Evaluating learning curves and competence in colorectal EMR among advanced endoscopy fellows: a pilot multicenter prospective trial using cumulative sum analysis.

BACKGROUND AND AIMS: Data on colorectal EMR (C-EMR) training are lacking. We aimed to evaluate C-EMR training among advanced endoscopy fellows (AEFs) by using a standardized assessment tool (STAT). METHODS: This multicenter prospective study used a STAT to grade AEF training in C-EMR during their 12-month fellowship. Cumulative sum analysis was used to establish learning curves and competence for cognitive and technical components of C-EMR and overall performance. Sensitivity analysis was performed by varying failure rates. AEFs completed a self-assessment questionnaire to assess their comfort level with performing C-EMR at the completion of their fellowship. RESULTS: Six AEFs (189 C-EMRs; mean per AEF, 31.5 ± 18.5) were included. Mean polyp size was 24.3 ± 12.6 mm, and mean procedure time was 22.6 ± 16.1 minutes. Learning curve analyses revealed that less than 50% of AEFs achieved competence for key cognitive and technical C-EMR endpoints. All 6 AEFs reported feeling comfortable performing C-EMR independently at the end of their training, although only 2 of them achieved competence in their overall performance. The minimum threshold to achieve competence in these 2 AEFs was 25 C-EMRs. CONCLUSIONS: A relatively low proportion of AEFs achieved competence on key cognitive and technical aspects of C-EMR during their 12-month fellowship. The relatively low number of C-EMRs performed by AEFs may be insufficient to achieve competence, in spite of their self-reported readiness for independent practice. These pilot data serve as an initial framework for competence threshold, and suggest the need for validated tools for formal C-EMR training assessment.

Combinatorial drug discovery in nanoliter droplets.

Combinatorial drug treatment strategies perturb biological networks synergistically to achieve therapeutic effects and represent major opportunities to develop advanced treatments across a variety of human disease areas. However, the discovery of new combinatorial treatments is challenged by the sheer scale of combinatorial chemical space. Here, we report a high-throughput system for nanoliter-scale phenotypic screening that formulates a chemical library in nanoliter droplet emulsions and automates the construction of chemical combinations en masse using parallel droplet processing. We applied this system to predict synergy between more than 4,000 investigational and approved drugs and a panel of 10 antibiotics against Escherichia coli, a model gram-negative pathogen. We found a range of drugs not previously indicated for infectious disease that synergize with antibiotics. Our validated hits include drugs that synergize with the antibiotics vancomycin, erythromycin, and novobiocin, which are used against gram-positive bacteria but are not effective by themselves to resolve gram-negative infections.

An Argument for Vitamin D, A, and Zinc Monitoring in Cirrhosis.

Malnutrition is prevalent in cirrhosis. Vitamin and mineral deficiencies, including vitamin D, vitamin A, and zinc, are common and have been shown to correlate with survival. Our aim was to review the mechanisms of vitamin D, vitamin A, and zinc deficiencies in cirrhosis and the clinical assessment of affected patients, their outcomes based on the current literature, and management. This is a narrative review including the relevant literature for cirrhosis and vitamin D, vitamin A, and zinc deficiencies. Vitamin D deficiency has important effects in cirrhosis, regardless of the cause of chronic liver disease.These effects include associations with fibrosis and outcomes such as infections, hepatocellular carcinoma, and mortality. Vitamin A deficiency is associated with liver disease progression to cirrhosis and clinical decompensation, including occurrence of ascites or hepatic encephalopathy. Zinc deficiency can lead to hepatic encephalopathy and impaired immune function. Such deficiencies correlate with patient survival and disease severity. Caution should be applied when replacing vitamin D, vitamin A, and zinc to avoid toxicity. Identification and appropriate treatment of vitamin and mineral deficiencies in cirrhosis may reduce specific nutritional and cirrhosis-related adverse events. Routine monitoring of vitamin A, vitamin D and zinc levels in cirrhosis should be considered.

Bariatric Surgery, Clinical Outcomes, and Healthcare Burden in Hispanics in the USA.

