Changes in ADAR RNA editing patterns in CMV and ZIKV congenital infections.

BACKGROUND: RNA editing is a process that increases transcriptome diversity, often through Adenosine Deaminases Acting on RNA (ADARs) that catalyze the deamination of adenosine to inosine. ADAR editing plays an important role in regulating brain function and immune activation, and is dynamically regulated during brain development. Additionally, the ADAR1 p150 isoform is induced by interferons in viral infection and plays a role in antiviral immune response. However, the question of how virus-induced ADAR expression affects host transcriptome editing remains largely unanswered. This question is particularly relevant in the context of congenital infections, given the dynamic regulation of ADAR editing during brain development, the importance of this editing for brain function, and subsequent neurological symptoms of such infections, including microcephaly, sensory issues, and other neurodevelopmental abnormalities. Here, we begin to address this question, examining ADAR expression in publicly available datasets of congenital infections of human cytomegalovirus (HCMV) microarray expression data, as well as mouse cytomegalovirus (MCMV) and mouse/ human induced pluripotent neuroprogenitor stem cell (hiNPC) Zika virus (ZIKV) RNA-seq data. RESULTS: We found that in all three datasets, ADAR1 was overexpressed in infected samples compared to uninfected samples. In the RNA-seq datasets, editing rates were also analyzed. In all mouse infections cases, the number of editing sites was significantly increased in infected samples, albeit this was not the case for hiNPC ZIKV samples. Mouse ZIKV samples showed altered editing of well-established protein-recoding sites such as Gria3, Grik5, and Nova1, as well as editing sites that may impact miRNA binding. CONCLUSIONS: Our findings provide evidence for changes in ADAR expression and subsequent dysregulation of ADAR editing of host transcriptomes in congenital infections. These changes in editing patterns of key neural genes have potential significance in the development of neurological symptoms, thus contributing to neurodevelopmental abnormalities. Further experiments should be performed to explore the full range of editing changes that occur in different congenital infections, and to confirm the specific functional consequences of these editing changes.

Ensemble Sensing Using Single-Molecule DNA Copolymers.

While single-molecule sensing has offered ultimate mass sensitivity at the precision of individual molecules, it requires a longer time to detect analytes at lower concentrations when analyte binding to single-molecule probes becomes diffusion-limited. Here, we solved this accuracy problem in the concentration sensitivity determination by using single-molecule DNA homopolymers, in which up to 473 identical sensing elements (DNA hairpins) were introduced by rolling circle amplification. Surprisingly, the DNA homopolymers containing as few as 10 tandem hairpins displayed ensemble unfolding/refolding transitions, which were exploited to recognize microRNAs (miRNAs) that populated unfolded hairpins. Within 20 min, the femtomolar detection limit for miRNAs was observed, 6 orders of magnitude better than standalone hairpins. By incorporating different hairpin probes in an alternating DNA copolymer, multiplex recognition of different miRNAs was demonstrated. These DNA co-polymers represent new materials for innovative sensing strategies that combine the single-molecule precision with the accuracy of ensemble assays to determine concentration sensitivities.

ADAR Editing in Viruses: An Evolutionary Force to Reckon with.

Adenosine Deaminases that Act on RNA (ADARs) are RNA editing enzymes that play a dynamic and nuanced role in regulating transcriptome and proteome diversity. This editing can be highly selective, affecting a specific site within a transcript, or nonselective, resulting in hyperediting. ADAR editing is important for regulating neural functions and autoimmunity, and has a key role in the innate immune response to viral infections, where editing can have a range of pro- or antiviral effects and can contribute to viral evolution. Here we examine the role of ADAR editing across a broad range of viral groups. We propose that the effect of ADAR editing on viral replication, whether pro- or antiviral, is better viewed as an axis rather than a binary, and that the specific position of a given virus on this axis is highly dependent on virus- and host-specific factors, and can change over the course of infection. However, more research needs to be devoted to understanding these dynamic factors and how they affect virus-ADAR interactions and viral evolution. Another area that warrants significant attention is the effect of virus-ADAR interactions on host-ADAR interactions, particularly in light of the crucial role of ADAR in regulating neural functions. Answering these questions will be essential to developing our understanding of the relationship between ADAR editing and viral infection. In turn, this will further our understanding of the effects of viruses such as SARS-CoV-2, as well as many others, and thereby influence our approach to treating these deadly diseases.

