Can USMLE and COMLEX-USA Scores Predict At-Risk Emergency Medicine Residents' Performance on In-Training Examinations?

Purpose: The United States Medical Licensing Examination (USMLE) and Comprehensive Osteopathic Medical Licensing Examination (COMLEX) scores are standard methods used to determine residency candidates' medical knowledge. The authors were interested in using the USMLE and COMLEX part 2 scores in our emergency medicine (EM) residency program to identify at-risk residents who may have difficulty on the in-training exam (ITE) and to determine the cutoff values under which an intern could be given an individualized study plan to ensure medical knowledge competency.

Methods: The authors abstracted the USMLE and COMLEX part 2 scores and the American Board of Emergency Medicine (ABEM) ITE scores for a cohort of first-year EM residents graduating years 2010-2022, converting raw scores to percentiles, and compared part 2 and ABEM ITE scores with Pearson's correlation, a Bland-Altman analysis of bias and 95% limits of agreement, and ROC analysis to determine optimal the cut-off values for predicting ABEM ITE < 50 percentile and the estimated test characteristics.

Unravelling High-Molecular-Weight DBP Toxicity Drivers in Chlorinated and Chloraminated Drinking Water: Effect-Directed Analysis of Molecular Weight Fractions.

As disinfection byproducts (DBPs) are ubiquitous sources of chemical exposure in disinfected drinking water, identifying unknown DBPs, especially unknown drivers of toxicity, is one of the major challenges in the safe supply of drinking water. While >700 low-molecular-weight DBPs have been identified, the molecular composition of high-molecular-weight DBPs remains poorly understood. Moreover, due to the absence of chemical standards for most DBPs, it is difficult to assess toxicity contributions for new DBPs identified.

Iodoacetic acid exposure alters the transcriptome in mouse ovarian antral follicles.

Iodoacetic acid (IAA) is an unregulated water disinfection byproduct that is an ovarian toxicant. However, the mechanisms of action underlying IAA toxicity in ovarian follicles remain unclear. Thus, we determined whether IAA alters gene expression in ovarian follicles in mice.

Relationships between regulated DBPs and emerging DBPs of health concern in U.S. drinking water.

A survey was conducted at eight U.S. drinking water plants, that spanned a wide range of water qualities and treatment/disinfection practices.

Formation of regulated and unregulated disinfection byproducts during chlorination and chloramination: Roles of dissolved organic matter type, bromide, and iodide.

Algal blooms and wastewater effluents can introduce algal organic matter (AOM) and effluent organic matter (EfOM) into surface waters, respectively. In this study, the impact of bromide and iodide on the formation of halogenated disinfection byproducts (DBPs) during chlorination and chloramination from various types of dissolved organic matter (DOM, e.g.

Feel the Burn: Disinfection Byproduct Formation and Cytotoxicity during Chlorine Burn Events.

Nitrification and biofilm growth within distribution systems remain major issues for drinking water treatment plants utilizing chloramine disinfection. Many chloraminated plants periodically switch to chlorine disinfection for several weeks to mitigate these issues, known as "chlorine burns". The evaluation of disinfection byproduct (DBP) formation during chlorine burns beyond regulated DBPs is scarce.

Effects of prenatal and lactational exposure to iodoacetic acid on the F1 generation of mice†.

Water disinfection can generate water disinfection byproducts (DBPs). Iodoacetic acid (IAA) is one DBP, and it has been shown to be an ovarian toxicant in vitro and in vivo. However, it is unknown if prenatal and lactational exposure to IAA affects reproductive outcomes in female offspring.

Preferential Halogenation of Algal Organic Matter by Iodine over Chlorine and Bromine: Formation of Disinfection Byproducts and Correlation with Toxicity of Disinfected Waters.

The increasing occurrence of harmful algal blooms (HABs) in surface waters may increase the input of algal organic matter (AOM) in drinking water. The formation of halogenated disinfection byproducts (DBPs) during combined chlorination and chloramination of AOM and natural organic matter (NOM) in the presence of bromide and iodide and haloform formation during halogenation of model compounds were studied. Results indicated that haloform/halogen consumption ratios of halogens reacting with amino acids (representing proteins present in AOM) follow the order iodine > bromine > chlorine, with ratios for iodine generally 1-2 orders of magnitude greater than those for chlorine (0.

