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Understanding the structure and function of nucleic acids in their native environment is crucial to structural biology and one focus of in-cell NMR spectroscopy. Many challenges hamper in-cell NMR in human cell lines, e.g. sample decay through cell death and RNA degradation. The resulting low signal intensities and broad line widths limit the use of more complex NMR experiments, reducing the possible structural and dynamic information that can be extracted. Here, we optimize the detection of imino proton signals, indicators of base-pairing and therefore secondary structure, of a double-stranded DNA oligonucleotide in HeLa cells, using selective excitation. We demonstrate the reproducible quantification of in-cell selective longitudinal relaxation times (selT 1 ), which are reduced compared to the in vitro environment, as a result of interactions with the complex cellular environment. By measuring the intracellular selT 1, we optimize the existing proton pulse sequences, and shorten measurement time whilst enhancing the signal gained per unit of time. This exemplifies an advantage of selective excitation over conventional methods like jump-return water suppression for in-cell NMR. Furthermore, important experimental controls are discussed, including intracellular quantification, supernatant control measurements, as well as the processing of lowly concentrated in-cell NMR samples. We expect that robust and fast in-cell NMR experiments of nucleic acids will facilitate the study of structure and dynamics and reveal their functional correlation., (© 2024. The Author(s).)

Objectives: Postresidency career choices are complex decisions that involve personal, professional, and financial preferences and may be influenced by training programs. It is unknown how residents navigate these decisions during emergency medicine (EM) residency. We explored EM residents' perspectives on career decision making and how residency programs can support career planning., Methods: We conducted semistructured interviews at seven accredited EM residency programs from diverse locations and training formats. We used purposive sampling to reflect the diversity of trainees with regard to gender, level of training, and career plans. Two researchers independently coded the transcripts. We used a constructivist-interpretivist paradigm to guide our thematic analysis., Results: We interviewed 11 residents and identified major themes in three categories. Residents described being exposed to career options through formalized curricula such as required rotations, career fairs, and subspeciality tracks, highlighting the importance of access to faculty with diverse areas of clinical and academic expertise. Many noted that exposure was often self-driven. We identified three major themes regarding career decisions: instrumental factors, people involved, and processes of decision making. Instrumental factors included personal interests, goals, and values as well as practice characteristics, financial considerations, timing, and opportunity costs. Mentors and family were highly involved in resident career decisions. Residents often utilized reflection and conversations with mentors and peers in their decision-making process. Participants recommended that programs provide exposure to diverse career options early in training, protect time for career education, and ensure adequate mentorship and a supportive community. Participants suggested specific curricular content and strategies to support career decisions., Conclusions: This study illuminates important factors involved in resident career decision making and how programs can support their trainees. Essential components include diverse experiences and building a reflective mentorship environment., Competing Interests: The authors declare no conflicts of interest., (© 2024 Society for Academic Emergency Medicine.)

The Pd-catalyzed allylic alkylation of 3,4-disubstituted, racemic cyclobutene electrophiles exhibits a highly unusual stereoselectivity that allows for controlling diastereo- and enantioselectivity only by the choice of ligand and independent of the configuration of the substrate. In order to shed light on the origin of stereoinduction, we performed a systematic mechanistic investigation, including preparation of various putative Pd-allyl intermediates, 1 H/ 31 P NMR reaction monitoring, 2 H-labeling studies, ESI-HRMS and 31 P NMR analysis of reaction mixtures, and DFT structural computations. The mechanism disclosed exhibits several steps with stereospecificities deviating from the commonly accepted "double inversion rule": oxidative addition was found to follow a stereoconvergent course, giving anti -configured η 1 -Pd-cyclobutene species as detectable on-cycle intermediates irrespective of the configuration of starting material, while the subsequent nucleophilic attack features a stereodivergent behavior. In stark contrast to their highly reactive anti -analogues, syn -Pd-cyclobutene complexes that can be formed as side products are rendered entirely unreactive by strong internal Pd-O chelation, preventing the formation of undesired product diastereomers.