Factors associated with pelvic fracture-related arterial bleeding during trauma resuscitation: a prospective clinical study.

OBJECTIVES: To determine predictors of pelvic fracture-related arterial bleeding (PFRAB) from the information available in the Emergency Department (ED). DESIGN: Prospective cohort study. SETTING: Single level-1 Trauma Center. PATIENTS: In a 3-year period ending in December 2008, consecutive high-energy pelvic fracture patients older than 18 years were included. Patients who arrived >4 hours after injury or dead on arrival were excluded. Patient management followed advanced trauma life support and institutional guidelines. Collected data included patient demographics, mechanism of injury, vital signs, acid-base status, fluid resuscitation, trauma scores, fracture patterns, procedures, and outcomes. Potential predictors were identified using standard statistical tests: Univariate analysis, Pearson correlation (r), receiver operator characteristic, and decision tree analysis. INTERVENTION: Observational study. OUTCOME MEASURES: PFRAB was determined based on angiography or computed tomography angiogram or laparotomy findings. RESULTS: Of the 143 study patients, 15 (10%) had PFRAB. They were significantly older, more severely injured, more hypotensive, more acidotic, more likely to require transfusions in the ED, and had higher mortality rate than non-PFRAB patients. No single variable proved to be a strong predictor but some had a significant correlation with PFRAB. Useful predictors identified were worst base deficit (BD), receiver operator characteristic (0.77, cutoff: 6 mmol/L, r = 0.37), difference between any 2 measures of BD within 4 hours (ΔBD) >2 mmol/L, transfusion in ED (yes/no), and worst systolic blood pressure <104 mm Hg. Demographics, injury mechanism, fracture pattern, temperature, and pH had poor predictive value. CONCLUSIONS: BD <6 mmol/L, ΔBD >2 mmol/L, systolic blood pressure <104 mm Hg, and the need for transfusion in ED are independent predictors of PFRAB in the ED. These predictors can be valuable to triage blunt trauma victims for pelvic hemorrhage control with angiography. LEVEL OF EVIDENCE: Prognostic Level I. See Instructions for Authors for a complete description of levels of evidence.

Efficacy and safety of emergency non-invasive pelvic ring stabilisation.

BACKGROUND: Urgent non-invasive pelvic ring stabilisation (pelvic binding, PB) in shocked patients is recommended by state and institutional guidelines regardless of the fracture pattern. The purpose of this study was to determine the adherence to the guidelines, efficacy of the technique and identification of potential adverse effects associated with PB. PATIENTS AND METHODS: A 41-month retrospective analysis of the prospective pelvic fracture database was undertaken at a level 1 trauma centre. High-energy pelvic fractures were included in the analysis with exclusion of the A type injuries (AO/OTA classification) and patients who were dead on arrival. Collected data included patient demographics, injury severity score, fracture classification, application and timing of PB, associated injuries, physiological parameters, resuscitation fluids and outcomes. Pre and post-PB radiographs were reviewed. The potential effects of the PB on soft tissue (femoral vessel, bladder and rectal injury) complications were assessed by independent experts. RESULTS: 115 patients with high-energy B and C type pelvic ring injuries were included. Thirty-six (31%) patients presented in haemorrhagic shock on arrival. A total of 43 pelvic bindings were performed, 18 of them on shocked patients. The adherence to the guidelines was 50% (18/36) overall. Analysing fracture types of shocked patients the adherence was: B1 80%, B2 20%, B3 20%, C1 66%, C2 86%, C3 33%. The alignment of the pelvis was improved or perfect on post-PB radiographs in 68% and had not changed in 21%. In some cases of B2 and B3 type injuries the PB increased the deformity after application (11%). There were 10 deaths (8.7%) in the study group, with 4 deaths attributed to acute pelvic bleeding. Two of these had PB applied and two were identified as potential for improvement. One femoral artery injury, four bladder injuries and three rectum injuries were identified in patients who had PB applied. Association between the PB and these injuries is unlikely. CONCLUSION: The adherence to the guidelines should be improved with further education and system development. The good effect of the technique was evident on radiographs. Although in some lateral compression fracture patterns the deformity increased, no hazards were associated with the use of PB.