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RNA G-quadruplexes (rG4) have recently emerged as major regulatory elements in both mRNA and non-coding RNA. In order to investigate the biological roles of rG4 structures, chemists have developed a variety of highly specific and potent ligands. All of these ligands bind to the rG4s by stacking on top of them. The binding specificity is demonstrated by comparison to other structures such as duplex or three-way junctions. It remains unclear whether rG4-ligands merely stabilize fully formed rG4 structures, or if they actively participate in the folding of the rG4 structure through their association with an unfolded RNA sequence. In order to elucidate the innate steps of ligand-rG4 associations and mechanisms robust in vitro techniques, including FRET, electrophoretic mobility shift assays and reverse transcriptase stalling assays, were used to examine the capacity of five well-known G4 ligands to induce rG4 structures derived from either long non-coding RNAs or from synthetic RNAs. It was found that both PhenDC3 and PDS induce rG4 formation in single RNA strands. This discovery has important implications for the interpretation of RNA-seq experiments. Overall, in vitro data that can assist biochemists in selecting the optimal G4-ligands for their RNA cellular experiments are presented, and the effects induced by these ligands on the rG4s are also considered., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Coronavirus disease 2019 (COVID-19) disproportionally affects pregnant women and their newborn; however, little is known about variables that modulate maternal-fetal immune response to infection., Methods: We prospectively studied socioeconomic, biologic, and clinical factors affecting humoral immunity in 87 unvaccinated pregnant women hospitalized in Buenos Aires for symptoms consistent with COVID-19., Results: The number of days between symptom onset and childbirth predicted maternal and newborn virus spike protein receptor binding domain (RBD)-specific immunoglobulin G (IgG). These findings suggest newborns may benefit less when mothers deliver soon after COVID-19 infection. Similarly, a longer time between symptom onset and birth predicted higher in utero transfer of maternal IgG and its concentration in cord blood. Older gestational age at birth was associated with lower maternal to cord blood IgG ratio. Of women with confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, 87% developed RBD-specific IgA responses in breast milk within 96 hours of childbirth. IgA was not significantly associated with time from infection but correlated with maternal serum IgG and placental transfer., Conclusions: These results demonstrate the combined role of biologic, clinical, and socioeconomic variables associated with maternal RBD-specific antibodies and supports early vaccination strategies for COVID-19 in socioeconomically vulnerable pregnant women., Clinical Trials Registration: NCT04362956., (© The Author(s) 2021. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Amoebic Gill Disease (AGD), caused by the protozoan extracellular parasite Paramoeba perurans (P. perurans) is a disease affecting Atlantic salmon (Salmo salar). This study investigated the gill transcriptomic profile of pre-clinical AGD using RNA-sequencing (RNA-seq) technology. RNA-seq libraries generated at 0, 4, 7, 14 and 16 days post infection (dpi) identified 19,251 differentially expressed genes (DEGs) of which 56.2% were up-regulated. DEGs mapped to 224 Gene Ontology (GO) terms including 140 biological processes (BP), 45 cellular components (CC), and 39 molecular functions (MF). A total of 27 reference pathways in the Kyoto Encyclopedia of Genes and Genomes (KEGG) and 15 Reactome gene sets were identified. The RNA-seq data was validated using real-time, quantitative PCR (qPCR). A host immune response though the activation of complement and the acute phase genes was evident at 7 dpi, with a concurrent immune suppression involving cytokine signalling, notably in interleukins, interferon regulatory factors and tumour necrosis factor-alpha (tnf-α) genes. Down-regulated gene expression with involvement in receptor signalling pathways (NOD-like, Toll-like and RIG-1) were also identified. The results of this study support the theory that P. perurans can evade immune surveillance during the initial stages of gill colonisation through interference of signal transduction pathways., (© 2021. The Author(s).)

Introduction: Neonatal autopsy is a valuable, critical diagnostic method to provide genetic counseling for future pregnancies., Population and Methods: Retrospective study including all neonatal autopsies performed on deceased neonates at Clínica y Maternidad Suizo Argentina between January 1998 and December 2006. The rate of autopsies was established; the diagnosis indicated in the medical record was compared to autopsy findings., Results: Out of 227 deceased infants, 135 autopsies were performed (rate: 59.5%). Concordance was complete in 25% of autopsies. New information was found in 26%, which had significant implications for genetic counseling., Conclusions: The rate of autopsies was 59.5%. Pathological and clinical correlation and unsuspected findings with implications for genetic counseling demonstrate the relevance of performing neonatal autopsies systematically.

