The COVID-19 infection in children and its association with the immune system, prenatal stress, and neurological complications

Advanced nanomedicines and immunotherapeutics to treat respiratory diseases especially COVID-19 induced thrombosis

Immunotherapy and associated immune regulation strategies gained huge attraction in order to be utilized for treatment and prevention of respiratory diseases. Engineering specifically nanomedicines can be used to regulate host immunity in lungs in the case of respiratory diseases including coronavirus disease 2019 (COVID-19) infection. COVID-19 causes pulmonary embolisms, thus new therapeutic options are required to target thrombosis, as conventional treatment options are either not effective due to the complexity of the immune-thrombosis pathophysiology. In this review, we discuss regulation of immune response in respiratory diseases especially COVID-19. We further discuss thrombosis and provide an overview of some antithrombotic nanoparticles, which can be used to develop nanomedicine against thrombo-inflammation induced by COVID-19 and other respiratory infectious diseases. We also elaborate the importance of immunomodulatory nanomedicines that can block pro-inflammatory signalling pathways, and thus can be recommended to treat respiratory infectious diseases.

Age-related transcript changes in type I interferon signaling in children and adolescents with long COVID

SARS-CoV-2 typically causes mild symptoms in children, but evidence suggests that persistent immunopathological changes may lead to long COVID (LC). To explore the interplay between LC and innate immunity, we assessed the type I interferon (IFN-I) response in children and adolescents with LC symptoms (LC; n = 28). This was compared with age-matched SARS-CoV-2 recovered participants without LC symptoms (MC; n = 28) and healthy controls (HC; n = 18). We measured the mRNA expression of IFN-I (IFN-α/β/ε/ω), IFN-I receptor (IFNAR1/2), and ISGs (ISG15, ISG56, MxA, IFI27, BST2, LY6E, OAS1, OAS2, OAS3, and MDA5) in PBMCs collected 3-6 months after COVID-19. LC adolescents (12-17 years) had higher transcript levels of IFN-β, IFN-ε, and IFN-ω than HC, whereas LC children (6-11 years) had lower levels than HC. In adolescents, increased levels of IFN-α, IFN-β, and IFN-ω mRNAs were found in the LC group compared with MC, while lower levels were observed in LC children than MC. Adolescents with neurological symptoms had higher IFN-α/β mRNA levels than MC. LC and MC participants showed decreased expression of ISGs and IFNAR1, but increased expression of IFNAR2, than HC. Our results show age-related changes in the expression of transcripts involved in the IFN-I signaling pathway in children and adolescents with LC.

Mesenchymal stem cell-derived extracellular vesicles for human diseases

Stem cell therapy is a novel approach for treating various severe and intractable diseases, including autoimmune disorders, organ transplants, tumors, and neurodegenerative diseases. Nevertheless, the extensive utilization of stem cells is constrained by potential tumorigenicity, challenges in precise differentiation, rejection concerns, and ethical considerations. Extracellular vesicles possess the ability to carry diverse bioactive factors from stem cells and deliver them to specific target cells or tissues. Moreover, they offer the advantage of low immunogenicity. Consequently, they have the potential to facilitate the therapeutic potential of stem cells, mitigating the risks associated with direct stem cell application. Therefore, the use of stem cell extracellular vesicles in clinical diseases has received increasing attention. This review summarizes advances in the use of extracellular vesicles from mesenchymal stem cells (MSC). MSC extracellular vesicles are used in the treatment of inflammatory diseases such as rheumatoid arthritis, liver injury, COVID-19, and allergies; in the repair of tissue damage in heart disease, kidney injury, and osteoarthritic diseases; as a carrier in the treatment of tumors; and as a regenerative agent in neurodegenerative disorders such as Alzheimer's and Parkinson's.

