Student Expenses in Residency Interviewing

Introduction. The student costs of residency interviewing areof increasing concern but limited current information is available.Updated, more detailed information would assist studentsand residency programs in decisions about residency selection.The study objective was to measure the expenses and time spentin residency interviewing by the 2016 graduating class of the Universityof Kansas School of Medicine and assess the impact ofgender, regional campus location, and primary care application. Methods. All 195 students who participated in the 2016 NationalResidency Matching Program (NRMP) received a 33 item questionnaireaddressing interviewing activity, expenses incurred, timeinvested and related factors. Main measures were self-reported estimatesof expenses and time spent interviewing. Descriptive analyseswere applied to participant characteristics and responses. Multivariateanalysis of variance (MANOVA) and chi-square tests comparedstudents by gender, campus (main/regional), and primary care/other specialties. Analyses of variance (ANOVA) on the dependentvariables provided follow-up tests on significant MANOVA results. Results. A total of 163 students (84%) completed the survey. Theaverage student reported 38 (1 - 124) applications, 16 (1 - 54) invitations,11 (1 - 28) completed interviews, and spent $3,500($20 - $12,000) and 26 (1 - 90) days interviewing. No significantdifferences were found by gender. After MANOVA and ANOVAanalyses, non-primary care applicants reported significantlymore applications, interviews, and expenditures, butless program financial support. Regional campus students reportedsignificantly fewer invitations, interviews, and daysinterviewing, but equivalent costs when controlled for primarycare application. Cost was a limiting factor in acceptinginterviews for 63% and time for 53% of study respondents. Conclusions. Students reported investing significant time andmoney in interviewing. After controlling for other variables, primarycare was associated with significantly lowered expenses.Regional campus location was associated with fewer interviewsand less time interviewing. Gender had no significantimpact on any aspect studied. KS J Med 2017;10(3):50-54

Identification of Small Molecule Inhibitors of Tau Aggregation by Targeting Monomeric Tau As a Potential Therapeutic Approach for Tauopathies.

A potential strategy to alleviate the aggregation of intrinsically disordered proteins (IDPs) is to maintain the native functional state of the protein by small molecule binding. However, the targeting of the native state of IDPs by small molecules has been challenging due to their heterogeneous conformational ensembles. To tackle this challenge, we applied a high-throughput chemical microarray surface plasmon resonance imaging screen to detect the binding between small molecules and monomeric full-length Tau, a protein linked with the onset of a range of Tauopathies. The screen identified a novel set of drug-like fragment and lead-like compounds that bound to Tau. We verified that the majority of these hit compounds reduced the aggregation of different Tau constructs in vitro and in N2a cells. These results demonstrate that Tau is a viable receptor of drug-like small molecules. The drug discovery approach that we present can be applied to other IDPs linked to other misfolding diseases such as Alzheimer's and Parkinson's diseases.We thank the Wellcome Trust (UK), Medical Research Council (UK), Elan Pharmaceuticals (USA), the Canadian Institutes of Health Research (Canada) and the Alzheimer Society of Ontario (Canada), and Hungarian Brain Research Program (KTIA_NAP_13-2014-0009) for funding.This is the author accepted manuscript. The final version is available from Bentham Science via http://dx.doi.org/10.2174/15672050120915101910495

Targeting the Intrinsically Disordered Structural Ensemble of a-Synuclein by Small Molecules as a Potential Therapeutic Strategy for Parkinson's Disease

Abstract The misfolding of intrinsically disordered proteins such as a-synuclein, tau and the Ab peptide has been associated with many highly debilitating neurodegenerative syndromes including Parkinson's and Alzheimer's diseases. Therapeutic targeting of the monomeric state of such intrinsically disordered proteins by small molecules has, however, been a major challenge because of their heterogeneous conformational properties. We show here that a combination of computational and experimental techniques has led to the identification of a drug-like phenyl-sulfonamide compound (ELN484228), that targets a-synuclein, a key protein in Parkinson's disease. We found that this compound has substantial biological activity in cellular models of a-synuclein-mediated dysfunction, including rescue of a-synuclein-induced disruption of vesicle trafficking and dopaminergic neuronal loss and neurite retraction most likely by reducing the amount of a-synuclein targeted to sites of vesicle mobilization such as the synapse in neurons or the site of bead engulfment in microglial cells. These results indicate that targeting a-synuclein by small molecules represents a promising approach to the development of therapeutic treatments of Parkinson's disease and related conditions