Objective: To evaluate the effectiveness and safety of a T-piece resuscitator compared with a self-inflating bag for providing mask ventilation to newborns at birth., Study Design: Newborns at ≥26 weeks gestational age receiving positive-pressure ventilation at birth were included in this multicenter cluster-randomized 2-period crossover trial. Positive-pressure ventilation was provided with either a self-inflating bag (self-inflating bag group) with or without a positive end-expiratory pressure valve or a T-piece with a positive end-expiratory pressure valve (T-piece group). Delivery room management followed American Academy of Pediatrics and International Liaison Committee on Resuscitation guidelines. The primary outcome was the proportion of newborns with heart rate (HR)≥100 bpm at 2 minutes after birth., Results: A total of 1027 newborns were included. There was no statistically significant difference in the incidence of HR≥100 bpm at 2 minutes after birth between the T-piece and self-inflating bag groups: 94% (479 of 511) and 90% (466 of 516), respectively (OR, 0.65; 95% CI, 0.41-1.05; P=.08). A total of 86 newborns (17%) in the T-piece group and 134 newborns (26%) in the self-inflating bag group were intubated in the delivery room (OR, 0.58; 95% CI, 0.4-0.8; P=.002). The mean±SD maximum positive inspiratory pressure was 26±2 cm H2O in the T-piece group vs 28±5 cm H2O in the self-inflating bag group (P<.001). Air leaks, use of drugs/chest compressions, mortality, and days on mechanical ventilation did not differ significantly between groups., Conclusion: There was no difference between the T-piece resuscitator and a self-inflating bag in achieving an HR of ≥100 bpm at 2 minutes in newborns≥26 weeks gestational age resuscitated at birth. However, use of the T-piece decreased the intubation rate and the maximum pressures applied., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Background/purpose: Perinatal testicular torsion (PTT) is defined as testicular torsion occurring prenatally or within the first 30 days of life. The aim of this study was to evaluate the data obtained from patients with PTT and propose principles of management based on clinical, surgical, and histologic findings., Methods: A retrospective analysis of 27 boys seen between 1990 and 2005 with surgically documented PTT was conducted. Patients were divided into 2 groups: A, prenatal testicular torsion; B, postnatal testicular torsion. The presence of acute scrotal inflammatory signs defined the urgency to operate., Results: There were 4 clinical pictures in group A: A1, patients with a nubbin testis (n = 3); A2, patients with a small and hard testis (n = 12); A3, patients with a normal-sized and hard testis (n = 8); and A4, patients with an acute scrotum (n = 2). Group B (n = 2) presented no sign after birth and later developed an acute scrotum. Surgical exploration and histologic examination showed clear signs of a long-standing testicular torsion in groups A1, A2, and A3 or a recent-onset testicular torsion in groups A4 and B. Only one testis could be salvaged (group B)., Conclusions: Clinical signs correlated very well with surgical and histologic findings and can define the need and the urgency to operate. Although testicular salvage rate is very low, the affected side always should be explored to confirm the diagnosis and to fix or remove the affected testicle. The contralateral scrotum also should be explored because of the risk of asynchronous contralateral testicular torsion.

We report on a female newborn with holoprosencephaly, craniosynostosis, and multiple congenital anomalies including cloverleaf skull, Dandy-Walker malformation, bilateral microphthalmia, cleft soft palate, congenital scoliosis, hypoplastic nails and coarctation of aorta. Some of these features are consistent with the diagnosis of the Genoa syndrome, (MIM 601370) a rare autosomal recessive disorder recently described. The findings of other serious and previously undescribed malformations, however, raises the possibility of a newly recognized disorder., (Copyright 2001 Wiley-Liss, Inc.)

The administration of oxygen to infants via nasal cannulas is now a common practice in neonatal units although the inspired oxygen concentration reaching the patient's airway is unknown. We measured the hypopharyngeal oxygen concentration in 10 infants who were receiving oxygen via nasal cannulas and assessed the impact of changes in the flow rate and inspired oxygen concentration. Weaning these infants by reducing the flow rate, even if changes are slight, produces clinically important changes in the oxygen concentration reaching the airway. Such changes are poorly tolerated by infants with chronic lung disease. Changing the flow rate and inspired oxygen concentration, rather than the flow rate alone, provides greater precision and is likely to avoid excessive and abrupt changes in the oxygen concentration reaching the airway.