Synthetic eco-evolutionary dynamics in simple molecular environment.

The understanding of eco-evolutionary dynamics, and in particular the mechanism of coexistence of species, is still fragmentary and in need of test bench model systems. To this aim we developed a variant of SELEX in vitro selection to study the evolution of a population of ∼1015 single-strand DNA oligonucleotide 'individuals'. We begin with a seed of random sequences which we select via affinity capture from ∼1012 DNA oligomers of fixed sequence ('resources') over which they compete. At each cycle ('generation'), the ecosystem is replenished via PCR amplification of survivors. Massive parallel sequencing indicates that across generations the variety of sequences ('species') drastically decreases, while some of them become populous and dominate the ecosystem. The simplicity of our approach, in which survival is granted by hybridization, enables a quantitative investigation of fitness through a statistical analysis of binding energies. We find that the strength of individual resource binding dominates the selection in the first generations, while inter- and intra-individual interactions become important in later stages, in parallel with the emergence of prototypical forms of mutualism and parasitism.

Serum antibody fingerprinting of SARS-CoV-2 variants in infected and vaccinated subjects by label-free microarray biosensor.

Both viral infection and vaccination affect the antibody repertoire of a person. Here, we demonstrate that the analysis of serum antibodies generates information not only on the virus type that caused the infection but also on the specific virus variant. We developed a rapid multiplex assay providing a fingerprint of serum antibodies against five different SARS-CoV-2 variants based on a microarray of virus antigens immobilized on the surface of a label-free reflectometric biosensor. We analyzed serum from the plasma of convalescent subjects and vaccinated volunteers and extracted individual antibody profiles of both total immunoglobulin Ig and IgA fractions. We found that Ig level profiles were strongly correlated with the specific variant of infection or vaccination and that vaccinated subjects displayed a larger quantity of total Ig and a lower fraction of IgA relative to the population of convalescent unvaccinated subjects.

Clinical course and peculiarities of Parechovirus and Enterovirus central nervous system infections in newborns: a single-center experience.

Parechovirus (HpEV) and Enterovirus (EV) infections in children mostly have a mild course but are particularly fearsome in newborns in whom they may cause aseptic meningitis, encephalitis, and myocarditis. Our study aimed to describe the clinical presentations and peculiarities of CNS infection by HpEV and EV in neonates. This is a single-center retrospective study at Istituto Gaslini, Genoa, Italy. Infants aged ≤ 30 days with a CSF RTq-PCR positive for EV or HpEV from January 1, 2022, to December 1, 2023, were enrolled. Each patient's record included demographic data, blood and CSF tests, brain MRI, therapies, length of stay, ICU admission, complications, and mortality. The two groups were compared to identify any differences and similarities. Twenty-five patients (15 EV and 10 HpEV) with a median age of 15 days were included. EV patients had a more frequent history of prematurity/neonatal respiratory distress syndrome (p = 0.021), more respiratory symptoms on admission (p = 0.012), and higher C-reactive protein (CRP) levels (p = 0.027), whereas ferritin values were significantly increased in HpEV patients (p = 0.001). Eight patients had a pathological brain MRI, equally distributed between the two groups. Three EV patients developed myocarditis and one HpEV necrotizing enterocolitis with HLH-like. No deaths occurred.  Conclusion: EV and HpEV CNS infections are not easily distinguishable by clinical features. In both cases, brain MRI abnormalities are not uncommon, and a severe course of the disease is possible. Hyper-ferritinemia may represent an additional diagnostic clue for HpEV infection, and its monitoring is recommended to intercept HLH early and initiate immunomodulatory treatment. Larger studies are needed to confirm our findings. What is Known: • Parechovirus and Enteroviruses are the most common viral pathogens responsible for sepsis and meningoencephalitis in neonates and young infants. • The clinical course and distinguishing features of Parechovirus and Enterovirus central nervous system infections are not well described. What is New: • Severe disease course, brain MRI abnormalities, and complications are not uncommon in newborns with Parechovirus and Enteroviruses central nervous system infections. • Hyper-ferritinemia may represent an additional diagnostic clue for Parechovirus infection and its monitoring is recommended.

Clinical Course, Laboratory Findings, and Prognosis of SARS-CoV-2 Infection in Infants up to 90 Days of Age: A Single-Center Experience and a Proposal for a Management Pathway.

