The Timing, Factors, and Impact of USMLE Step 1 Becoming Pass/Fail on the Process of Choosing a Specialty.

Background  Choosing a medical specialty is an important decision. A combination of factors influenced this decision. Student characteristics and examination performances can influence this decision. With the transition of the United States Medical Licensing Examination (USMLE) Step 1 becoming pass/fail, it is important to analyze the specialty decision process. Objective The purpose of this multimethod study is to assess when in the curriculum students choose a specialty, what factors influence their decision, and the impact of USMLE Step 1 scores on a student's assessment of competitiveness. Methods In February 2022, a survey was prepared and approved by the University of Nevada, Las Vegas (UNLV) Institutional Review Board (IRB). The survey contained multiple-choice questions and a free-response section. The survey was sent to the Class of 2022 and 2023 students at Kirk Kerkorian School of Medicine who follow a Longitudinal Integrated Clerkship. Descriptive statistics and one-sample t-tests were calculated. Results A total of 89 students completed the survey: 42 out of 60 students (70%) from the Class of 2022 and 47 out of 61 students (77%) from the Class of 2023. This study found that 78.8% of longitudinal interleaved clerkship (LInC) students committed to their specialty during the second half of the clinical year. The effects of positive and negative experiences during clerkships were most significantly different (p < 0.001). Conclusion The majority of LInC students arrive at their decision by the latter half of the clinical year. A variety of factors help students arrive at their decision. Our findings suggest that the pass/fail grading system will make it more difficult for students to assess their personal competitiveness.

Remdesivir-associated bradycardia in COVID-19: a rapid review protocol.

INTRODUCTION: Remdesivir is an antiviral medication that is used in the treatment of severe COVID-19. Research has highlighted the potential cardiac side effects of remdesivir, including the occurrence of remdesivir-associated bradycardia (RAB), but these findings have not been consistent. In addition, very little is known about the clinical implications and outcomes of RAB. The aim of this rapid systematic review is to determine the event rate of developing bradycardia while receiving remdesivir treatment compared with not receiving remdesivir in patients diagnosed with COVID-19. METHODS AND ANALYSIS: This study follows the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocol guidelines and will include original papers related to COVID-19, remdesivir and bradycardia. Only English language papers published from 1 December 2019 to 31 December 2022 will be included. The following databases will be searched using keywords and controlled vocabulary: Ovid MEDLINE, Ovid EMBASE, Scopus, Cochrane, PubMed and Web of Science. Two reviewers will independently perform screening and data abstraction. Data will be synthesised qualitatively as well as quantitatively. A random-effects model will be used to calculate the pooled estimates. ETHICS AND DISSEMINATION: This review will systematically analyse the clinical studies available to help better characterise RAB. The results will support a retrospective study investigating RAB that is currently being conducted at the University Medical Center of Southern Nevada in Las Vegas, Nevada. PROSPERO REGISTRATION NUMBER: This protocol has been submitted to and approved by PROSPERO (Protocol ID: CRD42022331614).

Closing the Gap Between Mammalian and Invertebrate Peripheral Nerve Injury: Protocol for a Novel Nerve Repair.

BACKGROUND: Outcomes after peripheral nerve injuries are poor despite current nerve repair techniques. Currently, there is no conclusive evidence that mammalian axons are capable of spontaneous fusion after transection. Notably, certain invertebrate species are able to auto-fuse after transection. Although mammalian axonal auto-fusion has not been observed experimentally, no mammalian study to date has demonstrated regenerating axolemmal membranes contacting intact distal segment axolemmal membranes to determine whether mammalian peripheral nerve axons have the intrinsic mechanisms necessary to auto-fuse after transection. OBJECTIVE: This study aims to assess fusion competence between regenerating axons and intact distal segment axons by enhancing axon regeneration, delaying Wallerian degeneration, limiting the immune response, and preventing myelin obstruction. METHODS: This study will use a rat sciatic nerve model to evaluate the effects of a novel peripheral nerve repair protocol on behavioral, electrophysiologic, and morphologic parameters. This protocol consists of a variety of preoperative, intraoperative, and postoperative interventions. Fusion will be assessed with electrophysiological conduction of action potentials across the repaired transection site. Axon-axon contact will be assessed with transmission electron microscopy. Behavioral recovery will be analyzed with the sciatic functional index. A total of 36 rats will be used for this study. The experimental group will use 24 rats and the negative control group will use 12 rats. For both the experimental and negative control groups, there will be both a behavior group and another group that will undergo electrophysiological and morphological analysis. The primary end point will be the presence or absence of action potentials across the lesion site. Secondary end points will include behavioral recovery with the sciatic functional index and morphological analysis of axon-axon contact between regenerating axons and intact distal segment axons. RESULTS: The author is in the process of grant funding and institutional review board approval as of March 2020. The final follow-up will be completed by December 2021. CONCLUSIONS: In this study, the efficacy of the proposed novel peripheral nerve repair protocol will be evaluated using behavioral and electrophysiologic parameters. The author believes this study will provide information regarding whether spontaneous axon fusion is possible in mammals under the proper conditions. This information could potentially be translated to clinical trials if successful to improve outcomes after peripheral nerve injury. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/18706.

Direct Conversion of Cellulose into Ethyl Lactate in Supercritical Ethanol-Water Solutions.

Biomass-derived ethyl lactate is a green solvent with a growing market as the replacement for petroleum-derived toxic organic solvents. Here we report, for the first time, the production of ethyl lactate directly from cellulose with the mesoporous Zr-SBA-15 silicate catalyst in a supercritical mixture of ethanol and water. The relatively strong Lewis and weak Brønsted acid sites on the catalyst, as well as the surface hydrophobicity, were beneficial to the reaction and led to synergy during consecutive reactions, such as depolymerization, retro-aldol condensation, and esterification. Under the optimum reaction conditions, ∼33 % yield of ethyl lactate was produced from cellulose with the Zr-SBA-15 catalyst at 260 °C in supercritical 95:5 (w/w) ethanol/water.

Defining Optimal Head-Tilt Position of Resuscitation in Neonates and Young Infants Using Magnetic Resonance Imaging Data.

Head-tilt maneuver assists with achieving airway patency during resuscitation. However, the relationship between angle of head-tilt and airway patency has not been defined. Our objective was to define an optimal head-tilt position for airway patency in neonates (age: 0-28 days) and young infants (age: 29 days-4 months). We performed a retrospective study of head and neck magnetic resonance imaging (MRI) of neonates and infants to define the angle of head-tilt for airway patency. We excluded those with an artificial airway or an airway malformation. We defined head-tilt angle a priori as the angle between occipito-ophisthion line and ophisthion-C7 spinous process line on the sagittal MR images. We evaluated medical records for Hypoxic Ischemic Encephalopathy (HIE) and exposure to sedation during MRI. We analyzed MRI of head and neck regions of 63 children (53 neonates and 10 young infants). Of these 63 children, 17 had evidence of airway obstruction and 46 had a patent airway on MRI. Also, 16/63 had underlying HIE and 47/63 newborn infants had exposure to sedative medications during MRI. In spontaneously breathing and neurologically depressed newborn infants, the head-tilt angle (median ± SD) associated with patent airway (125.3° ± 11.9°) was significantly different from that of blocked airway (108.2° ± 17.1°) (Mann Whitney U-test, p = 0.0045). The logistic regression analysis showed that the proportion of patent airways progressively increased with an increasing head-tilt angle, with > 95% probability of a patent airway at head-tilt angle 144-150°.