Cancer causes psychological distress. Approximately one-third of all patients with cancer suffer from distress requiring psycho-oncological treatment. Examining factors contributing to their distress can inform approaches to counteracting them. Among such factors, resilience is considered to be a psychological adaptive capacity resulting from complex genetic, epigenetic, psychological, and environmental influences. For that reason, we investigated resilience as a factor of psychological distress experience among patients with neuro-oncological disease. To assess distress among patients with neuro-oncological diseases, we performed electronic psycho-oncological screening in the Department of Neurosurgery at Tübingen University Hospital ( n = 100) following tumor surgery (T 0 ) using the Resilience Scale 13, the Hornheider Screening Instrument, the Patient Health Questionnaire-2, the Generalized Anxiety Disorder Scale-2, and the Distress Thermometer, all administered on tablets. Follow-up was done 6 months after (T 1 ). The distress of patients with neuro-oncological disease decreased significantly after 6 months ( p < 0.01). Most patients (87%) showed moderate to high resilience. Although significant correlations with distress are measurable at the T 0 time point (ρ = -0.318 **, p < 0.01), no significant correlations were observed at T 1 . Thus, resilience seems to significantly impact distress in the acute phase of the neuro-oncological disease. For clinical practice, our findings suggest that resilience-focused screening can provide useful information about patients at risk of experiencing distress.

Background: The chief resident role often includes additional administrative and educational experiences beyond those of nonchief senior residents. It is unclear to what extent these experiences influence the postresidency career path of those selected as chief residents. The objective of this study was to evaluate the association of chief resident status on immediate postresidency career characteristics relative to nonchief residents in emergency medicine (EM)., Methods: We retrospectively analyzed graduate data from 2016 to 2020 at six accredited EM residency programs. Participating sites were geographically diverse and included 3- and 4-year training formats. Each site abstracted data using a standardized form including program, year of graduation, chief resident status, publications during residency, and immediate postresidency position (academic vs. nonacademic). We calculated descriptive statistics and performed logistic regression to explore differences between the chief resident cohort and other graduates., Results: We gathered information on 365 total graduates (45.8% from 3-year programs and 54.2% from 4-year programs) including 93 (25.5%) chief residents. A total of 129 (35%) graduates assumed an academic position immediately following residency. Fifty-six (60%) of 93 chief residents assumed an academic position immediately following residency, compared to 74 (27%) of 272 other graduates. After program, year of graduation, and number of publications completed during residency were controlled for, chief resident status was a significant predictor of immediate postresidency academic career (odds ratio for a chief resident assuming an academic job = 5.36, 95% confidence interval = 3.10 to 9.27)., Conclusion: The chief resident role within EM is significantly associated with pursuit of an academic position immediately following residency compared to nonchiefs., Competing Interests: The authors have no potential conflicts to disclose., (© 2021 Society for Academic Emergency Medicine.)

Introduction: Cardiac auscultation skills have proven difficult to train and maintain. The authors investigated whether using phonocardiograms as visual adjuncts to audio cases improved first-year medical students' cardiac auscultation performance., Methods: The authors randomized 135 first-year medical students using an email referral link in 2018 and 2019 to train using audio-only cases (audio group) or audio with phonocardiogram tracings (combined group). Training included 7 cases with normal and abnormal auscultation findings. The assessment included feature identification and diagnostic accuracy using 14 audio-only cases, 7 presented during training, and 7 alternate versions of the same diagnoses. The assessment-administered immediately after training and repeated 7 days later-prompted participants to identify the key features and diagnoses for 14 audio-only cases. Key feature scores and diagnostic accuracy were compared between groups using repeated measures ANOVA., Results: Mean key feature scores were statistically significantly higher in the combined group (70%, 95% CI 67-75%) compared to the audio group (61%, 95% CI 56-66%) (F(1,116) = 6.144, p = 0.015, d s  = 0.45). Similarly, mean diagnostic accuracy in the combined group (68%, 95% CI 62-73%) was significantly higher than the audio group, although with small effect size (59%, 95% CI 54-65%) (F(1,116) = 4.548, p = 0.035, d s  = 0.40). Time on task for the assessment and prior auscultation experience did not significantly impact performance on either measure., Discussion: The addition of phonocardiograms to supplement cardiac auscultation training improves diagnostic accuracy and heart sound feature identification amongst novice students compared to training with audio alone.

