Faculty Bibliography

The period following basic training is a challenging one for young service members. They are away from family, training intensely for their future career fields, and may be navigating long distance relationships with intimate partners for the first time. Relationship problems are common and can significantly undermine adjustment and training. This study assessed an array of possible risk markers among partnered service members (SMs) as they arrived at technical training in the Department of the Air Force, along with a variety of relationship outcomes, and followed them (and some of their partners) for the subsequent 24 months. We then used Binary Classification and Regression Trees (CART) analysis to identify the optimal subset of predictor items and cut points to screen prospectively for negative relationship outcomes (i.e. significant relationship distress, relationship dissolution, occurrence of infidelity or intimate partner violence) at any follow-up assessment. We identified a 14-item screener that differentiated low risk (i.e. 32-42% chance of negative outcome) from moderate risk (68-70% chance of negative outcome) and high risk (88% chance of negative outcome) SMs, as well as differentiating low-to-moderate risk from high-risk SMs. This scoring flexibility allows the screening threshold to be matched to diverse programmatic goals, balancing the cost of potential prevention efforts against the level of risk. Early identification of at risk SMs will enable targeted prevention efforts.

Dietary protein is a key regulator of metabolic health in humans and rodents. Many of the benefits of protein restriction are mediated by reduced intake of dietary branched-chain amino acids (leucine, valine and isoleucine) and restriction of the branched-chain amino acids is sufficient to extend healthspan and lifespan in mice. Here we find that valine restriction (Val-R) improves metabolic health in C57BL/6J mice, promotes leanness and glycemic control across ages, and reduces frailty, cancer prevalence and senescent cell burden in both sexes while increasing median male lifespan by 23%. Assessing gene relationships across tissues, we identified a liver gene module enriched in mitochondrial pathways and increased mitochondrial respiration in Val-R-fed male mice. Our results demonstrate that Val-R improves multiple aspects of healthspan in mice of both sexes, extends lifespan in male mice and suggests that interventions that mimic Val-R may have translational potential for aging and age-related diseases.

BACKGROUND:In situ simulation (ISS) has seen broad use in academic emergency medicine (EM). Studies with limited clinical data suggest a dual paradigm model to assess the efficacy of these educational activities based on their impact on both ongoing and future quality of care. We conducted a retrospective cohort study to assess the impact of government-mandated mass casualty incident (MCI) ISS drills on ongoing department operations and quality clinical care. METHODS:We conducted a retrospective study of patients presenting to an adult tertiary academic emergency department during scheduled and unscheduled ISS MCI drills. We assessed the impact of ISS on operational and triage metrics by comparing scheduled and unscheduled drills. RESULTS:Being treated during an ongoing MCI ISS, in both the scheduled and unscheduled simulation formats, was associated with a higher average door to triage times (20.6 min in the MCI ISS cohort vs 15.8 min in the control cohort; p<0.005) and lower Canadian Triage and Acuity Scale (CTAS) scores (CTAS 1 and 2: 0.8% and 14.5% in the MCI ISS cohort vs 1.6% and 17.1% in the control cohort, p<0.025). Secondary analysis, evaluating differences between case and control cohorts in distinct scheduled and unscheduled ISS subgroups, showed that unscheduled but not scheduled ISS were associated with higher average door to triage times (29.0 min in the unscheduled MCI ISS case cohort vs 21.2 min in the unscheduled MCI ISS control cohort; p<0.001) and lower CTAS acuity scores (CTAS 1 and 2: 0.0% and 17.9% in the unscheduled MCI ISS cohort vs 2.8% and 27.9% in the unscheduled MCI ISS control cohort; p<0.001). CONCLUSION/CONCLUSIONS:In this study, there was a significant association between increased door to triage time and lower acuity triage score designation for patients treated during an ongoing MCI ISS education drill. Secondary analysis demonstrated that these findings were only observed during unscheduled simulations, suggesting that the effects may be modifiable.

BACKGROUND:Dental caries remains one of the most prevalent noncommunicable diseases worldwide despite decades of clinical and behavioural interventions. Persistently high prevalence suggests that current approaches are better organised for ongoing disease management than for preventing new disease occurrence. This commentary examines whether an elimination framework could provide a more coherent and outcome-oriented direction for oral health policy and practice. METHODOLOGY/METHODS:We apply the Dahlem Framework to assess whether dental caries meets established criteria for disease eradication. We then position caries within the classical continuum of control, elimination, and eradication, drawing on current evidence on caries aetiology, fluoride exposure, dietary environments, primary care integration, surveillance, and the social and commercial determinants of oral health. RESULTS:Dental caries does not meet the criteria for eradication. It has no single causal agent, no interruptible transmission cycle, no immunising intervention, and no global surveillance architecture capable of detecting incidence. Eradication is therefore conceptually impossible. Elimination, however, defined as the stable disappearance of dental caries as a public health problem within a defined population, is biologically plausible and operationally achievable. An elimination frame shifts expectations from managing recurrence to preventing occurrence and reframes caries as a system outcome rather than solely an individual behavioural or clinical problem. CONCLUSION/CONCLUSIONS:Caries elimination is not the promise of biological absence, but a realistic and measurable population health objective. Adopting an elimination framework could strengthen policy coherence, surveillance, implementation research, professional education, and accountability, while reorienting oral health systems toward prevention, equity, and sustained population-level impact.