Management of neonates with maternal prenatal coronavirus infection and influencing factors

The coronavirus disease 2019 (COVID-19) in pregnancy causes adverse outcomes for both the mother and the fetus. Neonates are at risk of vertical transmission and in-utero infection. Additionally, intensive care unit (ICU) admission and impairment in the organ systems of the mother are associated with neonatal outcomes, including impaired intrauterine growth, prematurity, and neonatal ICU admission. The management of neonates born from infected mothers has changed over the progress of the pandemic. At the beginning of the pandemic, cesarean section, immediate separation of mother-infant dyads, isolation of neonates, and avoiding of skin-to-skin contact, breast milk, and breastfeeding were the main practices to reduce vertical and horizontal transmission risk in the era of insufficient knowledge. The effects of antenatal steroids and delayed cord clamping on COVID-19 were also not known. As the pandemic progressed, data showed that prenatal, delivery room, and postnatal care of neonates can be performed as pre-pandemic practices. Variants and vaccines that affect clinical course and outcomes have emerged during the pandemic. The severity of the disease and the timing of infection in pregnancy also influence maternal and neonatal outcomes. The knowledge and lessons from COVID-19 will be helpful for the next pandemic if it happens. IMPACT: Prenatal infection with COVID-19 is associated with adverse maternal and neonatal outcomes. Our review includes the management of neonates with prenatal COVID-19 infection exposure, maternal-fetal, delivery room, and postnatal care of neonates, clinical features, treatment of neonates, and influencing factors such as variants, vaccination, severity of maternal disease, and timing of infection during pregnancy. There is a growing body of data and evidence about the COVID-19 pandemic. The knowledge and lessons from the pandemic will be helpful for the next pandemic if it happens.

Neonatal outcomes of maternal prenatal coronavirus infection

The coronavirus disease 2019 (COVID-19) pandemic has led to significant changes in life and healthcare all over the world. Pregnant women and their newborns require extra attention due to the increased risk of adverse outcomes. Adverse pregnancy outcomes include intensive care unit (ICU) admission, pulmonary, cardiac, and renal impairment leading to mortality. Immaturity and variations of the neonatal immune system may be advantageous in responding to the virus. Neonates are at risk of vertical transmission and in-utero infection. Impaired intrauterine growth, prematurity, vertical transmission, and neonatal ICU admission are the most concerning issues. Data on maternal and neonatal outcomes should be interpreted cautiously due to study designs, patient characteristics, clinical variables, the effects of variants, and vaccination beyond the pandemic. Cesarean section, immediate separation of mother-infant dyads, isolation of neonates, and avoidance of breast milk were performed to reduce transmission risk at the beginning of the pandemic in the era of insufficient knowledge. Vertical transmission was found to be low with favorable short-term outcomes. Serious fetal and neonatal outcomes are not expected, according to growing evidence. Long-term effects may be associated with fetal programming. Knowledge and lessons from COVID-19 will be helpful for the next pandemic if it occurs. IMPACT: Prenatal infection with SARS-CoV-2 is associated with adverse maternal and neonatal outcomes. Our review includes the effects of COVID-19 on the fetus and neonates, transmission routes, placental effects, fetal and neonatal outcomes, and long-term effects on neonates. There is a growing body of data and evidence about the COVID-19 pandemic. Knowledge and lessons from the pandemic will be helpful for the next pandemic if it happens.

CHANGES IN SUBSET COMPOSITION AND PHAGOCYTIC ACTIVITY OF MONOCYTES IN CHILDREN WITH INFECTIOUS MONONUCLEOSIS UNDER EXPOSURE TO GM-CSF IN VITRO