For elucidating molecular structure and dynamics in solution, NMR experiments such as NOESY, ROESY and EXSY have been used excessively over the past decades, to provide interatomic distance restraints or rates for chemical exchange. The extraction of such information, however, is often prohibited by signal overlap in these spectra. To reduce this problem, pure shift methods for improving the spectral resolution have become popular. We report on pure shift EASY-ROESY experiments and their application to extract cross-relaxation rates, proton-proton distances and exchange rates. Homonuclear decoupling (pure shift) is applied in the indirect dimension using the PSYCHE or the perfectBASH technique, to enhance the spectral resolution of severely overcrowded spectral regions. The spectral quality is further improved by using a gradient selected F1-PSYCHE-EASY-ROESY, which produces significantly less t 1 -noise than the experiment used previously, as also demonstrated by employing the recently introduced SAN (signal-artefact-noise) plots. Applications include the quantification of distance restraints in a peptide organocatalyst and the extraction of a number of distance restraints in cyclosporine A, which were previously not available for analysis, because they were either located in overcrowded spectral regions or hidden under t 1 -noise. Distances extracted and exchange rates obtained are accurate. Also, the 2D gradient-selected F1-perfectBASH-EASY-ROESY with the additional gradient selection proposed herein, which is superior in terms of sensitivity, can be used to accurately quantify cross-relaxation., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Introduction: Educational podcasts are used by emergency medicine (EM) trainees to supplement clinical learning and to foster a sense of connection to broader physician communities. Yet residents report difficulties remembering what they learned from listening, and the features of podcasts that residents find most effective for learning remain poorly understood. Therefore, we sought to explore residents' perceptions of the design features of educational podcasts that they felt most effectively promoted learning., Methods: We used a qualitative approach to explore EM trainees' experiences with educational podcasts, focusing on design features that they found beneficial to their learning. We conducted 16 semi-structured interviews with residents from three institutions from March 2016-August 2017. Interview transcripts were analyzed line-by-line using constant comparison and organized into focused codes, conceptual categories, and then key themes., Results: The five canons of classical rhetoric provided a framework for thematically grouping the disparate features of podcasts that residents reported enhanced their learning. Specifically, they reported valuing the following: 1) Invention: clinically relevant material presented from multiple perspectives with explicit learning points; 2) Arrangement: efficient communication; 3) Style: narrative incorporating humor and storytelling; 4) Memory: repetition of key content; and 5) Delivery: short episodes with good production quality., Conclusion: This exploratory study describes features that residents perceived as effective for learning from educational podcasts and provides foundational guidance for ongoing research into the most effective ways to structure medical education podcasts.

Case Presentation: A 55-year-old woman with a history of end-stage renal disease, peripheral vascular disease, and multiple prior abdominal surgeries presented to the emergency department with three days of diffuse, severe, abdominal pain with accompanying nausea, emesis, and food intolerance. A computed tomography (CT) of her abdomen demonstrated a "whirl" of small bowel and mesenteric vessels, raising suspicion for mesenteric volvulus and resultant small bowel obstruction., Discussion: Mesenteric volvulus is a low incidence, high mortality condition; therefore, early recognition and operative intervention are critical. Patients with a "whirl sign" on CT are more likely to require surgical intervention for their small bowel obstruction.

Residual dipolar couplings (RDCs) are amongst the most powerful NMR parameters for organic structure elucidation. In order to maximize their effectiveness in increasingly complex cases such as flexible compounds, a maximum of RDCs between nuclei sampling a large distribution of orientations is needed, including sign information. For this, the easily accessible one-bond 1 H- 13 C RDCs alone often fall short. Long-range 1 H- 1 H RDCs are both abundant and typically sample highly complementary orientations, but accessing them in a sign-sensitive way has been severely obstructed due to the overflow of 1 H- 1 H couplings. Here, we present a generally applicable strategy that allows the measurement of a large number of 1 H- 1 H RDCs, including their signs, which is based on a combination of an improved PSYCHEDELIC method and a new selective constant-time β-COSY experiment. The potential of 1 H- 1 H RDCs to better determine molecular alignment and to discriminate between enantiomers and diastereomers is demonstrated., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

