Describing the Physician Associate Clinical Training Site Compensation Market.

INTRODUCTION: Inadequate clinical training site availability may inhibit physician assistant/associate (PA), advanced practice nursing (APN), and physician workforce growth. Educational institutions increasingly incentivize clinical training sites with financial compensation, with potential implications for educational costs and enrollment. This study investigated compensation trends among PA programs. METHODS: Data from the 2013 to 2019 PA Education Association Program Reports were examined. Multivariate logistic and linear regressions were estimated to identify the influence of PA program characteristics on clinical training site compensation. The effect of compensation on program enrollment was determined with a difference-in-differences estimator. RESULTS: Physician assistant/associate programs collectively paid nearly $19 million to clinical training sites in 2019. The percentage of programs that offer financial incentives increased from 22.2% in 2013 to 52.3% in 2019. Over this time, public institutions affiliated with academic health centers (AHCs) were least likely to offer compensation. Higher compensation rates were observed in Census divisions with greater number of programs, and programs located in New England were the most likely to offer compensation. Offering compensation did not influence growth in programs' enrollment. DISCUSSION: Compensation trends highlight increasing demand for PA clinical training sites, especially in areas with greater regional competition. Compensation is primarily driven by private institutions unaffiliated with AHCs. Programs likely offer compensation to maintain, rather than grow, enrollment. Additional investigation should incorporate medical school and APN program data to more fully examine the impact of these costs on learners, institutions, and the health care workforce.

Prevalence of Decay and Tooth Condition Changes Adjacent to Restored Dental Implants: A Retrospective Radiographic Study.

This study examined the association between a dental implant and changes in adjacent teeth over time. Electronic health records of 1818 patients who received a dental implant were retrospectively evaluated over 14 years (2005-2019) in a university setting. The status of the adjacent tooth and vertical and horizontal distance from the implant platform to adjacent teeth were determined using digital intraoral radiographs taken at baseline and the last follow-up visit (1-14 years, median four years). In total, 1085 dental implants were evaluated. There were 234 instances of a change in the adjacent tooth. Decay was observed in 83 (7.6%) of adjacent teeth; the mean time to development was four years (range 1 to 14 years). Approximately 9% of adjacent teeth received direct restorations, 4.8% received indirect restorations, 1% received endodontic root canal treatment (RCT), and 5.6% were extracted. The mean horizontal distance between the implant platform and the adjacent teeth was 3.56 mm; the mean vertical distance from the contact point to the alveolar crest on the tooth side was 6.2 mm at the 1st time of the reported decay on x-ray. These distances did not significantly influence the occurrence of caries. The prevalence of interproximal contact loss (ICL) was higher on the mesial of the implant crown at 63% compared to 20% on the distal side. This large retrospective analysis identified that teeth adjacent to a dental implant were at risk of decay and changes in their condition. In addition, the implant-to-tooth distance and inadequate emergence profile may contribute as caries risk factors in addition to hygiene and a high sugar level diet. These findings appear essential for clinicians when making treatment decisions and discussing outcomes with patients.

Older adults' perceptions of ageism, discrimination, and racism.

Older adults often experience different forms of discrimination, whether it be on the basis of their age, gender, race, or ethnicity (Rochon et al. 2021). Many older adults have stated they have experienced the health care system differently because of their race or ethnicity . Understanding older adults' experiences and their perceptions of ageism and racism can guide future work. This observational cross-sectional study captured community-dwelling older adults' perceptions about their experiences with ageism and racism. A few opened-ended questions were included in the cross-sectional survey. While results did not yield differences with respect to perceptions of ageism by race; there were statistically significant results in regard to perceived racism, with higher scores on the racism scales for individuals who self-identified as Black. Discussion and implications for practice, policy and research are explored.

Dependent Competing Failure Processes in Reliability Systems.