INTRODUCTION/PURPOSE: Bariatric surgery (BS) has emerged as a cornerstone procedure to prevent and treat obesity-related comorbidities. As the Hispanic population continues to grow in the USA, their importance to the healthcare system cannot be understated. We aimed to assess the use of BS and related healthcare outcomes in Hispanics using a national database. MATERIALS AND METHODS: Case-control study using the 2010 to 2014 National Inpatient Sample datasets. BS use in Hispanics compared to non-Hispanics was the primary outcome. Secondary outcomes included inpatient mortality, morbidity, resource use, length of hospital stay, hospital costs, and total hospitalization charges. Propensity scores were used to match Hispanic patients with BS with non-Hispanic patients with BS using sex, age, and Charlson Comorbidity Index as covariates. A multivariate model was then used to adjust for additional confounding factors. RESULTS: From the 105,435 patients who underwent BS, a propensity-matched cohort of 20,440 was created (10,945 Hispanics). Mean (SD) age was 45 (17.2) years, and 73,594 (69.8%) were women. The prevalence of BS in Hispanics was 21/100,000 persons (281/100,000 admissions) compared to 36/100,000 persons (337/100,000 admissions) for non-Hispanics. On multivariate analysis, Hispanics displayed adjusted propensity-matched odds of 0.88 of having BS (P < 0.01). No differences were seen in the surgical approach performed. Hispanics and non-Hispanics had similar mortality, morbidity, hospital length of stay, and costs. CONCLUSION: Despite higher obesity rates, the use of BS is lower in Hispanics. For those who underwent BS, no difference in clinical outcomes and minor differences in resource use were observed.

Rapid, Single-Cell Analysis and Discovery of Vectored mRNA Transfection In Vivo with a loxP-Flanked tdTomato Reporter Mouse.

mRNA therapeutics hold promise for the treatment of diseases requiring intracellular protein expression and for use in genome editing systems, but mRNA must transfect the desired tissue and cell type to be efficacious. Nanoparticle vectors that deliver the mRNA are often evaluated using mRNA encoding for reporter genes such as firefly luciferase (FLuc); however, single-cell resolution of mRNA expression cannot generally be achieved with FLuc, and, thus, the transfected cell populations cannot be determined without additional steps or experiments. To more rapidly identify which types of cells an mRNA formulation transfects in vivo, we describe a Cre recombinase (Cre)-based system that permanently expresses fluorescent tdTomato protein in transfected cells of genetically modified mice. Following in vivo application of vectored Cre mRNA, it is possible to visualize successfully transfected cells via Cre-mediated tdTomato expression in bulk tissues and with single-cell resolution. Using this system, we identify previously unknown transfected cell types of an existing mRNA delivery vehicle in vivo and also develop a new mRNA formulation capable of transfecting lung endothelial cells. Importantly, the same formulations with mRNA encoding for fluorescent protein delivered to wild-type mice did not produce sufficient signal for any visualization in vivo, demonstrating the significantly improved sensitivity of our Cre-based system. We believe that the system described here may facilitate the identification and characterization of mRNA delivery vectors to new tissues and cell types.

Efficacy and immunogenicity of unmodified and pseudouridine-modified mRNA delivered systemically with lipid nanoparticles in vivo.

mRNA has broad potential for treating diseases requiring protein expression. However, mRNA can also induce an immune response with associated toxicity. Replacement of uridine bases with pseudouridine has been postulated to modulate both mRNA immunogenicity and potency. Here, we explore the immune response and activity of lipid nanoparticle-formulated unmodified and pseudouridine-modified mRNAs administered systemically in vivo. Pseudouridine modification to mRNA had no significant effect on lipid nanoparticle physical properties, protein expression in vivo, or mRNA immunogenicity compared to unmodified mRNA when delivered systemically with liver-targeting lipid nanoparticles, but reduced in vitro transfection levels. Indicators of a transient, extracellular innate immune response to mRNA were observed, including neutrophilia, myeloid cell activation, and up-regulation of four serum cytokines. This study provides insight into the immune responses to mRNA lipid nanoparticles, and suggests that pseudouridine modifications may be unnecessary for therapeutic application of mRNA in the liver.