AIM: To provide a comprehensive description of the clinical features, biochemical characteristics, and outcomes of infants up to 90 days old with COVID-19. Moreover, to assess the severity of the disease and propose an effective management pathway. METHODS: Retrospective single-center study spanning three years. Patient data includes age, sex, symptoms, comorbidities, blood and urine test results, cultures, admission, length of stay, therapies, intensive care unit admission, and mortality. RESULTS: A total of 274 patients were enrolled in the study, comprising 55% males. Among them, 60 patients (22%) were under the age of 29 days, while 214 (78%) fell within the 29 to 90 days age range. The overall incidence of SARS-CoV-2 infections was 0.28 per 10,000 Pediatric Emergency Department admissions. Blood inflammatory markers showed no significant abnormalities, and there were no recorded instances of positive blood cultures. Less than 1% of infants showed urinary tract infections with positive urine cultures, and 1.5% of patients had a concurrent RSV infection. Hospitalization rates were 83% for neonates and 67% for infants, with a median length of stay (LOS) of 48 h for both age groups. None of the patients required admission to the Pediatric or Neonatal Intensive Care Unit, and only one required High Flow Nasal Cannula (HFNC). No secondary serious bacterial infections were observed, and all hospitalized patients were discharged without short-term sequelae. No deaths were reported. DISCUSSION AND CONCLUSIONS: Infants with COVID-19 generally exhibit milder or asymptomatic forms of the disease, making home management a viable option in most cases. Blood tests, indicative of a mild inflammatory response, are recommended primarily for children showing symptoms of illness. Hospitalization precautions for infants without apparent illness or comorbidities are deemed unnecessary. Given the evolving nature of experiences with COVID-19 in infants, maintaining a high level of clinical suspicion remains imperative.

The usefulness of point-of-care ultrasound in dehydrated patients in a pediatric emergency department.

BACKGROUNDS: Dehydration is among the most common causes of Pediatric Emergency Department admission; however, no clinical signs, symptoms, or biomarkers have demonstrated sufficient sensitivity, specificity, or reliability to predict dehydration. METHODS: We conducted a prospective, monocentric, observational study at Giannina Gaslini Hospital, a tertiary care pediatric hospital. Our study aimed to compare inferior vena cava ultrasound measurement with volume depletion biomarkers to understand if point-of-care ultrasound could help grade, evaluate, and better manage dehydration in children presenting to the pediatric emergency department. We enrolled patients under the age of 14 who required blood tests in the suspect of dehydration; for each patient, we collected values of venous pH, natremia, bicarbonatemia, uric acid, chloremia, and blood urea nitrogen. For each patient, we performed two ultrasound scans to calculate the Inferior Vena Cava/Aorta area ratio and to assess the IVC collapsibility index; moreover, we described the presence of the "kiss sign" (100% IVC walls collapsing during the inspiratory phase). RESULTS: Patients with the "kiss sign" (25/65 patients, 38.5% of the total) showed worse blood tests, in particular, uric acid levels (p = 0.0003), bicarbonatemia (p = 0.001) and natriemia (p = 0.0003). Moreover, patients with the "kiss sign" showed a high frequency of ≥ 2 pathological blood tests (p = 0.0002). We found no statistical significant difference when comparing the IVC/Ao ratio and IVC-CI with the considered blood tests. CONCLUSIONS: The "kiss sign" seems to be related to worse hydration state, whereas IVC/Ao and IVC-CI are not. In an emergency setting, where physicians must take diagnostic-therapeutic decisions quickly, the presence of the "kiss sign" in patients suspected to be dehydrated can be a helpful tool in their management.

Fetal Myocarditis Associated With Maternal SARS-CoV-2 Infection.

We report the first case of significant fetal myocardial involvement associated with maternal SARS-CoV-2 infection, in which restoration of cardiac function at birth was noted. The demonstration of previous infection was supported by the quantification of humoral response in child and mother, in particular the presence of anti-N antibodies and through the detection of specific antibodies against the BA.4/5 variant.

Epidemiological and clinical evolution of multisystem inflammatory syndrome in children throughout the SARS-CoV-2 pandemic in a tertiary Italian children's hospital.

