Background:Despite the effects of prosthetic foot mechanical properties on gait of people with lower limb amputation, scant forefoot and heel stiffness data exist to help guide prosthetic foot prescription.Objective:To measure forefoot and heel linear stiffness properties across commonly prescribed commercial prosthetic foot models and to describe variations in stiffness across feet targeted for users with different body weights and foot sizes.Study design:Mechanical testing of five types of commercial prosthetic feet across nine user body weight and foot size combinations.Methods:Linear forefoot and heel stiffness (force vs. displacement) data were collected for 41 prosthetic feet. Quasistatic testing was conducted at −15 and +20 degrees to isolate loading of the heel and forefoot, respectively.Results:Overall, there was a significant relationship between user body weight and both forefoot and heel stiffness, when adjusted for foot size and type (P < 0.001). However, there were a substantial number of inconsistencies across foot type within example user body weight and foot sizes combination. Furthermore, the relative order of forefoot stiffness across foot type differed from the relative order of heel stiffness across foot type.Conclusions:The inconsistencies and differences in relative order of forefoot and heel stiffness across commercial foot type suggest the importance of publishing objective stiffness and other mechanical properties of prosthetic feet. These data can aid clinicians in better matching mechanical properties of prosthetic feet with the functional goals and abilities of prosthesis users.

Streptococcus mutans is a commensal of the human oral microbiome that can promote dental caries under conditions of dysbiosis. This study investigates metalloregulators and their involvement in the S. mutans oxidative stress response. Oxidative stress in the human mouth can derive from temporal increases in reactive oxygen species (ROS) after meal consumption and from endogenous bacterial ROS-producers that colonize the dentition. We hypothesize that the S. mutans PerR (SMU.593) and SloR (SMU.186) metalloregulatory proteins contribute to the regulation of oxidative stress genes and their products. Expression assays with S. mutans UA159 wild type cultures exposed to H2O2 reveal that H2O2 upregulates perR, and that PerR represses sloR transcription upon binding directly to Fur and PerR consensus sequences within the sloR operator. In addition, the results of Western blot experiments implicate the Clp proteolytic system in SloR degradation under conditions of H2O2-stress. To reveal a potential role for SloR in the H2O2-resistant phenotype of S. mutans GMS802 (a perR-deficient strain), we generated a sloR/perR double knockout mutant, GMS1386, where we observed upregulation of the tpx and dpr antioxidant genes. These results are consistent with GMS802 H2O2 resistance and with a role for PerR as a transcriptional repressor. Cumulatively, these findings support a reciprocal relationship between PerR and SloR during the S. mutans oxidative stress response and begin to elucidate the fitness strategies that evolved to foster S. mutans persistence in the transient environments of the human oral cavity. IMPORTANCE In 2020, untreated dental caries, especially in the permanent dentition, ranked among the most prevalent infectious diseases worldwide, disproportionately impacting individuals of low socioeconomic status. Untreated caries can lead to systemic health problems and has been associated with extended school and work absences, inappropriate use of emergency departments, and an inability for military forces to deploy. Together with public health policy, research aimed at alleviating S. mutans-induced tooth decay is important because it can improve oral health (and overall health), especially in underserved populations. This research, focused on S. mutans metalloregulatory proteins and their gene targets, is significant because it can promote virulence gene control in an important oral pathogen, and contribute to the development of an anti-caries therapeutic that can reduce tooth decay.

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BackgroundSelection of a foot is an important aspect of prosthetic prescription and vital to maximizing mobility and functional goals after lower limb amputation. Development of a standardized approach to soliciting user experiential preferences is needed to improve evaluation and comparison of prosthetic feet.ObjectiveTo develop rating scales to assess prosthetic foot preference and to evaluate use of these scales in people with transtibial amputation after trialing different prosthetic feet.DesignParticipant‐blinded, repeated measures crossover trial.SettingVeterans Affairs and Department of Defense Medical Centers, laboratory setting.ParticipantsSeventy‐two male prosthesis users with unilateral transtibial amputation started, and 68 participants completed this study.InterventionsParticipants trialed three mobility‐level appropriate commercial prosthetic feet briefly in the laboratory.Main Outcome Measures“Activity‐specific” rating scales were developed to assess participants' ability with a given prosthetic foot to perform typical mobility activities (eg, walking at different speeds, on inclines, and stairs) and “global” scales to rate overall perceived energy required to walk, satisfaction, and willingness to regularly use the prosthetic foot. Foot preference was determined by comparing the rating scale scores, after laboratory testing.ResultsThe greatest within‐participant differences in scores among feet were observed in the “incline” activity, where 57% ± 6% of participants reported 2+ point differences. There was a significant association (p < .05) between all “activity‐specific” rating scores (except standing) and each “global” rating score.ConclusionsThe standardized rating scales developed in this study could be used to assess prosthetic foot preference in both the research and clinical settings to guide prosthetic foot prescription for people with lower limb amputation capable of a range of mobility levels.

Research suggests that increased voting among adults is associated with improved child health. Despite the benefits of voting, the United States has low voter turnout compared with peer nations. Turnout is especially low among marginalized people in the United States. Voter registration is essential for increasing voter turnout, and registration efforts have been successfully carried out in clinical settings. Working with a nonprofit called Vot-ER, we advocated for nonpartisan voter registration efforts in pediatric settings nationwide preceding the November 2020 US elections. We describe lessons learned from these efforts. Using data obtained from Vot-ER, we also provide the first estimates of participation in a national voter registration campaign in pediatric settings. There was widespread engagement in voter registration efforts among pediatricians in 2020. Many lessons were learned from these efforts, including the benefits of advanced planning because registration deadlines can be up to 1 month in advance of Election Day. Obtaining buy-in from numerous stakeholders (e.g., health center leadership, public relations teams) supports widespread staff participation. Also important is to consider the tradeoffs between active voter registration (in which staff can broach the topic of voting with patients and families) and passive efforts (in which voting is discussed only if patients or families inquire about it). These and other lessons can inform future voter registration efforts in diverse pediatric settings across the country.