This paper deals with a reliability system hit by three types of shocks ranked as harmless, critical, or extreme, depending on their magnitudes, being below H1, between H1 and H2, and above H2, respectively. The system's failure is caused by a single extreme shock or by a total of N critical shocks. In addition, the system fails under occurrences of M pairs of shocks with lags less than some δ (δ-shocks) in any order. Thus, the system fails when one of the three named cumulative damages occurs first. Thus, it fails due to the competition of the three associated shock processes. We obtain a closed-form joint distribution of the time-to-failure, shock count upon failure, δ-shock count, and cumulative damage to the system on failure, to name a few. In particular, the reliability function directly follows from the marginal distribution of the failure time. In a modified system, we restrict δ-shocks to those with small lags between consecutive harmful shocks. We treat the system as a generalized random walk process and use an embellished variant of discrete operational calculus developed in our earlier work. We demonstrate analytical tractability of our formulas which are also validated, through Monte Carlo simulation.

Risk Factors for Trochanteric Bursitis Following Total Hip Arthroplasty: A Radiographic Analysis.

BACKGROUND: Trochanteric bursitis (TB) is a prevalent complication following total hip arthroplasty (THA), with increased offset hypothesized as a potential risk factor. This study investigated potential TB predictors in THA patients, including radiographic measurements of offset and leg length, comorbidities, and patient characteristics. METHODS: In this retrospective cohort study, all THA patients from a single academic tertiary care center between 2005 and 2021 were reviewed. Exclusion criteria included less than one-year follow-up, osteonecrosis, or fracture. Manual radiographic measurements of offset (acetabular, femoral, and total) and leg length from preoperative and postoperative antero-posterior pelvis X-rays were taken, with scaling using femoral cortical diameter. Univariable and multivariable Cox proportional hazard models were employed to estimate TB risk. RESULTS: Of 1,094 patients, 103 (9.4%) developed TB, with a median (Q1, Q3) time to presentation of 41.8 weeks (25.5, 66.9). In univariable models, only sex was associated with increased TB risk, with women exhibiting a 1.79 times increased risk (hazard ratio: 1.79 (1.16, 2.76), P = .009). Changes in acetabular offset, femoral offset, total offset, and leg length between preoperative and postoperative radiographs were not associated with an increased risk of developing TB in the univariate or multivariate models. Furthermore, various offset thresholds were evaluated, with no amount of increased offset showing increased TB risk. CONCLUSIONS: This study found no relationship between femoral, acetabular, or total offset and TB following THA. These findings suggest that surgeons may consider adding offset for increased prosthetic stability in high-risk cases. However, given that this is a retrospective study, the authors are not advocating for the routine use of increased offset. The study identified women as a risk factor with a 1.79 times higher TB risk, highlighting the importance of counseling women patients on this heightened risk.

Utilization of Spontaneous Alkyne-Gold Self-Assembly Chemistry as an Alternative Method for Fabricating Electrochemical Aptamer-Based Sensors.

Electrochemical aptamer-based (E-AB) sensors are a promising class of biosensors which use structure-switching redox-labeled oligonucleotides (aptamers) codeposited with passivating alkanethiol monolayers on electrode surfaces to specifically bind and detect target analytes. Signaling in E-AB sensors is an outcome of aptamer conformational changes upon target binding, with the sequence of the aptamer imparting specificity toward the analyte of interest. The change in conformation translates to a change in electron transfer between the redox label attached to the aptamer and the underlying electrode and is related to analyte concentration, allowing specific electrochemical detection of nonelectroactive analytes. E-AB sensor measurements are reagentless with time resolutions of seconds or less and may be miniaturized into the submicron range. Traditionally these sensors are fabricated using thiol-on-gold chemistry. Here we present an alternate immobilization chemistry, gold-alkyne binding, which results in an increase in sensor lifetimes under ideal conditions by up to ∼100%. We find that gold-alkyne binding is spontaneous and supports efficient E-AB sensor signaling with analytical performance characteristics similar to those of thiol generated monolayers. The surface modification differs from gold-thiol binding only in the time and aptamer concentration required to achieve similar aptamer surface coverages. In addition, alkynated aptamers differ from their thiolated analogues only by their chemical handle for surface attachment, so any existing aptamers can be easily adapted to utilize this attachment strategy.

DrugMap: A quantitative pan-cancer analysis of cysteine ligandability.