Multisystem inflammatory syndrome in children (MIS-C) is a potentially life-threatening disease temporally linked to SARS-CoV-2 whose incidence and clinical presentation may have been altered by the different SARS-CoV-2 variants and by vaccination. METHODS: We retrospectively collected the data of all MIS-C cases admitted to the Gaslini Children's Hospital, the hub for SARS-CoV-2 related diseases in Liguria region, Italy, from 01 October 2020, to 30 November 2022, evaluating the ratio between MIS-C cases and (1) COVID-19 paediatric cases in our region, (2) emergency department admissions and (3) emergency department febrile patients. We also compared MIS-C incidence in pre- post-vaccination periods. RESULTS: We observed a significant global decline in the incidence of MIS-Cover the four variant periods and after the starting of vaccination whereas clinical features, therapeutic management and severity did not significantly vary. CONCLUSIONS: In our setting, we demonstrated a significant decrease of MIS-C incidence according to the predominant variant and including not vaccinated children. Regardless of variant type, the patients showed similar phenotypes and severity throughout the pandemic. SARS-CoV-2 variants as well as immune protection after previous infections and/or vaccination may have interacted by playing different roles and reducing the incidence of MIS-C.

Difficult Intravascular Access in Pediatric Emergency Department: The Ultrasound-Assisted Strategy (DIAPEDUS Study).

Vein line positioning represents one of the first diagnostic and therapeutic steps in Pediatric Emergency Department (PED); however, the outcome of this maneuver is frequently not as expected, especially for difficult-to-access (DIVA) patients. The standard technique (visual-palpatory) has a low success rate; hence ultrasound (US) assistance has been suggested for DIVA patients, although controversial results have been obtained. Our study compared the success rate of an intravascular (IV) access procedure at the first attempt, with and without ultrasound assistance, in pediatric DIVA patients. Secondary objectives were the global success rate, the mean procedural time, the IV device's life span, and the complications rate. We conducted an observational, prospective, monocentric, no-profit cohort study enrolling 110 patients presenting to our ED, aged 0-21 years. All the patients were considered difficult-to-access patients according to the DIVA score (≥4) or history of previous difficult intravascular access. They were randomized into two homogeneous groups: 50 patients with the standard and 60 with the US-assisted technique. We obtained a significantly higher success rate at first attempt with the US-guided technique (90% vs 18%, p ≤ .00001). Moreover, the overall success rate was higher in the US group (95% vs 46%, p < .00001). The mean procedural time resulted significantly less in the US group (2.7 ± 2.2 min vs 10 ± 6.4 min, p < .0001), as well as the overall number of attempts to obtain a stable IV line (1.09 ± 0.34 attempts vs 2.38 ± 1.09 attempts, p < .0001). We experienced some post-procedural complications without differences in the two groups, although none were severe. Our study showed that bedside ultrasound assisting implantation of peripheral venous access in pediatric DIVA patients improves first-time success rate, overall success rate, procedural time, and patient comfort, reducing the number of attempts to obtain a stable IV line.

Ten new paediatric emergency medicine commandments.

AIM: We suggest the top ten tips that any clinician working in a pediatric emergency department should always keep in mind. METHODS: A literature review was conducted using, as a starting point, the previously published Ten Commandments for Emergency Medicine, Pediatric Emergency Medicine, and Perinatal Medicine. RESULTS AND CONCLUSION: A standard curriculum for pediatric emergency physicians is lacking. These ten commandments should be considered as advice for physicians who practice this profession every day and not as unbreakable rules established from above.

Individual, environmental and demographic factors may play a role in the prognosis of fatal and non-fatal paediatric drowning.

AIM: Drowning is a leading cause of unintentional death. Ongoing efforts are dedicated to preventing these tragic incidents. Our aim was to evaluate whether demographic, environmental and epidemiological characteristics of drowned children influence their prognosis. METHODS: Single-centre retrospective study spanning 12 years. Each patient's record included: age, sex, place of residence, presence of siblings, season of incident, location of event, associated trauma, loss of consciousness, need for cardiopulmonary resuscitation, intubation, admission to intensive care unit, length of stay and mortality. RESULTS: We enrolled 60 patients, with a mean age of 5.9 ± 3.4 years; 63.5% were male. Children who did not reside near the sea were significantly older than those who did (p = 0.01) and faced a higher risk of experiencing sea-related drowning (p = 0.05). No patients died. Loss of consciousness and need for cardiopulmonary resuscitation were recorded in 30 and 19 patients respectively. Seven patients sustained trauma. Only one patient requiring intubation. Pool-related drowning were associated with a higher incidence of needing cardiopulmonary resuscitation (p = 0.02). The need for cardiopulmonary resuscitation (p = 0.05) and the occurrence of trauma (p = 0.02) were identified as risk factors for a longer hospitalisation. CONCLUSION: Prevention and early initiation of cardiopulmonary resuscitation are essential for achieving a favourable prognosis. Identifying demographic and environmental risk factors may help identify other effective preventive measures.

