Discrimination and Aggregative Patterns among and between populations of Entamoeba spp.

Kin recognition facilitates the evolution of cooperation in animals, but its relevance in microorganisms and their behavior toward relatives remains unclear. The Entamoeba lineage constitutes an ideal model to determine the behavioral and signaling cues needed for aggregative preference. Chemical cues have been reported for E. histolytica but not E. dispar, suggesting cell-communication between con-specifics and behavioral differences with relevance for disease. Entamoeba varieties have been reported as ‘morphologically undistinguishable’. Two strains of E. invadens have been isolated from different hosts (VK-1: NS - Varanus komodoensis and IP1- serpentes) but were classified within the same ‘species’. Trophozoites of each strain aggregate only with members of their own variety, suggesting they are able to associate based on behavioral and chemical communication. Adaptations to different environments and horizontal gene exchange could have influenced diversification of each lineage. Measurable aggregation and behavioral cues in fluorescence micrographs of Entamoeba varieties suggest that these characteristics should be included in phylogenetic studies

Perspective From a Youth Environmental Activist: Why Adults Will Listen to Youth in Politics

This perspective article is divided between the account of an emerging youth political activist, Katelyn Higgins, and the subsequent collaborative research project she coordinated. After 10 years of experience in youth political action, Higgins worked with co-authors to develop a qualitative study to explore the processes underlying youth influence over local environmental policymaking. We present findings from that study to supplement her perspective. The study supported fourth and fifth grade teachers by offering a marine debris curriculum which encouraged students to share their knowledge with local community members through environmental activism events. At the first event, students aged 8–10 presented at a town hall meeting; we interviewed 16 adults in attendance. The second “event” was a series of video PSAs (Public Service Announcements) in which students from across the state of North Carolina, United States, explained the harms of marine debris. Those PSAs were emailed to local officials; we conducted follow-up interviews with two officials. Four themes emerged to characterize how adults responded to youth environmental activism: young people were inspiring; adults want to support young people; and adults view young people as able to provide leadership for local action and challenge the establishment. Youth leaders and those looking to support them should be encouraged by these results, as they suggest adults, including local public officials, consider youth voices valuable and uniquely situated to foster productive political processes for addressing marine debris. Future research should continue to explore the degree to which positive feelings expressed by adults translate to action

Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570