Many research questions-particularly those in environmental health-do not involve binary exposures. In environmental epidemiology, this includes multivariate exposure mixtures with nondiscrete components. Causal inference estimands and estimators to quantify the relationship between an exposure mixture and an outcome are relatively few. We propose an approach to quantify a relationship between a shift in the exposure mixture and the outcome-either in a single timepoint or longitudinal setting. The shift in the exposure mixture can be defined flexibly in terms of shifting one or more components, including examining the interaction between mixture components, and in terms of shifting the same or different amounts across components. The estimand we discuss has a similar interpretation as a main effect regression coefficient. First, we focus on choosing a shift in the exposure mixture supported by observed data. We demonstrate how to assess extrapolation and modify the shift to minimize reliance on extrapolation. Second, we propose estimating the relationship between the exposure mixture shift and outcome completely nonparametrically, using machine learning in model fitting. This is in contrast to other common approaches, which employ parametric modeling for at least some relationships, which we would like to avoid because parametric modeling assumptions in complex, nonrandomized settings are tenuous at best. We are motivated by longitudinal data on pesticide exposures among participants in the Center for the Health Assessment of Mothers and Children of Salinas Maternal Cognition cohort. We examine the relationship between longitudinal exposure to agricultural pesticides and risk of hypertension. We provide step-by-step code to facilitate the easy replication and adaptation of the proposed approach.

INTRODUCTION/BACKGROUND:Traumatic dental injuries (TDIs) require prompt and accurate guidance, yet little is known about how the prompting influences the quality of artificial intelligence (AI) chatbot responses in these situations. METHODS:Four dental trauma scenarios were developed by expert endodontists. For each scenario, a series of questions was posed to 4 AI chatbots (Claude Sonnet 3.5, Microsoft Copilot, GPT-4, Gemini Pro 2.5) using 2 approaches: unprompted layperson phrasing (n = 10) and endodontist's prompts referencing International Association of Dental Traumatology guidelines (n = 10). Responses were independently evaluated by 2 raters for validity, completeness, and relevance using a 5-point ordinal scale. RESULTS:Scores (n = 1920) of responses to endodontist questions were associated with significantly higher odds of receiving superior ratings across all 3 domains: validity (odds ratio [OR] = 1.82; 95% confidence interval [CI]: 1.35-2.38; P < .001); completeness (OR = 2.50; 95% CI: 1.85-3.33; P < .001) and relevance (OR = 2.94; 95% CI: 2.04-4.17; P < .001). When a threshold-based acceptability (score ≥4) was applied, responses to endodontist queries were more often acceptable in criterion-based as well as overall analyses (P < .05). CONCLUSIONS:The quality of AI chatbot guidance in TDIs is significantly associated with how questions are asked. While clinically structured prompts yield more reliable responses, most patients facing dental trauma are unlikely to formulate questions in this way. This gap highlights an important limitation of current AI chatbot applications in TDIs and underscores the need for caution when relying on these tools without professional input.

G protein-coupled receptors (GPCRs) and TRPV (transient receptor potential vanilloid) channels are crucial for signal transduction in physiological processes, including neurotransmission, pain, and itch. Downstream effectors of GPCR signaling can directly stimulate TRPV channels or enhance their sensitivity to stimuli, a process known as TRPV sensitization. Traditionally, GPCRs are activated at the cell surface by extracellular agonists, triggering signaling cascades. Recent evidence suggests GPCRs continue to signal from intracellular organelles. The human Mas-related G-protein coupled receptor X1 (MrGPRX1) is a GPCR expressed in primary sensory neurons involved in nociception and pruritus. Recent studies demonstrated how intracellular GPCR signaling regulates neuronal activity. However, there is no evidence characterizing MrGPRX1 trafficking or intracellular signaling. Herein, we characterized MrGPRX1 signaling within the endosomal network and its role in sensitizing TRPV1 channels to enhance itch signaling. Utilizing subcellular targeted biosensors, we demonstrated MrGPRX1 can traffic and signal from endosomes. Immunofluorescence analysis showed that MrGPRX1 internalizes following BAM8-22 stimulation. BRET assays revealed that MrGPRX1 activation induces Gα

