Signaling dynamics distinguish high- and low-priority neutrophil chemoattractant receptors.

Human neutrophils respond to multiple chemoattractants to guide their migration from the vasculature to sites of infection and injury, where they clear pathogens and amplify inflammation. To properly focus their responses during this complex navigation, neutrophils prioritize pathogen- and injury-derived signals over long-range inflammatory signals, such as the leukotriene LTB4, secreted by host cells. Different chemoattractants can also drive qualitatively different modes of migration even though their receptors couple to the same Gαi family of G proteins. Here, we used live-cell imaging to demonstrate that the responses differed in their signaling dynamics. Low-priority chemoattractants caused transient responses, whereas responses to high-priority chemoattractants were sustained. We observed this difference in both primary neutrophils and differentiated HL-60 cells, for downstream signaling mediated by Ca2+, a major regulator of secretion, and Cdc42, a primary regulator of polarity and cell steering. The rapid attenuation of Cdc42 activation in response to LTB4 depended on the phosphorylation sites Thr308 and Ser310 in the carboxyl-terminal tail of its receptor LTB4R in a manner independent of endocytosis. Mutation of these residues to alanine impaired chemoattractant prioritization, although it did not affect chemoattractant-dependent differences in migration persistence. Our results indicate that distinct temporal regulation of shared signaling pathways distinguishes between receptors and contributes to chemoattractant prioritization.

Modifications to student quarantine policies in K-12 schools implementing multiple COVID-19 prevention strategies restores in-person education without increasing SARS-CoV-2 transmission risk, January-March 2021.

OBJECTIVE: To determine whether modified K-12 student quarantine policies that allow some students to continue in-person education during their quarantine period increase schoolwide SARS-CoV-2 transmission risk following the increase in cases in winter 2020-2021. METHODS: We conducted a prospective cohort study of COVID-19 cases and close contacts among students and staff (n = 65,621) in 103 Missouri public schools. Participants were offered free, saliva-based RT-PCR testing. The projected number of school-based transmission events among untested close contacts was extrapolated from the percentage of events detected among tested asymptomatic close contacts and summed with the number of detected events for a projected total. An adjusted Cox regression model compared hazard rates of school-based SARS-CoV-2 infections between schools with a modified versus standard quarantine policy. RESULTS: From January-March 2021, a projected 23 (1%) school-based transmission events occurred among 1,636 school close contacts. There was no difference in the adjusted hazard rates of school-based SARS-CoV-2 infections between schools with a modified versus standard quarantine policy (hazard ratio = 1.00; 95% confidence interval: 0.97-1.03). DISCUSSION: School-based SARS-CoV-2 transmission was rare in 103 K-12 schools implementing multiple COVID-19 prevention strategies. Modified student quarantine policies were not associated with increased school incidence of COVID-19. Modifications to student quarantine policies may be a useful strategy for K-12 schools to safely reduce disruptions to in-person education during times of increased COVID-19 community incidence.

Longitudinal relationship between experience of sexual harassment and 2-year body image and weight outcomes in adolescence: mediation through self-objectification and psychological distress.

BACKGROUND: The current study investigated the experience of sexual harassment as a risk factor for weight gain and weight/shape concerns in a community sample of adolescents, with potential mediating factors self-objectification and psychological distress. METHOD: 1034 Australian adolescents (aged 11 to 19 years) from the EveryBODY longitudinal study of disordered eating pathology participated. Data were collected through online surveys annually for 3 years. Participants completed self-report measures of demographics, sexual harassment, psychological distress, self-objectification, weight/shape concerns and BMI percentile. RESULTS: A parallel mediation model adjusting for baseline scores found no direct effect between baseline experiences of sexual harassment and change in BMI percentile or weight/shape concern after 2 years. Experiences of sexual harassment significantly increased self-objectification scores after 1 year in female adolescents. Subsequently, higher self-objectification significantly increased the risk of greater weight/shape concern after 1 year in female adolescents. However, no significant mediating relationship was found in the relationship between sexual harassment and weight/shape concern or BMI percentile for either gender. Psychological distress was found to be a clear risk factor for weight/shape concern in both genders after 1 year. CONCLUSIONS: Intervention programmes in schools should focus on developing policies to reduce sexual harassment, self-objectification and distress in adolescents. LEVEL OF EVIDENCE: Level IV, longitudinal multiple time series without intervention.