Formation of Oleic Acid Chlorohydrins in Vegetables during Postharvest Chlorine Disinfection.

High chlorine doses (50-200 mg/L) are used in postharvest washing facilities to control foodborne pathogen outbreaks. However, chlorine can react with biopolymers (e.g.

Drivers of Disinfection Byproduct Cytotoxicity in U.S. Drinking Water: Should Other DBPs Be Considered for Regulation?

This study reveals key disinfection byproduct (DBP) toxicity drivers in drinking water across the United States. DBPs, which are ubiquitous in drinking water, form by the reaction of disinfectants, organic matter, bromide, and iodide and are generally present at 100-1000× higher concentrations than other contaminants. DBPs are linked to bladder cancer, miscarriage, and birth defects in human epidemiologic studies, but it is not known as to which DBPs are responsible.

Comparison of Estrogenic, Spectroscopic, and Toxicological Analyses of Pilot-Scale Water, Wastewaters, and Processed Wastewaters at Select Military Installations.

Reuse of water requires the removal of contaminants to ensure human health. We report the relative estrogenic activity (REA) of reuse treatment design scenarios for water, wastewaters, and processed wastewaters before and after pilot-scale treatment systems tested at select military facilities. The comparative relationships between REA, several composite toxicological endpoints, and spectroscopic indicators were evaluated for different reuse treatment trains.

Iodoacetic acid affects estrous cyclicity, ovarian gene expression, and hormone levels in mice†.

Iodoacetic acid (IAA) is a water disinfection byproduct that is an ovarian toxicant in vitro. However, information on the effects of IAA on ovarian function in vivo was limited. Thus, we determined whether IAA exposure affects estrous cyclicity, steroidogenesis, and ovarian gene expression in mice.

In vitro effects-based method and water quality screening model for use in pre- and post-distribution treated waters.

Recent urban public water supply contamination events emphasize the importance of screening treated drinking water quality after distribution. In vitro bioassays, when run concurrently with analytical chemistry methods, are effective tools to evaluating the efficacy of water treatment processes and water quality. We tested 49 water samples representing the Chicago Department of Water Management service areas for estrogen, (anti)androgen, glucocorticoid receptor-activating contaminants and cytotoxicity.

Orbital compartment syndrome: Pearls and pitfalls for the emergency physician.

Orbital compartment syndrome (OCS) is a rare, vision-threatening diagnosis that requires rapid identification and immediate treatment for preservation of vision. Because of the time-sensitive nature of this condition, the emergency physician plays a critical role in the diagnosis and management of OCS, which is often caused by traumatic retrobulbar hemorrhage. In this review, we outline pearls and pitfalls for the identification and treatment of OCS, highlighting lateral canthotomy and inferior cantholysis (LCIC), a crucial skill for the emergency physician.

Making Swimming Pools Safer: Does Copper-Silver Ionization with Chlorine Lower the Toxicity and Disinfection Byproduct Formation?

Swimming pools are commonly treated with chlorine, which reacts with the natural organic matter and organic matter introduced by swimmers and form disinfection byproducts (DBPs) that are associated with respiratory-related issues, including asthma, in avid swimmers. We investigated a complementary disinfectant to chlorine, copper-silver ionization (CSI), with the aim of lowering the amount of chlorine used in pools and limiting health risks from DBPs. We sampled an indoor and outdoor pool treated with CSI-chlorine during the swimming season in 2017-2018 and measured 71 DBPs, speciated total organic halogen, mammalian cell cytotoxicity, and -acetyl-l-cysteine (NAC) thiol reactivity as a cytotoxicity predictor.

Toxicity of chlorinated algal-impacted waters: Formation of disinfection byproducts vs. reduction of cyanotoxins.

Seasonal algal blooms in surface waters can impact water quality through an input of algal organic matter (AOM) to the pool of dissolved organic matter as well as the release of cyanotoxins. The formation and speciation of disinfection byproducts (DBPs) during chlorination of algal-impacted waters, collected from growth of Microcystis aeruginosa were studied. Second-order rate constants for the reactions of microcystins (MCs) with chlorine and bromine were determined.