While multiple theories exist to explain the diagnostic process, there are few available assessments that reliably determine diagnostic competence in trainees. Most methods focus on aspects of the process of diagnostic reasoning, such as the relation between case features and diagnostic hypotheses. Inevitably, detailed elucidation of aspects of the process requires substantial time per case and limits the number of cases that can be examined given a limited testing time. Shifting assessment to the outcome of diagnostic reasoning, accuracy of the diagnosis, may serve as a reliable measure of diagnostic competence and would allow increased sampling across cases. The present study is a retrospective analysis of 7 large studies, conducted by 3 research teams, that all used a series of brief written cases to examine the outcome of diagnostic reasoning-the diagnosis. The studies involved over 600 clinicians ranging from final year medical students to practicing emergency physicians. For 4 studies with usable reliability data, reliability for a 2 h test ranged from .63 to .94. On average speeded tests were more reliable (.85 vs. .73).To achieve a reliability of .75 required an average test time of 1.11 h for speeded tests and 1.99 for unspeeded tests. The measure was shown to be positively correlated with both written knowledge tests and measures of problem solving derived from OSCE performance tests. This retrospective analysis provides evidence to support the implementation of outcome-based assessments of clinical reasoning.

Band selective techniques offer the highest sensitivity of all pure shift approaches and thus are the best choice for decoupling well-separated 1 H-frequency regions, such as the amide- or the α-proton region of α-peptides. They are inept to fully decouple the amide- and the α-proton region simultaneously, though. Herein, we present a new homonuclear decoupling technique, which extends the capabilities of band selective decoupling using the perfect echo principle. This modification allows a complete backbone decoupling (amide- and α-protons) in peptides and opens band selective homonuclear decoupling to substances with two mutually coupled protons in the spectral range of interest., (© 2018 John Wiley & Sons, Ltd.)

Motivated by the persisting need for enhanced resolution in solution state NMR spectra, pure shift techniques such as Zangger-Sterk decoupling have recently attracted widespread interest. These techniques for homonuclear decoupling offer enhanced resolution in one- and multidimensional proton detected experiments by simplifying multiplet structures. In this work, a modification to the popular Zangger-Sterk technique PEPSIE (Perfect Echo Pure Shift Improved Experiment) is presented, which decouples pairs of spins even if they share the same volume element. This in turn can drastically improve the sensitivity, as compared to classical Zangger-Sterk decoupling, as larger volume elements can be used to collect the detected signal. Most interestingly, even in the presence of moderate strong coupling, the PEPSIE experiment produces clean and widely artifact free spectra. In order to better understand this - to us initially - surprising behaviour we performed analyses using numerical simulations and derived an (approximate) analytical solution from density matrix formalism. We show that this experiment is particularly suitable to study samples with strong signal clustering, a situation which can render classic Zangger-Sterk decoupling inefficient., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Introduction: Peer review, a cornerstone of academia, promotes rigor and relevance in scientific publishing. As educators are encouraged to adopt a more scholarly approach to medical education, peer review is becoming increasingly important. Junior educators both receive the reviews of their peers, and are also asked to participate as reviewers themselves. As such, it is imperative for junior clinician educators to be well-versed in the art of peer reviewing their colleagues' work. In this article, our goal was to identify and summarize key papers that may be helpful for faculty members interested in learning more about the peer-review process and how to improve their reviewing skills., Methods: The online discussions of the 2016-17 Academic Life in Emergency Medicine (ALiEM) Faculty Incubator program included a robust discussion about peer review, which highlighted a number of papers on that topic. We sought to augment this list with further suggestions by guest experts and by an open call on Twitter for other important papers. Via this process, we created a list of 24 total papers on the topic of peer review. After gathering these papers, our authorship group engaged in a consensus-building process incorporating Delphi methods to identify the papers that best described peer review, and also highlighted important tips for new reviewers., Results: We found and reviewed 24 papers. In our results section, we present our authorship group's top five most highly rated papers on the topic of peer review. We also summarize these papers with respect to their relevance to junior faculty members and to faculty developers., Conclusion: We present five key papers on peer review that can be used for faculty development for novice writers and reviewers. These papers represent a mix of foundational and explanatory papers that may provide some basis from which junior faculty members might build upon as they both undergo the peer-review process and act as reviewers in turn., Competing Interests: Conflicts of Interest: By the WestJEM article submission agreement, all authors are required to disclose all affiliations, funding sources and financial or management relationships that could be perceived as potential sources of bias. No author has professional or financial relationships with any companies that are relevant to this study. There are no conflicts of interest or sources of funding to declare.