Assessing COVID-19 testing strategies in K-12 schools in underserved populations: study protocol for a cluster-randomized trial.

BACKGROUND: Since March 2020, COVID-19 has disproportionately impacted communities of color within the United States. As schools have shifted from virtual to in-person learning, continual guidance is necessary to understand appropriate interventions to prevent SARS-CoV-2 transmission. Weekly testing of students and staff for SARS-CoV-2 within K-12 school setting could provide an additional barrier to school-based transmission, especially within schools unable to implement additional mitigation strategies and/or are in areas of high transmission. This study seeks to understand the role that weekly SARS-CoV-2 testing could play in K-12 schools. In addition, through qualitative interviews and listening sessions, this research hopes to understand community concerns and barriers regarding COVID-19 testing, COVID-19 vaccine, and return to school during the COVID-19 pandemic. METHODS/DESIGN: Sixteen middle and high schools from five school districts have been randomized into one of the following categories: (1) Weekly screening + symptomatic testing or (2) Symptomatic testing only. The primary outcome for this study will be the average of the secondary attack rate of school-based transmission per case. School-based transmission will also be assessed through qualitative contact interviews with positive contacts identified by the school contact tracers. Lastly, new total numbers of weekly cases and contacts within a school-based quarantine will provide guidance on transmission rates. Qualitative focus groups and interviews have been conducted to provide additional understanding to the acceptance of the intervention and barriers faced by the community regarding SARS-CoV-2 testing and vaccination. DISCUSSION: This study will provide greater understanding of the benefit that weekly screening testing can provide in reducing SARS-CoV-2 transmission within K-12 schools. Close collaboration with community partners and school districts will be necessary for the success of this and similar studies. TRIAL REGISTRATION: NCT04875520 . Registered May 6, 2021.

Conversion of a Skilled Nursing and Rehabilitation Facility into a Satellite Hospital in Response to a COVID-19 Surge.

BACKGROUND: New York City was among the earliest and hardest hit areas during the COVID-19 pandemic. Prior to the peak of the surge in April 2020, a makeshift hospital was opened to address the growing need of overflow beds in Brooklyn, New York. A rehabilitation center was converted into a satellite hospital with a capacity of up to 425 patient beds in 10 days. DESIGN-BUILD APPROACH: Our institution worked in coordination with larger hospital systems and state and local governments, which allowed for a rapid lease of an underutilized structure, influx of supplies, and personnel. Hospital staff were voluntarily redeployed from their assigned services based on reduced need. OUTCOMES: A total of 204 COVID-19 patients were accepted for transfer to the facility between April 6, 2020, and May 11, 2020. There were no major adverse outcomes and no deaths at the facility. LESSONS LEARNED: When a surge of patients is projected to outnumber the available beds in a hospital, such as during a pandemic, it may become necessary to establish a satellite facility. Creativity with existing spaces, health care infrastructure, and reallocation of available resources, as well as having all stakeholders on board, is imperative. Providing mandatory emergency planning and response trainings to hospital staff and leadership can improve preparedness. By leaning on revised protocols established at the satellite facility during the initial surge, the hospital was able to lease and convert another nursing facility and make it patient-ready in less than one week during the second surge of COVID-19 patients.

Understanding the relationship between sexual harassment and eating disorder psychopathology: A systematic review and meta-analysis.