Cysteine-focused chemical proteomic platforms have accelerated the clinical development of covalent inhibitors for a wide range of targets in cancer. However, how different oncogenic contexts influence cysteine targeting remains unknown. To address this question, we have developed "DrugMap," an atlas of cysteine ligandability compiled across 416 cancer cell lines. We unexpectedly find that cysteine ligandability varies across cancer cell lines, and we attribute this to differences in cellular redox states, protein conformational changes, and genetic mutations. Leveraging these findings, we identify actionable cysteines in NF-κB1 and SOX10 and develop corresponding covalent ligands that block the activity of these transcription factors. We demonstrate that the NF-κB1 probe blocks DNA binding, whereas the SOX10 ligand increases SOX10-SOX10 interactions and disrupts melanoma transcriptional signaling. Our findings reveal heterogeneity in cysteine ligandability across cancers, pinpoint cell-intrinsic features driving cysteine targeting, and illustrate the use of covalent probes to disrupt oncogenic transcription-factor activity.

Single Voltammetric Sweep Calibration-Free Interrogation of Electrochemical Aptamer-Based Sensors Employing Continuous Square Wave Voltammetry.

Continuous square wave voltammetry (cSWV) is a technique that enables the continuous collection of current data (at 100 kHz) to maximize the information content obtainable from a single voltammetric sweep. This data collection procedure results in the generation of multiple voltammograms corresponding to different effective square wave frequencies. The application of cSWV brings significant benefits to electrochemical aptamer-based (E-AB) sensors. The E-AB sensor platform permits continuous real-time monitoring of small biological molecules. Traditionally, E-AB sensors report only on changes in analyte concentration rather than absolute quantification in matrices when basal concentrations are not known a priori. This is because they exhibit a voltammetric peak current even in the absence of a target. However, using a dual-frequency approach, calibration-free sensing can be performed effectively, eliminating the sensor-to-sensor variation by taking ratiometric current responses obtained at two different frequencies from two different voltammetric sweeps. In employing our approach, cSWV provides a great advantage over the conventionally used square wave voltammetry since the required voltammograms are collected with a single sweep, which improves the temporal resolution of the measurement when considering the current at multiple frequencies for improved accuracy and reduced surface interrogation. Moreover, we show here that using cSWV provides significantly improved concentration predictions. E-AB sensors sensitive to ATP and tobramycin were interrogated across a wide range of concentrations. With this approach, cSWV allowed us to estimate the target concentration, retaining up to an ±5% error of the expected concentration when tested in buffer and complex media.

A rare case of taper junction corrosion in semi-constrained total knee arthroplasty.

Metallosis is a known yet rare late complication of unicompartmental and total knee arthroplasty (TKA), usually secondary to either metal-backed patellar component failure, mobile-bearing polyethylene dislocation, or catastrophic polyethylene failure and wear through. The majority of literature surrounding metallosis has been published in relation to total hip arthroplasty (THA) metal on metal bearing wear or mechanically assisted crevice corrosion.This case report describes the development of metallosis in a 77-year-old male patient with advanced (Kellgren-Lawrence Grade 4) osteoarthritis with associated valgus deformity, who underwent index TKA with a semiconstrained revision knee system due to intraoperative medial collateral ligament laxity. The taper junction between the titanium alloy stem and cobalt chromium femoral component was the source of diffuse intra-articular metallosis.

Controlling the Collision Type and Frequency of Single Pt Nanoparticles at Chemically Modified Gold Electrodes.

