Benzo[a]pyrene impairs the migratory pattern of human gonadotropin-releasing-hormone-secreting neuroblasts

Benzo[a]pyrene (BaP) is a widespread pollutant that can act as an endocrine disrupting compound (EDC) and interferes with reproductive function. The central regulatory network of the reproductive system is mediated by gonadotropin-releasing hormone (GnRH) neurons, which originate in the olfactory placode and, during ontogenesis, migrate into the hypothalamus. Given the importance of the migratory process for GnRH neuron maturation, we investigated the effect of BaP (10 µM for 24 h) on GnRH neuroblasts isolated from the human fetal olfactory epithelium (FNCB4). BaP exposure significantly reduced the mRNA level of genes implicated in FNCB4 cell migration and affected their migratory ability. Our findings demonstrate that BaP may interfere with the central neuronal network controlling human reproduction affecting GnRH neuron maturation.

Migratory pattern of the coronavirus disease 2019 and high fatality rates among kidney transplant recipients: report from the Brazilian Multicenter Cohort Study

Introduction: The unprecedented coronavirus disease 2019 (COVID-19) pandemic has affected kidney transplant (KT) recipients, with worldwide fatality rates around 25%. Considering the well-known Brazilian socio-demographic disparities, this report describes for the first time the main outcomes of COVID-19 in KT recipients according to Brazilian geographic regions. Methods: This multicenter national retrospective analysis included data from KT recipients with confirmed COVID-19 between March and November 2020. Results: Thirty-five of the 81 centers (57% of KT activity in Brazil) reported 1,680 patients with COVID-19. The Northeast was the first to reach the peak in the number of infections. The Southeast, due to its population density, contributed with the largest number of patients. Patients had a median age of 52 years, 76% had hypertension and 34% diabetes, 75% were recipients of a deceased donor, and the time interval between diagnosis and transplantation was 5.9 years. In 53% of patients, immunosuppression was adjusted, and clinical support varied according to geographic region. Hospitalization was required for 65% of the patients, 35% of them needed intensive care, 25% mechanical ventilation, and 23% renal replacement therapy. The 90-day overall fatality was 21%, being 23% in the Southeast, 16% in the Northeast, and 19% in the Central-west and South regions. Conclusion: The migratory pattern of the pandemic among KT recipients followed that of the general population and the outcomes were influenced by regional features. COVID-19 in KT recipients was associated with high utilization of health-care resources and higher fatality rates than those reported in the general population.

Bistable Mathematical Model of Neutrophil Migratory Patterns After LPS-Induced Epigenetic Reprogramming

The highly controlled migration of neutrophils toward the site of an infection can be altered when they are trained with lipopolysaccharides (LPS), with high dose LPS enhancing neutrophil migratory pattern toward the bacterial derived source signal and super-low dose LPS inducing either migration toward an intermediary signal or dysregulation and oscillatory movement. Empirical studies that use microfluidic chemotaxis-chip devices with two opposing chemoattractants showed differential neutrophil migration after challenge with different LPS doses. The epigenetic alterations responsible for changes in neutrophil migratory behavior are unknown. We developed two mathematical models that evaluate the mechanistic interactions responsible for neutrophil migratory decision-making when exposed to competing chemoattractants and challenged with LPS. The first model, which considers the interactions between the receptor densities of two competing chemoattractants, their kinases, and LPS, displayed bistability between high and low ratios of primary to intermediary chemoattractant receptor densities. In particular, at equilibrium, we observe equal receptor densities for low LPS (< 15ng/mL); and dominance of receptors for the primary chemoattractant for high LPS (> 15ng/mL). The second model, which included additional interactions with an extracellular signal-regulated kinase in both phosphorylated and non-phosphorylated forms, has an additional dynamic outcome, oscillatory dynamics for both receptors, as seen in the data. In particular, it found equal receptor densities in the absence of oscillation for super-low and high LPS challenge (< 0.4 and 1.1 <LPS< 375 ng/mL); equal receptor densities with oscillatory receptor dynamics for super-low LPS (0.5 < LPS< 1.1ng/mL); and dominance of receptors for the primary chemoattractant for super-high LPS (>376 ng/mL). Predicting the mechanisms and the type of external LPS challenge responsible for neutrophils migration toward pro-inflammatory chemoattractants, migration toward pro-tolerant chemoattractants, or oscillatory movement is necessary knowledge in designing interventions against immune diseases, such as sepsis.

Narrow Rupture of the 2020 Mw 7.4 La Crucecita, Mexico, Earthquake

On 23 June 2020, a large (Mw 7.4) interplate thrust earthquake struck near the town of La Crucecita in the state of Oaxaca in southern Mexico, following a 55-yr interseismic period. A seismic source model is well constrained by teleseismic waveforms, static Global Positioning System offsets, and tsunami data, suggesting that the earthquake occurred on the slab interface at a dip of ∼23°, with a narrow elliptical asperity concentrating around a shallow depth of ∼20 km. The rupture propagates bilaterally from the hypocenter, and the down-dip rupture is restricted to ∼25 km by slow slip events (SSEs). The down-dip shear stress is released by SSEs during the interseismic period, limiting the earthquake magnitude and possibly resulting in the characteristic earthquake. The 2020 La Crucecita event, thus, is a good reminder to assess the seismic and tsunami potential in this region. The stress changes caused by the coseismic slip of the 2017 Mw 8.2 Chiapas earthquake are too small to trigger the 2020 La Crucecita earthquake. However, combined with the postseismic afterslip effects that play a leading role, it greatly promotes the eventual occurrence of the La Crucecita event. The results demonstrate the importance of considering postseismic afterslip, when evaluating seismic hazard and its migratory pattern.

Temples, Festivals, and Common Knowledge

This chapter explores the forms that Rome's festival and pilgrimage culture took as mirrored in the literary tradition. Religious festivals fabricated new molds for civic self-awareness and common knowledge that were then filled in by new arrivals to the mid-Republican city. By the late third century, Latins, Italians, and assorted non-Romans were making their way to Rome for ludi, in a migratory pattern that anticipated the post-Punic War influx of concern to Fannius. Social interaction at the games enhanced not only their knowledge of Roman institutions and their knowledge of one another but also their aggregative understanding of the extent to which others were becoming more knowledgeable about Roman institutions. This traffic in knowledge is part of Rome's mid-Republican state formation story.

Using temporally explicit habitat suitability models to infer the migratory pattern of a large mobile shark

Conservation and management measures for large mobile sharks are more effective when information on migratory patterns and environmental cues are known. In the absence of long-term monitoring data or tracking programs, available information is based on occasional catch or sighting records from a variety of sources, usually constrained in space and time. This study demonstrates the utility of developing temporally explicit habitat suitability (HS) models to infer the migratory pattern of large mobile sharks. Bimonthly presence-only HS models (MaxEnt algorithm) were developed for the broadnose sevengill shark (Notorynchus cepedianus) in the southwest Atlantic based on an exhaustive collection of data records and ecologically relevant predictors. The six final models showed good predictive power and were evaluated with independent data. A migratory pattern characterized by two main displacements was inferred from the models. We show that HS models can be applied as a no-cost, desk-based alternative to infer broadscale movements of large mobile sharks. This methodology is relevant as an important first step toward informing management plans in data-poor and financially limited regions or regions under urgent conservation need.