Background: Many authors have implicated cognitive biases as a primary cause of diagnostic error. If this is so, then physicians already familiar with common cognitive biases should consistently identify biases present in a clinical workup. The aim of this paper is to determine whether physicians agree on the presence or absence of particular biases in a clinical case workup and how case outcome knowledge affects bias identification., Methods: We conducted a web survey of 37 physicians. Each participant read eight cases and listed which biases were present from a list provided. In half the cases the outcome implied a correct diagnosis; in the other half, it implied an incorrect diagnosis. We compared the number of biases identified when the outcome implied a correct or incorrect primary diagnosis. Additionally, the agreement among participants about presence or absence of specific biases was assessed., Results: When the case outcome implied a correct diagnosis, an average of 1.75 cognitive biases were reported; when incorrect, 3.45 biases (F=71.3, p<0.00001). Individual biases were reported from 73% to 125% more often when an incorrect diagnosis was implied. There was no agreement on presence or absence of individual biases, with κ ranging from 0.000 to 0.044., Interpretation: Individual physicians are unable to agree on the presence or absence of individual cognitive biases. Their judgements are heavily influenced by hindsight bias; when the outcome implies a diagnostic error, twice as many biases are identified. The results present challenges for current error reduction strategies based on identification of cognitive biases., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.)

We report on a detailed NMR spectroscopic study of the catalyst-substrate interaction of a highly enantioselective oligopeptide catalyst that is used for the kinetic resolution of trans-cycloalkane-1,2-diols via monoacylation. The extraordinary selectivity has been rationalized by molecular dynamics as well as density functional theory (DFT) computations. Herein we describe the conformational analysis of the organocatalyst studied by a combination of nuclear Overhauser effect (NOE) and residual dipolar coupling (RDC)-based methods that resulted in an ensemble of four final conformers. To corroborate the proposed mechanism, we also investigated the catalyst in mixtures with both trans-cyclohexane-1,2-diol enantiomers separately, using advanced NMR methods such as T 1 relaxation time and diffusion-ordered spectroscopy (DOSY) measurements to probe molecular aggregation. We determined intramolecular distance changes within the catalyst after diol addition from quantitative NOE data. Finally, we developed a pure shift EASY ROESY experiment using PSYCHE homodecoupling to directly observe intermolecular NOE contacts between the trans-1,2-diol and the cyclohexyl moiety of the catalyst hidden by spectral overlap in conventional spectra. All experimental NMR data support the results proposed by earlier computations including the proposed key role of dispersion interaction., (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Objectives: This study's objectives were to assess administration of a rapidly dissolving transbuccal fentanyl tablet to patients in emergency department (ED) with orthopedic extremity pain. The main end point was time required to achieve a 2-point drop on a 0 to 10 pain scale., Methods: In this double-blind trial, subjects received either transbuccal fentanyl, 100 μg, and a swallowed placebo, or a swallowed oxycodone/acetaminophen, 5/325-mg pill, and a nonanalgesic transbuccal comparator. Pain assessment occurred every 5 minutes for an hour, and vital signs were monitored for 2 hours., Results: Transbuccal fentanyl was associated with faster pain relief onset (median, 10 vs 35 minutes; P < .0001). Secondary end points (pain relief magnitude, rescue medication rate, subject preference for medication on future visit) favored transbuccal fentanyl. No vital sign abnormalities or significant side effects occurred in the ED or on 100% next-day follow-up., Conclusions: Transbuccal fentanyl shows promise for continued investigation as a means to safely provide rapid and effective pain relief for ED patients., (Copyright © 2010 Elsevier Inc. All rights reserved.)