disease and insulin-dependent diabetes undergoing an elective coronary angiogram for cardiac risk stratification before kidney transplant surgery. A diagnostic transradial coronary angiogram was performed showing two severe type A lesions to the proximal and distal left circumflex artery (LCx). While attempting to stent the proximal LCx, the stent dislodged to the left main coronary artery (LMCA). The stent was successfully retrieved from the LMCA via the transradial route using the small balloon anchoring technique. Unfortunately, while attempting to retrieve the stent-balloon assembly, the stent was accidentally stripped off the balloon embolizing to the right superior gluteal artery. Given the stable location, no attempt was made to retrieve the stent and the patient had no complications on follow-up. This case highlights the challenges in managing coronary stent loss including risk factors for stent dislodgement, methods to retrieve the stent, and the risk of stent embolization.

Identifying the effectiveness of 3D culture systems to recapitulate breast tumor tissue in situ.

PURPOSE: Breast cancer heterogeneity contributes to chemotherapy resistance and decreased patient survival. To improve patient outcomes it is essential to develop a technology that is able to rapidly select the most efficacious therapy that targets the diverse phenotypes present within the tumor. Breast cancer organoid technologies are proposed as an attractive approach for evaluating drug responses prior to patient therapy. However, there remain challenges in evaluating the effectiveness of organoid cultures to recapitulate the heterogeneity present in the patient tumor in situ. METHOD: Organoids were generated from seven normal breast and nineteen breast cancer tissues diagnosed as estrogen receptor positive or triple negative. The Jensen-Shannon divergence index, a measure of the similarity between distributions, was used to compare and evaluate heterogeneity in starting tissue and their resultant organoids. Heterogeneity was analyzed using cytokeratin 8 and cytokeratin 14, which provided an easily scored readout. RESULTS: In the in vitro culture system HER1 and FGFR were able to drive intra-tumor heterogeneity to generate divergent phenotypes that have different sensitivities to chemotherapies. CONCLUSION: Our methodology, which focuses on quantifiable cellular phenotypes, provides a tractable system that complements omics approaches to provide an unprecedented view of heterogeneity and will enhance the identification of novel therapies and facilitate personalized medicine.

Revelations from the Clinic: Protective Behaviors and Perceptions among People at High Risk for Severe Illness from COVID-19.

OBJECTIVES: The CDC has warned of increased risk for severe COVID-19 illness among those with certain preexisting conditions. Protective behaviors such as social distancing and mask-wearing have been shown effective at curbing infection rates. These practices are subject to individual perceptions of risk and responsibility. This study aimed to characterize the risk perceptions and protective behaviors of residents in a rural central Michigan region. Specifically, we examined whether individual risk status predicted protective behaviors and concern about the pandemic. METHODS: Participants were identified via medical records at participating clinics. The high-risk group was those with conditions that put them at increased risk of severe illness from COVID-19, and was compared to healthy controls. Data were collected via phone survey. Participants were asked about their protective behaviors and level of concern about the ongoing pandemic. RESULTS: A total of 150 patients participated in the survey; 73 were high-risk acknowledgers, 29 were high-risk deniers, and 48 were healthy controls. There was no significant difference between the groups on level of concern regarding the pandemic or protective behaviors (P > .05). Compared to other comorbidities, obese people were significantly more likely to deny their risk (P < .05). CONCLUSIONS: In this study, high risk, whether acknowledged or denied, did not appear to significantly impact behaviors or concern. The high percentage of those at high risk who did not acknowledge this suggests many factors including a potential lack of patient education regarding their comorbidities, specifically, how their illness increases their risk of severe illness from COVID-19.

Accounting for tumor heterogeneity when using CRISPR-Cas9 for cancer progression and drug sensitivity studies.

Gene editing protocols often require the use of a subcloning step to isolate successfully edited cells, the behavior of which is then compared to the aggregate parental population and/or other non-edited subclones. Here we demonstrate that the inherent functional heterogeneity present in many cell lines can render these populations inappropriate controls, resulting in erroneous interpretations of experimental findings. We describe a novel CRISPR/Cas9 protocol that incorporates a single-cell cloning step prior to gene editing, allowing for the generation of appropriately matched, functionally equivalent control and edited cell lines. As a proof of concept, we generated matched control and osteopontin-knockout Her2+ and Estrogen receptor-negative murine mammary carcinoma cell lines and demonstrated that the osteopontin-knockout cell lines exhibit the expected biological phenotypes, including unaffected primary tumor growth kinetics and reduced metastatic outgrowth in female FVB mice. Using these matched cell lines, we discovered that osteopontin-knockout mammary tumors were more sensitive than control tumors to chemotherapy in vivo. Our results demonstrate that heterogeneity must be considered during experimental design when utilizing gene editing protocols and provide a solution to account for it.