Leafy greens contaminated with Shiga toxin-producing Escherichia coli (STEC) have continued to cause foodborne illness outbreaks in recent years and present a threat to public health. An important component of foodborne illness outbreak investigations is determining the source of the outbreak vehicle through traceback investigations. The Food and Drug Administration is home to traceback investigation experts that employ a standardized process to initiate, execute, and interpret the results of traceback investigations in collaboration with the Centers for Disease Control and Prevention and state and local partners. Traceback investigations of three outbreaks of STEC infections linked to romaine lettuce in 2018 and 2019 were examined to demonstrate challenges, limitations, and opportunities for improvement. The three outbreaks resulted in a total of 474 illnesses, 215 hospitalizations, and five deaths. These illnesses were linked to the consumption of romaine lettuce from three distinct growing regions in Arizona and California. Some of the challenges encountered included the time it took to initiate a traceback, limited product-identifying information throughout the supply chain, lack of interoperability in record keeping systems, and co-mingling of product from multiple suppliers. These challenges led to time delays in the identification of the farm source of the leafy greens and the inability to identify the root cause of contamination. Implementation of technology enabled traceability systems, testing of these systems, and future regulations to incentivize adoption of traceability systems are some of the initiatives that will help address these challenges by improving traceback investigations and ultimately preventing foodborne illnesses and future outbreaks from occurring. Matrix Metalloproteinases (MMPs) play an important role in extracellular matrix regulation during cell growth and wound healing. Increased expression of MMP-12 (human macrophage elastase) has been reported in inflammatory bowel disease (IBD) which is characterized by the loss of epithelial tight junction (TJ) barrier function and an excessive inflammatory response. The aim of this study was to investigate the role of MMP-12 in intestinal TJ barrier function and inflammation. Wild type (WT) and MMP-12 -/- mice were subjected to experimental acute or chronic dextran sodium sulfate (DSS) colitis. The mouse colonic permeability was measured in vivo by recycling perfusion of the entire colon and ex vivo by Ussing chamber studies. DSS administration increased colonic permeability through modulation of TJ proteins and also increased MMP-12 expression in the colonic mucosa of WT mice. The acute as well as chronic DSS-induced increase in colonic TJ permeability and the severity of DSS colitis was found to be marced macrophage infiltration and transmigration, and reduced basement membrane laminin degradation. Further in vitro and in vivo studies show that macrophage transmigration across epithelial layer is MMP-12 dependent and the epithelial TJ barrier is compromised during macrophage transmigration. Together, this data demonstrates that MMP-12-mediated degradation of basement membrane laminin, macrophage transmigration, and associated loss of intestinal TJ barrier are key pathogenic factors for intestinal inflammation. Giant cell arteritis (GCA) is a large vessel vasculitis for which triggering factors remain unknown. Clonal hematopoiesis (CH) was associated with atherosclerosis through the induction of inflammation in myeloid cells, and data suggest that CH expansion and inflammation may support each other to induce a proinflammatory loop. Our objective was to describe the impact of JAK2p.V617F-mutated myeloproliferative neoplasms (MPN) on GCA and to screen MPN-free patients for CH mutations. We performed a retrospective case-control study comparing characteristics of 21 GCA patients with MPN and 42 age and gender-matched GCA patients without MPN. Also, 18 GCA patients were screened for CH through Next Generation Sequencing. The most frequent associated MPN was essential thrombocythemia (ET) (n = 11). Compared to controls, GCA patients with MPN had less frequent cephalic symptoms (71.4 vs. 97.6%, p = 0.004) and higher platelets count at baseline [485 (346-586) vs. 346 [IQR 296-418] x 109/L, p = 0.02). There was no difference between groups for other clinical features. Overall survival was significantly shorter in patients with MPN compared to controls [HR 8.2 (95% CI 1.2-56.6), p = 0.03]. Finally, screening for CH using NGS in 15 GCA patients without MPN revealed CH in 33%. GCA patients with MPN display higher platelets count and shorter overall survival than controls. This association could not be fortuitous given the possible pathophysiological relationship between the two diseases. CH was found in one third of GCA patients, which may be higher than the expected prevalence for similar age, what should be confirmed in a larger cohort. GCA patients with MPN display higher platelets count and shorter overall survival than controls. This association could not be fortuitous given the possible pathophysiological relationship between the two diseases. CH was found in one third of GCA patients, which may be higher than the expected prevalence for similar age, what should be confirmed in a larger cohort. Pathology on-call experiences help prepare trainees for successful transition from residency to independent practice, and as such are an integral component of training. https://www.selleckchem.com/products/amg510.html However, few data exist on anatomic pathology resident on-call workload and experience. To obtain an overall picture of the anatomic pathology on-call experience to inform and improve resident education. Retrospective and prospective review of the daily anatomic pathology on-call summaries from July 2016 to June 2020. During the first 2 years of the study (ie, retrospective portion), only 19% of on-call summaries (138 of 730) were available for review. After interventions, the on-call summary submission rate jumped to 98% (716 of 731). After-hours calls were most frequent on weekdays from 5 to 8 pm. The most frequent requests were for frozen sections (55%; 619 of 1125 calls), inquiries regarding disposition of fresh placentas (13%; 148 of 1125 calls), and inquiries regarding disposition of various other specimens (6%; 68 of 1125 calls).