Studying the electrochemical response of single nanoparticles at an electrode surface gives insight into the dynamic and stochastic processes that occur at the electrode interface. Herein, we investigated single platinum nanoparticle collision dynamics and type (elastic vs inelastic) at gold electrode surfaces modified with self-assembled monolayers (SAMs) of varying terminal chemistries. Collision events are measured via the faradaic current from catalytic reactions at the Pt surface. By changing the terminal, solution-facing group of a thiolate monolayer, we observed the effect of hydrophobicity at the solution-electrode interface on single-particle collisions by employing either a hydrophobic -CH3 terminal group (1-hexanethiol), a hydrophilic -OH terminal group (6-mercaptohexanol), or an equimolar mixture of the two. Changes in the terminal group lead to alterations in collision-induced current magnitude, collisional frequency, and the distinct shape of the collision event current transient. The effects of the terminal group of the SAM were probed by measuring quantitative differences in the events monitored through both the hydrogen evolution reaction (HER) and hydrazine oxidation. In both cases, a platinum nanoparticle (PtNP) favors adsorption to bare and hydrophilic surfaces but demonstrates elastic collision behavior when it collides with a hydrophobic surface. In the case of a mixed monolayer, distinct characteristics of hydrophobic and hydrophilic surfaces are observed. We report how single nanoparticle collisions can reveal nanoscale surface heterogeneity and can be used to manipulate the nature of single-particle interactions on an electrode surface by functionalized self-assembled monolayers.

Tuning the Probe-Bilayer Architecture of Silver Nanoneedle-based Ion Channel Probes.

Ion channel probes, as one of the ion channel platforms, provide an appealing opportunity to perform localized detection with a high precision level. These probes come basically in two classes: glass and metal. While the glass-based probes showed the potential to be employed for molecular sensing and chemical imaging, these probes still suffer from limited resolution and lack of control over protein insertion. On the other hand, metal-based nanoneedle probes (gold and silver) have been recently developed to allow reducing probe dimensions to the nanoscale geometry. More specifically, silver probes are preferable owing to their ability to mitigate the channel current decay observed with gold probes and provide a stable DC channel current. However, there are still some challenges related to the probe design and bilayer curvature that render such probes insensitive to small changes in the tip-substrate distance. Herein, we introduce two main pathways to control the probe-bilayer architecture; the first is by altering the probe shape and geometry during the fabrication process of silver probes. The second pathway is by altering the surface characteristics of the silver probe via an electrophoretic deposition process. Our findings reveal that varying the electrochemical etching parameters results in different probe geometries and producing sharper tips with a 2-fold diameter reduction. In addition, the electrophoretic deposition of a cathodic paint on the silver nanoneedle surface led to a miniaturized exposed silver tip that enables the formation of a confined bilayer. We further investigated the characteristics of bilayers supported on both the sharper nanoneedles and the HSR-coated silver probes produced by controlling the etching conditions and electrodeposition process, respectively. We believe this work paves the way to rationally design silver nanoneedle ion channel probes, which are well suited for localized molecular sensing and chemical imaging.

Hip, knee, and shoulder arthroplasty in patients with a history of solid organ transplant: A review.

Solid organ transplants (SOT) have evolved into life-saving interventions for end-stage diseases affecting vital organs. Advances in transplantation techniques, donor selection, and immunosuppressive therapies have enhanced outcomes, leading to a growing demand for SOT. Patients with a solid organ transplant are living long enough to develop the same pathologies which are indicated for joint replacement surgery in the general population. SOT patients who undergo a total hip, knee, or shoulder arthroplasty do similarly in the context of clinical outcomes and implant survival when compared to the general population. These immunosuppressed patients tend to have higher complication rates in the short-term following surgery. Prudent management of these patients in the short-term may be necessary, but patients can expect to do well otherwise.

promSEMBLE: Hard Pattern Mining and Ensemble Learning for Detecting DNA Promoter Sequences.

Accurate identification of DNA promoter sequences is of crucial importance in unraveling the underlying mechanisms that regulate gene transcription. Initiation of transcription is controlled through regulatory transcription factors binding to promoter core regions in the DNA sequence. Detection of promoter regions is necessary if we are to build genetic regulatory networks for biomedical and clinical applications, and for identification of rarely expressed genes. We propose a novel ensemble learning technique using deep recurrent neural networks with convolutional feature extraction and hard negative pattern mining to detect several types of promoter sequences, including promoter sequences with the TATA-box and without the TATA-box, within DNA sequences of four different species. Using extensive independent tests and previously published results, we demonstrate that our method sets a new state-of-the-art of over 98% Matthews correlation coefficient in all eight organism categories for recognizing the stretch of base pairs that code for the promoter region within DNA sequences.

