and Zemanate participated in creation of the study concept and data interpretation and were involved in data acquisition and drafting and editing the manuscript; and all authors had final approval of the manuscript, approved the final manuscript as submitted, and agree to be accountable for all aspects of the work.

BackgroundThe COVID-19 pandemic reached the Southern Hemisphere in the autumn of 2020, thus coinciding with its expected annual viral respiratory season. The potential impact of national strategies aimed at mitigating COVID-19 during the pandemic on the incidence of other critical viral lower respiratory tract infections (LRTIs) in children is unknown.MethodsWe analysed admission data for LRTIs from 22 paediatric intensive care units (PICUs) in four countries, part of a large international Latin American registry of children with acute respiratory failure (Red Colaborativa Pediátrica de Latinoamérica [LARed Network]).ResultsBetween January and August, there were 83% fewer PICU admissions for LRTIs in 2020 compared to the 2018/2019 average over the same period. Similar decreases were noted for PICU admissions due to respiratory syncytial virus and influenza (92% and 78%, respectively).ConclusionWe observed a striking reduction in PICU admissions due to viral LRTIs over winter, during the COVID-19 pandemic in South America.

IMPORTANCE Concussion is the most common form of traumatic brain injury (TBI). While most patients fully recover within 1 week of injury, a subset of patients might be at a higher risk of suicide. OBJECTIVE To assess the risk of suicide after concussion. DATA SOURCES We performed a systematic search of Medline (PubMed), Embase, PsycINFO, and Published International Literature on Traumatic Stress (PILOTS) from 1963 to May 1, 2017. We also searched Google Scholar and conference proceedings and contacted experts in the field to seek additional studies. STUDY SELECTION Studies that quantified the risk of suicide, suicide attempt, or suicidal ideation after a concussion and/or mild TBI were included. Studies that included children and adults, including military and nonmilitary personnel, were included. Two authors independently reviewed all titles and abstracts to determine study eligibility. DATA EXTRACTION AND SYNTHESIS Study characteristics were extracted independently by 2 trained investigators. Study quality was assessed using the Newcastle-Ottawa Scale. Study data were pooled using random-effects meta-analysis. MAIN OUTCOMES AND MEASURES The primary exposure was concussion and/or mild TBI, and the primary outcome was suicide. Secondary outcomes were suicide attempt and suicidal ideation. RESULTS Data were extracted from 10 cohort studies (n = 713 706 individuals diagnosed and 6 236 010 individuals not diagnosed with concussion and/or mild TBI), 5 cross-sectional studies (n = 4420 individuals diagnosed and 11 275 individuals not diagnosed with concussion and/or mild TBI), and 2 case-control studies (n = 446 individuals diagnosed and 8267 individuals not diagnosed with concussion and/or mild TBI). Experiencing concussion and/or mild TBI was associated with a 2-fold higher risk of suicide (relative risk, 2.03 [95% CI, 1.47-2.80]; I 2 = 96%; P < .001). In 2 studies that provided estimates with a median follow-up of approximately 4 years, 1664 of 333 118 individuals (0.50%) and 750 of 126 114 individuals (0.59%) diagnosed with concussion and/or mild TBI died by suicide. Concussion was also associated with a higher risk of suicide attempt and suicide ideation. The heightened risk of suicide outcomes after concussion was evident in studies with and without military personnel. CONCLUSIONS AND RELEVANCE Experiencing concussion and/or mild TBI was associated with a higher risk of suicide. Future studies are needed to identify and develop strategies to decrease this risk.

Recent evidence demonstrates the importance of microRNAs (miRNAs) in several human diseases, including solid and hematological malignancies, diabetes and diseases of the nervous system. However, little is known about the role that miRNAs play in the development and pathogenesis of lung diseases. Murine models of disease suggest that the loss of specific miRNAs is vital to lung development and modulation of the immune system that consequently results in the development of uncontrolled inflammation in the lung. Other studies have found that bacterial challenges also upregulate the expression of specific miRNAs. In this article, we will focus on miRNA involvement in lung development and the possibility that dysregulation and/or reactivation of miRNAs may contribute to lung disease. We will also review the role of miRNAs in the pathogenesis of specific diseases, such as lung cancer, sepsis and smoking-related lung disease.

Extracellular vesicles (EVs) are mRNA‐containing cell fragments shed into circulation during pathophysiological events. DNA methyltransferases (DNMT1, DNMT3A, and DNMT3B) regulate gene expression by modifying DNA methylation and altering transcription. Sepsis is a systemic insult resulting in vascular dysfunction, which can lead to shock and death. We analysed plasma from ICU patients for circulating EV numbers, defined as particles isolated from 1 mL plasma at 21,000xg, and DNMTs mRNA content as prognostic markers of septic shock. Compared to plasma from critically ill patients with or without sepsis, plasma from septic shock patients contained more EVs per mL, expressed as total DNMTs mRNAs over 5 days, and more individual DNMT mRNAs at each day. A comparison of EV‐DNMT1 (maintenance methylation) with EV‐DNMT3A+DNMT3B (de novo methylation) expression correlated highly with severity, and EVs from septic shock patients carried more total DNMT mRNAs and more DNMT3A+DNMT3B mRNAs than control or sepsis EVs. Total plasma EVs also correlated with sepsis severity. EV‐DNMT mRNAs load, when coupled with total plasma EV number, may be a novel method to diagnose septic shock upon ICU admittance and offer opportunities to more precisely intervene with standard therapy or other targeted interventions to regulate EV release and/or specific DNMT activity.