Mechanism and regulation of the protein kinase ERK2

textThe extracellular signal-regulated kinase 2 (ERK2) cascade plays important roles in a variety of cellular events such as proliferation, differentiation, and apoptosis. Involvement in such diverse cellular processes demands that this signal transduction pathway be strictly controlled. The fact that perturbations in the ERK2 signaling pathway are associated with a variety of diseases only further emphasizes the importance of maintaining the fidelity of the signaling cascade. In order to understand the mechanism of signal transduction fidelity, the kinetic mechanism and protein-protein interactions of ERK2 have been examined. In Chapter 1, a fluorescence anisotropy assay was developed to monitor the protein-protein interactions that occur between ERK2 and potential substrates. Results from these studies demonstrate that the phosphorylation status of ERK2 can alter protein-protein interactions. In Chapter 2, stopped-flow fluorescence spectroscopy studies demonstrate that the binding of EtsΔ138 to ERK2 follows a two-step mechanism in which binding occurs first followed by a conformational change. The results also suggest that substrate binding does not involve the active site, but instead occurs through the interaction of ERK2 docking-recruiting sites with EtsΔ138 docking motifs. In Chapter 3, transient kinetic methods were used to identify the second rate-limiting step in the ERK2 reaction pathway. The experiments provided evidence that an ADP dissociation step partially limiting enzymatic turnover. In Chapter 4, the magnesium effects on the catalytic mechanism of ERK2 were investigated. According to the study, ERK2 utilizes a second Mg2+ ion to facilitate ternary complex formation and catalysis, without inhibiting MgADP release, which is partially rate-limiting. The molecular basis for magnesium activation was found to stem from the interaction of the second Mg2+ ion by Asn-152. In Chapter 5, the interaction between ERK2 and PEA-15 was analyzed and PEA-15 was found to act as an inhibitor of ERK2- D-site interactions by binding to ERK2 via a proposed D-site motif. Further examination revealed that the neither the activation state of ERK2 nor the phosphorylation of PEA-15 has an affect on the affinity of these two proteins for one another.Chemistry and BiochemistryBiochemistr

The Effect of Arrestin Conformation on the Recruitment of c-Raf1, MEK1, and ERK1/2 Activation

Sergio Coffa is with Vanderbilt University; Maya Breitman is with Vanderbilt University; Susan M. Hanson is with Vanderbilt University; Seunghyi Kook is with Vanderbilt University; Vsevolod V. Gurevich is with Vanderbilt University; Kari Callaway is with UT Austin; Kevin N. Dalby is with UT Austin.Arrestins are multifunctional signaling adaptors originally discovered as proteins that “arrest” G protein activation by G protein-coupled receptors (GPCRs). Recently GPCR complexes with arrestins have been proposed to activate G protein-independent signaling pathways. In particular, arrestin-dependent activation of extracellular signal-regulated kinase 1/2 (ERK1/2) has been demonstrated. Here we have performed in vitro binding assays with pure proteins to demonstrate for the first time that ERK2 directly binds free arrestin-2 and -3, as well as receptor-associated arrestins-1, -2, and -3. In addition, we showed that in COS-7 cells arrestin-2 and -3 association with β2-adrenergic receptor (β2AR) significantly enhanced ERK2 binding, but showed little effect on arrestin interactions with the upstream kinases c-Raf1 and MEK1. Arrestins exist in three conformational states: free, receptor-bound, and microtubule-associated. Using conformationally biased arrestin mutants we found that ERK2 preferentially binds two of these: the “constitutively inactive” arrestin-Δ7 mimicking microtubule-bound state and arrestin-3A, a mimic of the receptor-bound conformation. Both rescue arrestin-mediated ERK1/2/activation in arrestin-2/3 double knockout fibroblasts. We also found that arrestin-2-c-Raf1 interaction is enhanced by receptor binding, whereas arrestin-3-c-Raf1 interaction is not.Funding was provided by National Institutes of Health grants GM081756, GM077561, and EY011500 (VVG), and GM059802 and the Welch Foundation (F-1390) (KND). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Pharmac