The aim of the study was to investigate the features of changes in the subset composition of monocytes and their phagocytic activity in children with infectious mononucleosis (IM) under the influence of granulocyte-macrophage colony-stimulating factor (GM-CSF) in vitro. We examined 84 children aged 3 to 11 years with Epstein-Barr virus (EBV) infection. EBV infection was diagnosed on the basis of clinical signs of IM, a positive test for EBV DNA in blood lymphocytes and results of ELISA tests (EBV-VCAIgM (+), EBV-EA-DIgG (+)). The control group consisted of 40 practically healthy children of the same age range. Monocytes were obtained by the standard method of adhesion to plastic from mononuclear cells isolated from heparinized venous blood by density gradient centrifugation. The isolated monocytes were divided into two samples: control (without GM-CSF) and experimental (50 ng of GM-CSF per 1 ml of cell suspension). The subset composition and phagocytic activity of monocytes in both samples were determined by flow cytometry after incubation for 1 hour at 37C in a CO2-incubator. It was found that in children against the background of the development of IM, the subpopulation composition of monocytes in the blood changes and their phagocytic activity is impaired. It was found that the subset composition and phagocytic activity of the blood monocytes changed in children against the background of the development of IM. Changes in the subset composition of monocytes against the background of acute IM did not depend on the age group of children (3-6 and 7-11 years) and were characterized by an increase in the number of pro-inflammatory (intermediate) monocytes and a decrease in the content of anti-inflammatory (non-classical) monocytes. Features of violation of the phagocytic activity of the monocytes in children with IM depended on age. The phagocytic activity of all three subsets of the monocytes was reduced in children with IM 3-6 years old while children with IM 7-11 years old had reduced phagocytic activity only of intermediate and non-classical monocytes. The effect of GM-CSF in vitro on monocytes in patients with IM, regardless of the age of children, led to a significant increase in the level of anti-inflammatory monocytes while the phagocytic activity of cells changed less. An increase in the phagocytic number for classical monocytes after incubation with GM-CSF in vitro was noted in children with IM at the age of 3-6 years while the phagocytic index of this fraction of monocytes remained unchanged. The level of the phagocytic index increased only in classical monocytes of children with IM aged 7-11 years. The presented results determine the scientific and clinical value of studying the mechanisms of the effect of GM-CSF on cells of the immune system and prove that this cytokine can be used in a new immunotherapeutic strategy for the treatment of IM.

Neurological Involvement in Children with COVID-19 and MIS-C: A Retrospective Study Conducted for More than Two Years in a Pediatric Hospital

This study aimed to evaluate the type and severity of neurological involvement in children with SARS-CoV-2 infection or multisystem inflammatory syndrome in children (MIS-C) and compare these findings between the two groups. Children hospitalized with the diagnosis of COVID-19 or MIS-C at Meyer Children's Hospital between February 2020 and June 2022 were retrospectively studied. One hundred twenty-two patients were enrolled, 95 in the COVID-19 group and 27 in the MIS-C group. In the COVID-19 group, impairment of consciousness was found in 67.4% of patients, headache in 18.9% and about 16.8% of patients experienced seizures. In this group, three patients were diagnosed with arterial ischemic stroke and one patient was diagnosed with Guillain-Barré syndrome (GBS). In the MIS-C group, about 70% of patients experienced consciousness impairment, about 20% behavioral changes, and another 20% mood deflection. Neurological symptoms and signs were highly heterogeneous and could be differentiated in COVID-19 and MIS-C. Consciousness impairment remained the most frequent manifestation in both groups, potentially underlying an encephalopathy. We also highlight the importance of considering psychiatric symptoms in children with COVID-19 and/or MIS-C. Most neurological manifestations were mild in our series; however, severe complications such as ischemic stroke and GBS are worthy of note.

A systematic review of current status and challenges of vaccinating children against SARS-CoV-2

The coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has inflicted immense damage to countries, economies and societies worldwide. Authorized COVID-19 vaccines based on different platforms have been widely inoculated in adults, showing up to 100% immunogenicity with significant efficacy in preventing SARS-CoV-2 infections and the occurrence of severe COVID-19. It has also greatly slowed the evolution of SARS-CoV-2 variants, as shown in clinical trials and real-world evidence. However, the total dosage of COVID-19 vaccines for children is much smaller than that for adults due to limitations from parental concern of vaccine safety, presenting a potential obstacle in ending the COVID-19 pandemic. SARS-CoV-2 not only increases the risk of severe multisystem inflammatory syndrome (MIS-C) in children, but also negatively affects children's psychology and academics, indirectly hindering the maintenance and progress of normal social order. Therefore, this article examines the clinical manifestations of children infected with SARS-CoV-2, the status of vaccination against COVID-19 in children, vaccination-related adverse events, and the unique immune mechanisms of children. In particular, the necessity and challenges of vaccinating children against SARS-CoV-2 were highlighted from the perspectives of society and family. In summary, parental hesitancy is unnecessary as adverse events after COVID-19 vaccination have been proven to be infrequent, comprise of mild symptoms, and have a good prognosis.