Digital Detection of Single Virus Particles by Multi-Spot, Label-Free Imaging Biosensor on Anti-Reflective Glass.

Rapid detection of whole virus particles in biological or environmental samples represents an unmet need for the containment of infectious diseases. Here, an optical device enabling the enumeration of single virion particles binding on antibody or aptamers immobilized on a surface with anti-reflective coating is described. In this regime, nanoparticles adhering to the sensor surface provide localized contributions to the reflected field that become detectable because of their mixing with the interfering waves in the reflection direction. Thus, these settings are exploited to realize a scan-free, label-free, micro-array-type digital assay on a disposable cartridge, in which the virion counting takes place in wide field-of-view imaging. With this approach we could quantify, by enumeration, different variants of SARS-CoV-2 virions interacting with antibodies and aptamers immobilized on different spots. For all tested variants, the aptamers showed larger affinity but lower specificity relative to the antibodies. It is found that the combination of different probes on the same surface enables increasing specificity of detection and dynamic range.

Walking Ferroelectric Liquid Droplets with Light.

The motion of ferroelectric liquid sessile droplets deposited on a ferroelectric lithium niobate substrate can be controlled by a light beam of moderate intensity irradiating the substrate at a distance of several droplet diameters from the droplet itself. The ferroelectric liquid is a nematic liquid crystal, in which almost complete polar ordering of the molecular dipoles generates an internal macroscopic polarization locally collinear to the mean molecular long axis. Upon entering the ferroelectric phase, droplets are either attracted toward the center of the beam or repelled, depending on the side of the lithium niobate exposed to light irradiation. Moreover, moving the beam results in walking the ferroelectric droplet over long distances on the substrate. This behavior is understood as due to the coupling between the polarization of the ferroelectric droplet and the polarization photoinduced in the irradiated region of the lithium niobate substrate. Indeed, the effect is not observed in the conventional nematic phase, suggesting the crucial role of the ferroelectric liquid crystal polarization.

Supratentorial Demyelinating Lesions Following Severe Acute Respiratory Syndrome Coronavirus-2 Infection: A Pediatric Case Report.

INTRODUCTION: Most coronavirus disease 2019 (COVID-19) pediatric patients are asymptomatic; however, several neurological manifestations associated with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection have been reported. Demyelinating events such as acute disseminated encephalomyelitis have been recently included among potential complications of COVID-19. CASE REPORT: We describe the case of a 12-year-old boy who developed central nervous system demyelinating lesions following SARS-CoV-2 infection. Two months prior he had been diagnosed with panuveitis but was otherwise healthy. Three weeks after testing positive for SARS-CoV-2, he started to complain of right temporal headache associated with right orbital pain without vision impairment. Brain magnetic resonance imaging showed large leukodystrophy-like demyelinating lesions. Standard electroencephalogram revealed a slow activity on the right hemisphere. His clinical and electroencephalographic course was favorable, with a good response to corticosteroid therapy and infusions of intravenous immunoglobulins. Delayed but complete resolution of brain lesions was noted on imaging. CONCLUSION: Our case contributes to broaden the knowledge regarding the spectrum of possible complications of SARS-CoV-2 infection. The relative lack of clinical manifestations in our patient can be seen as a warning not to underestimate even mild neurological symptoms correlated with COVID-19.

A liquid crystal world for the origins of life.

Nucleic acids (NAs) in modern biology accomplish a variety of tasks, and the emergence of primitive nucleic acids is broadly recognized as a crucial step for the emergence of life. While modern NAs have been optimized by evolution to accomplish various biological functions, such as catalysis or transmission of genetic information, primitive NAs could have emerged and been selected based on more rudimental chemical-physical properties, such as their propensity to self-assemble into supramolecular structures. One such supramolecular structure available to primitive NAs are liquid crystal (LC) phases, which are the outcome of the collective behavior of short DNA or RNA oligomers or monomers that self-assemble into linear aggregates by combinations of pairing and stacking. Formation of NA LCs could have provided many essential advantages for a primitive evolving system, including the selection of potential genetic polymers based on structure, protection by compartmentalization, elongation, and recombination by enhanced abiotic ligation. Here, we review recent studies on NA LC assembly, structure, and functions with potential prebiotic relevance. Finally, we discuss environmental or geological conditions on early Earth that could have promoted (or inhibited) primitive NA LC formation and highlight future investigation axes essential to further understanding of how LCs could have contributed to the emergence of life.