OBJECTIVE: The experience of sexual harassment (SH) may exacerbate the drive toward an ideal and often unattainable physical appearance, creating the foundation of unhealthy eating, and greater shape and weight concerns. This systematic review aimed to synthesize evidence on the relationship between SH and eating disorder psychopathology, as well as mediating and moderating factors that contribute to this relationship. METHOD: Six key databases were searched from inception to August 2020; including CINAHL, PsycInfo, PubMed, Medline, Scopus, and Web of Science. RESULTS: Overall, 15 studies meeting inclusion criteria were found, with 14 reporting a statistically significant relationship between SH and eating disorder psychopathology. A meta-analysis with 12 cross-sectional studies confirmed a small but significant effect for this concurrent association. Moderators of this relationship included gender, posttraumatic stress, and anxiety. No studies in this review conducted true mediation. DISCUSSION: Conclusions about causal and mediating relationship between SH and eating disorder psychopathology are constrained by the preponderance of cross-sectional design (14 of the 15 studies). Therefore, it is recommended that future studies focus on the use of longitudinal design, and also on adolescent populations, where first experiences of SH are usually reported, and which is also the peak age of onset for eating disorders.

OBJETIVO: La experiencia del acoso sexual puede exacerbar el impulso hacia una apariencia física ideal y a menudo inalcanzable, creando la base de una alimentación poco saludable, y mayores preocupaciones con la figura y peso corporal. Esta revisión sistemática tuvo como objetivo sintetizar la evidencia sobre la relación entre el acoso sexual y la psicopatología del trastorno alimentario, así como mediar y moderar los factores que contribuyen a esta relación. MÉTODO: Se buscó en seis bases de datos clave, desde el inicio hasta agosto de 2020; incluyendo CINAHL, PsycInfo, PubMed, Medline, Scopus, Web of Science. RESULTADOS: En total, se encontraron 15 estudios que cumplían con los criterios de inclusión, y 14 reportaron una relación estadísticamente significativa entre el acoso sexual y la psicopatología de trastornos de la conducta alimentaria. Un metanálisis con 12 estudios transversales confirmó un pequeño pero significativo efecto para esta asociación simultánea. Los moderadores de esta relación incluyeron género, estrés postraumático y ansiedad. Ningún estudio en esta revisión llevó a cabo una verdadera mediación. DISCUSIÓN: Las conclusiones sobre la relación causal y mediadora entre el acoso sexual y la psicopatología de los trastornos de la conducta alimentaria están limitadas por la preponderancia del diseño transversal (14 de los 15 estudios). Por lo tanto, se recomienda que los futuros estudios se centren en el uso del diseño longitudinal, y también en las poblaciones adolescentes, donde por lo general se reportan las primeras experiencias de acoso sexual, y que también son la edad pico de inicio para los trastornos de la conducta alimentaria.

Enabling Biomimetic Place-Based Design at Scale.

Amidst the inter-related challenges of climate change, resource scarcity, and population growth, the built environment must be designed in a way that recognises its role in shaping and being shaped by complex social and ecological systems. This includes avoiding the degradation of living systems in the design and construction of buildings and infrastructure, as well as enhancing the built environment's resilience to disturbance by those systems. This paper explores the potential for biomimetic place-based design (BPD) to inform resilient and regenerative built environment outcomes by learning from local ecosystems. One recognised hurdle is the upfront resourcing required to establish the biomimetic knowledge base for each project. However, conducting BPD projects at-scale (i.e., city or region) can improve the method's value-proposition by better leveraging upfront research efforts, design concepts, and strategies. This research identifies existing barriers to the widespread adoption of BPD and presents an action framework for capability-building across industry, government, and academia to enable application at-scale. Drawing on findings from workshops in the USA and Australia, it creates a resource for colleagues looking to apply BPD in a city or region and offers next steps for research and development.

Findings of Case-Study Analysis: System-Level Biomimicry in Built-Environment Design.

Complex systems challenges like those facing 21st-century humanity, require system-level solutions that avoid siloed or unnecessarily narrow responses. System-level biomimicry aims to identify and adopt design approaches that have been developed and refined within ecosystems over 3.8 billion years of evolution. While not new, system-level biomimetic solutions have been less widely applied in urban design than the 'form' and 'process' level counterparts. This paper explores insights from a selection of system-level case studies in the built environment, using meta-analysis to investigate common challenges and priorities from these projects to support knowledge-sharing and continued development in the field. Using a grounded research approach, common themes are distilled, and findings presented regarding success and barriers to implementation and scaling. Considering the findings, and drawing on complex adaptive systems theory, the paper posits opportunities to facilitate broader implementation and mainstreaming of system-level biomimetic design approaches in the built environment.