Conductive hydrogels have emerged as promising materials for soft tissue interfacing by combining tissue-like mechanical compliance with electrical conductivity, thereby enabling improved electrical communication with electroactive biological tissues. This work presents an electroconductive composite hydrogel fabricated via light-based vat-polymerization by integrating a choline-based bio-ionic liquid (IL) with gelatin methacryloyl (GelMA). The resulting hydrogels demonstrate tunable conductivity, structural integrity, and high print fidelity when fabricated using digital light processing (DLP) light-based 3D printing. Electrical conductivity was optimized at 20% v/v IL concentration, with the hydrogels demonstrating stable performance for over 28 days. A food-grade photoabsorber was integrated into the formulation to improve DLP resolution and was effectively removed after printing process. The hydrogels supported the human mesenchymal stem cells' viability and proliferation, confirming their cytocompatibility. They also promoted enhanced maturation of primary neurons, demonstrating a supportive microenvironment for neural cells. In vivo implantation of indocyanine green-loaded hydrogels exhibited sustained stability and robust retention of signal over a period of 4 weeks, with histological analysis indicating seamless integration with surrounding tissues. Impedance spectroscopy at both gut and spinal cord interfaces illustrated that GelMA/IL composites achieved the lowest impedance across a range of frequencies, outperforming both GelMA-only and tissue-only conditions. Collectively, these findings position light-based vat-polymerized electroconductive composites as a promising platform for the development of anatomically conformal materials tailored for soft tissue interfacing.

This study evaluated the effects of glass infiltration and hydrothermal aging on the microstructural and optical properties of minimally processed recycled 3Y-TZP. Unprocessed 3Y-TZP remnants were milled into powder, compacted into discs, and sintered. Specimens were divided into six groups according to glass infiltration and hydrothermal aging (immediate, 50 h, and 100 h at 134 °C/2.2 bar). Particle size was measured by laser diffraction. Density and optical properties (contrast ratio and translucency) were longitudinally evaluated on the same specimens using Archimedes' principle and reflectance measurements (n = 10), whereas crystalline phases (Raman spectroscopy, n = 3), surface and cross-sectional morphology (n = 3), and elemental composition (n = 3) were analyzed on independent specimens allocated to each experimental condition. Color stability and translucency variation were compared with perceptibility (PT = 0.81; TPT = 0.62) and acceptability (AT = 1.77; TAT = 2.62) thresholds (n = 10). Density data were analyzed using one-way repeated-measures ANOVA, while optical properties were analyzed using two-way repeated-measures ANOVA, followed by Tukey's post hoc test. Mean particle size of recycled powder was 1.61 μm. Relative densities for immediate, 50 h, and 100 h groups were 99.68%, 99.24%, and 99.04%. Raman spectra revealed predominance of tetragonal-cubic phases in immediate non-infiltrated group, while monoclinic phase prevailed in others. SEM showed homogeneous surfaces. EDS confirmed zirconium, yttrium, and hafnium in non-infiltrated groups, and silicon, aluminum, sodium, potassium, and calcium in infiltrated. Non-infiltrated groups showed lower contrast ratio and greater translucency than infiltrated, independent of aging. Aging minimally affected optical properties, except infiltrated specimens, where translucency was higher immediately than after 50-100 h. All groups exhibited color and translucency variation below perceptibility and acceptability thresholds. Prolonged hydrothermal degradation influenced the microstructural and optical features of recycled 3Y-TZP, while glass infiltration further modified these characteristics, reducing translucency while increasing opacity and color stability.

BACKGROUND AND OBJECTIVES/OBJECTIVE:The objective of this study was to compare sociodemographic factors, presenting characteristics, and outcomes between cohorts of patients receiving surgery for spinal metastases at 2 neighboring institutions, 1 private and 1 public, affiliated with a single major academic medical center in a large metropolitan area. METHODS:This analysis included all patients who underwent decompressive surgery for extradural spinal metastases. Sociodemographic factors, treatment characteristics, and outcomes were compared between those treated at a private hospital and a neighboring public hospital using Rao-Scott χ 2 tests for categorical variables, Student t tests for continuous variables, and the Kaplan-Meier product-limit method for overall survival and progression-free survival. RESULTS:Compared with those treated at our private hospital, patients treated at our public hospital were more often younger ( P = .005), of Black or Hispanic race (72.6% vs 19%, P < .001), and uninsured (16% vs 5.6%, P = .005). They more frequently presented with epidural spinal cord compression grade 3 (76% vs 56.8%, P = .027), were nonambulatory before surgery (56.9% vs 13.5%, P < .001), and had increased neurological impairment as denoted by American Spinal Injury Association Impairment Scale grades of A, B, or C (39.2% vs 7.5%). Patients treated at our public hospital had shorter median follow-up time (92 vs 302.5 days, P = .004). Multivariate analysis did not reveal a significant difference in overall survival or progression-free survival between hospitals, instead demonstrating associations with primary tumor histology and number of spinal metastases ( P < .05). CONCLUSION/CONCLUSIONS:There were substantial disparities in sociodemographic factors, presenting local disease burden, and postoperative neurological outcome but no difference in survival outcome, between patients treated at our public and private hospitals. These findings underscore the need for more equitable screening, surveillance, and referral structures.