An Explainable Machine Learning Pipeline for Stroke Prediction on Imbalanced Data

Stroke is an acute neurological dysfunction attributed to a focal injury of the central nervous system due to reduced blood flow to the brain. Nowadays, stroke is a global threat associated with premature death and huge economic consequences. Hence, there is an urgency to model the effect of several risk factors on stroke occurrence, and artificial intelligence (AI) seems to be the appropriate tool. In the present study, we aimed to (i) develop reliable machine learning (ML) prediction models for stroke disease; (ii) cope with a typical severe class imbalance problem, which is posed due to the stroke patients' class being significantly smaller than the healthy class; and (iii) interpret the model output for understanding the decision-making mechanism. The effectiveness of the proposed ML approach was investigated in a comparative analysis with six well-known classifiers with respect to metrics that are related to both generalization capability and prediction accuracy. The best overall false-negative rate was achieved by the Multi-Layer Perceptron (MLP) classifier (18.60%). Shapley Additive Explanations (SHAP) were employed to investigate the impact of the risk factors on the prediction output. The proposed AI method could lead to the creation of advanced and effective risk stratification strategies for each stroke patient, which would allow for timely diagnosis and the right treatments.

RETRACTED: The pathogenicity of COVID-19 and the role of pentraxin-3: An updated review study

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/policies/article-withdrawal). This article has been retracted at the request of the Editor-in-Chief. In investigating concerns regarding the contributions of the authors to this article, the editors reached out to the authors for an explanation. In addition to the concerns regarding the contribution of each author, the editors discovered suspicious changes in authorship between the original submission and the revised version of this paper. The names of the authors Ameer A Alameri and Zanko Hassan Jawhar were added to the revised version of the article without explanation and without the exceptional approval by the handling Editor, which is contrary to the journal policy on changes to authorship. The authors were unable to provide a reasonable explanation for either of the issues raised. The editor therefore feels that the findings of the manuscript cannot be relied upon and that the article needs to be retracted.

Spotlight on therapeutic efficiency of mesenchymal stem cells in viral infections with a focus on COVID-19

The SARS-COV-2 virus has infected the world at a very high rate by causing COVID-19 disease. Nearly 507 million individuals have been infected with this virus, with approximately 1.2% of these patients being dead, indicating that this virus has been out of control in many countries. While researchers are investigating how to develop efficient drugs and vaccines versus the COVID-19 pandemic, new superseded treatments have the potential to reduce mortality. The recent application of mesenchymal stem cells (MSCs) in a subgroup of COVID-19 patients with acute respiratory distress has created potential benefits as supportive therapy for this viral contagion in patients with acute conditions and aged patients with severe pneumonia. Consequently, within this overview, we discuss the role and therapeutic potential of MSCs and the challenges ahead in using them to treat viral infections, with highlighting on COVID-19 infection.

Hematologic manifestations of coronavirus disease 2019 in children: Case-series report and a review

On 11 March 2020, coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus (SARS-CoV-2) was declared as a pandemic by the World Health Organization (WHO). As the COVID-19 pandemic has ravaged worldwide, children have not been unaffected. Information gleaned from adult experience with the disease has aided in disease detection and treatment strategies in children. Numerous cases have been described in adult literature about hematologic manifestations of COVID-19. This case series aims to report several hematologic presentations in patients with COVID-19 and multisystem inflammatory syndrome in children (MIS-C, an immune-mediated reaction leading to severe COVID-19 illness) with and without a primary hematologic disorder.