Microscale, Electrochemical, Aptamer-Based Sensors for Enhanced Small-Molecule Detection at Millisecond Time Scales.

Microscale electrodes offer the advantages of increased mass transport rates, high sensitivity, and rapid measurement capabilities. Fabricating electrochemical aptamer-based (E-AB) sensors on these electrode platforms opens new applications to chemical and biological sensing but has remained challenging due to low signal-to-noise ratios and monolayer instability. In this article, we report the development and characterization of E-AB sensors on a gold microelectrode platform (∼500 nm radius). To overcome the small current response, we modified the electrodes by growing nanostructures via electrodeposition. We interrogated the sensors with two different electroanalytical techniques, square wave voltammetry (SWV) and intermittent pulse voltammetry (IPA), to measure the representative response of an ATP sensor and determine aptamer-target binding and dissociation time scales. We find robust and stable sensor performance with an increased response rate over sensors fabricated on macroscale electrodes. These results demonstrate that sensors developed on this microelectrode platform can be employed for enhanced spatiotemporal resolution measurements in chemical and biological environments.

Perspective-Assessing Electrochemical, Aptamer-Based Sensors for Dynamic Monitoring of Cellular Signaling.

Electrochemical, aptamer-based (E-AB) sensors provide a generalizable strategy to quantitatively detect a variety of targets including small molecules and proteins. The key signaling attributes of E-AB sensors (sensitivity, selectivity, specificity, and reagentless and dynamic sensing ability) make them well suited to monitor dynamic processes in complex environments. A key bioanalytical challenge that could benefit from the detection capabilities of E-AB sensors is that of cell signaling, which involves the release of molecular messengers into the extracellular space. Here, we provide a perspective on why E-AB sensors are suited for this measurement, sensor requirements, and pioneering examples of cellular signaling measurements.

DrugMap: A quantitative pan-cancer analysis of cysteine ligandability.

Cysteine-focused chemical proteomic platforms have accelerated the clinical development of covalent inhibitors of a wide-range of targets in cancer. However, how different oncogenic contexts influence cysteine targeting remains unknown. To address this question, we have developed DrugMap , an atlas of cysteine ligandability compiled across 416 cancer cell lines. We unexpectedly find that cysteine ligandability varies across cancer cell lines, and we attribute this to differences in cellular redox states, protein conformational changes, and genetic mutations. Leveraging these findings, we identify actionable cysteines in NFκB1 and SOX10 and develop corresponding covalent ligands that block the activity of these transcription factors. We demonstrate that the NFκB1 probe blocks DNA binding, whereas the SOX10 ligand increases SOX10-SOX10 interactions and disrupts melanoma transcriptional signaling. Our findings reveal heterogeneity in cysteine ligandability across cancers, pinpoint cell-intrinsic features driving cysteine targeting, and illustrate the use of covalent probes to disrupt oncogenic transcription factor activity.

Development of an Electrochemical, Aptamer-Based Sensor for Dynamic Detection of Neuropeptide Y.

The ability to monitor dynamic changes in neuropeptide Y (NPY) levels in complex environments can have an impact on many fields, including neuroscience and immunology. Here, we describe the development of an electrochemical, aptamer-based (E-AB) sensor for the dynamic (reversible) measurement of physiologically relevant (nanomolar) concentrations of neuropeptide Y. The E-AB sensors are fabricated using a previously described 80 nucleotide aptamer1 reported to specifically bind NPY with a binding affinity Kd = 0.3 ± 0.2 uM. We investigated two redox tag placement locations on the aptamer sequence (terminal vs internal) and various sensor fabrication and interrogation parameters to tune the performance of the resulting sensor. The best-performing sensor architecture displayed a physiologically relevant dynamic range (nM) and low limit of detection and is selective among competitors and similar molecules. The development of this sensor accomplishes two breakthroughs: first, the development of a nonmicrofluidic aptamer-based electrochemical sensor that can detect NPY on a physiologically relevant (seconds to minutes) time scale and across a relevant concentration range; second, the expansion of the range of molecules for which an electrochemical, aptamer-based sensor can be used.

Code status orders in hospitalized patients with COVID-19.

Background: The COVID-19 pandemic created complex challenges regarding the timing and appropriateness of do-not-attempt cardiopulmonary resuscitation (DNACPR) and/or Do Not Intubate (DNI) code status orders. This paper sought to determine differences in utilization of DNACPR and/or DNI orders during different time periods of the COVID-19 pandemic, including prevalence, predictors, timing, and outcomes associated with having a documented DNACPR and/or DNI order in hospitalized patients with COVID-19. Methods: A cohort study of hospitalized patients with COVID-19 at two hospitals located in the Midwest. DNACPR code status orders including, DNI orders, demographics, labs, COVID-19 treatments, clinical interventions during hospitalization, and outcome measures including mortality, discharge disposition, and hospice utilization were collected. Patients were divided into two time periods (early and late) by timing of hospitalization during the first wave of the pandemic (March-October 2020). Results: Among 1375 hospitalized patients with COVID-19, 19% (n = 258) of all patients had a documented DNACPR and/or DNI order. In multivariable analysis, age (older) p =< 0.01, OR 1.12 and hospitalization early in the pandemic p = 0.01, OR 2.08, were associated with having a DNACPR order. Median day from DNACPR order to death varied between cohorts p => 0.01 (early cohort 5 days versus late cohort 2 days). In-hospital mortality did not differ between cohorts among patients with DNACPR orders, p = 0.80. Conclusions: There was a higher prevalence of DNACPR and/or DNI orders and these orders were written earlier in the hospital course for patients hospitalized early in the pandemic versus later despite similarities in clinical characteristics and medical interventions. Changes in clinical care between cohorts may be due to fear of resource shortages and changes in knowledge about COVID-19.

Examining the Influence of Physician Assistant/Associate Scope of Practice Reforms and Individual Characteristics on Wages.

High labor demand for physician assistants/associates (PA) has led to substantial PA workforce and wage growth. During this growth period, states have adopted reforms to reduce PA scope of practice restrictions and reports of significant gender and race wage disparities have emerged. This study examined data from the American Community Survey to investigate the influence of demographic characteristics, human capital, and scope of practice reforms on PA wages from 2008 to 2017. Using an ordinary least squares two-way fixed effects estimator, a significant association between reforms and PA wages could not be established. Rather, wages were found to be strongly associated with human capital and demographic characteristics. Gender and race wage disparities persist, with female PAs earning 7.5% lower wages than male PAs and White PAs earning 9.1% to 14.5% higher wages than racial and ethnic minority PAs. These findings suggest a minimal influence of prior scope of practice reforms on PA wages.

Week-Long Operation of Electrochemical Aptamer Sensors: New Insights into Self-Assembled Monolayer Degradation Mechanisms and Solutions for Stability in Serum at Body Temperature.

Conventional wisdom suggests that widely utilized self-assembled alkylthiolate monolayers on gold are too unstable to last more than several days when exposed to complex fluids such as raw serum at body temperature. Demonstrated here is that these monolayers can not only last at least 1 week under such harsh conditions but that significant applied value can be captured for continuous electrochemical aptamer biosensors. Electrochemical aptamer biosensors provide an ideal tool to investigate monolayer degradation, as aptamer sensors require a tightly packed monolayer to preserve sensor signal vs background current and readily reveal fouling by albumin and other solutes when operating in biofluids. Week-long operation in serum at 37 °C is achieved by (1) increasing van der Waals interactions between adjacent monolayer molecules to increase the activation energy required for desorption, (2) optimizing electrochemical measurement to decrease both alkylthiolate oxidation and electric-field-induced desorption, and (3) mitigating fouling using protective zwitterionic membranes and zwitterion-based blocking layers with antifouling properties. This work further proposes origins and mechanisms of monolayer degradation in a logical stepwise manner that was previously unobservable over multiday time scales. Several of the observed results are surprising, revealing that short-term improvements to sensor longevity (i.e., hours) actually increase sensor degradation in the longer term (i.e., days). The results and underlying insights on mechanisms not only push forward fundamental understanding of stability for self-assembled monolayers but also demonstrate an important milestone for continuous electrochemical aptamer biosensors.