Predominance of A2063G mutant strains in the Mycoplasma pneumoniae epidemic in children: A clinical and epidemiological study in 2023 in Wuhan, China.

OBJECTIVES: The prevalence of respiratory infectious diseases has changed in the post-COVID-19 epidemic era, and mycoplasma pneumoniae (MP) infection in children has attracted wide attention. METHODS: Children hospitalized for pneumonia in Wuhan, China, in 2023 were enrolled. Respiratory secretions were obtained for the targeted next-generation sequencing (tNGS) including mutation of MP. Pulmonary inflammation was divided into bronchopneumonia and pulmonary consolidation/atelectasis according to lung computed tomography imaging. RESULTS: Of the 667 pediatric pneumonia, 478 were MP positive (72%). The positive rate of MP detected by tNGS increased from April, and MP had become the primary pathogen of pneumonia in children in 2023. The 23S rRNA mutations were all A2063G, accounting for 85% of detected MP. The clinical symptoms of the mutant and wild-type strains were similar, with half of them experiencing atelectasis and lung consolidation. Early bronchoscopic lavage combined with azithromycin in pediatric pulmonary consolidation was an effective therapy strategy, which could be an alternative selection to MP pneumonia treatment. CONCLUSIONS: A2063G mutant strain MP was the primary pathogen of mycoplasma pneumoniae in children recently, which was often complicated by extra-pulmonary symptoms and complications.

Epigenetic programming mediates abnormal gut microbiota and disease susceptibility in offspring with prenatal dexamethasone exposure.

Prenatal dexamethasone exposure (PDE) can lead to increased susceptibility to various diseases in adult offspring, but its effect on gut microbiota composition and the relationship with disease susceptibility remains unclear. In this study, we find sex-differential changes in the gut microbiota of 6-month-old infants with prenatal dexamethasone therapy (PDT) that persisted in female infants up to 2.5 years of age with altered bile acid metabolism. PDE female offspring rats show abnormal colonization and composition of gut microbiota and increased susceptibility to cholestatic liver injury. The aberrant gut microbiota colonization in the PDE offspring can be attributed to the inhibited Muc2 expression caused by decreased CDX2 expression before and after birth. Integrating animal and cell experiments, we further confirm that dexamethasone could inhibit Muc2 expression by activating GR/HDAC11 signaling and regulating CDX2 epigenetic modification. This study interprets abnormal gut microbiota and disease susceptibility in PDT offspring from intrauterine intestinal dysplasia.

Chitinase 3-like 1 plays a pivotal role in airway response of RSV infection via regulating DC functional transition.

BACKGROUND: Dendritic cells (DCs) contribute to immune imbalance and airway hyperresponsiveness (AHR) induced by respiratory syncytial virus (RSV). The aim of present study was to explore the mechanism of RSV regulating naive T cell differentiation through DCs. METHODS: We generated a Lentivirus shRNA expression vector to knock down CHI3L1 in mouse lungs and bone marrow-derived dendritic cells (BMDCs). Then we investigated the effect of CHI3L1 knockdown on MAPK/ERK pathway, PI3K/AKT pathway, mature DCs represented by molecular markers, naive T cell differentiation and related cytokine expression in vitro and in vivo models of RSV. RESULTS: RSV elevated CHI3L1 expression in lung DCs and BMDCs. Knockdown of CHI3L1 impeded RSV-induced activation of MAPK/ERK and PI3K/AKT signaling pathways, attenuated CD86 and OX40L expression in mature DCs, reduced the proportion of Th2 and Th17 cells, and increased the proportion of Treg cells. In addition, by blocking CHI3L1, RSV-infected mice shown relief of airway resistance, the downregulation of Th2/Th17 like cytokines IL-4, IL-13 and IL-17 levels, and the upregulation of IL-10. CONCLUSION: Our data show that CHI3L1 promotes RSV induced immune imbalance and airway hyperresponsiveness by regulating the functional transformation of DCs.

Diagnosis, treatment, and prevention of monkeypox in children: an experts' consensus statement.

Monkeypox is a zoonotic disease. Since the first human monkeypox case was detected in 1970, it has been prevalent in some countries in central and western Africa. Since May 2022, monkeypox cases have been reported in more than 96 non-endemic countries and regions worldwide. As of September 14, 2022, there have been more than 58,200 human monkeypox cases, and there is community transmission. The cessation of smallpox vaccination in 1980, which had some cross-protection with monkeypox, resulted in a general lack of immunity to monkeypox, which caused global concern and vigilance. As of September 14, 2022, there are four monkeypox cases in China, including three in Taiwan province and one in Hong Kong city. Previous foreign studies have shown that children are vulnerable to monkeypox and are also at high risk for severe disease or complications. In order to improve pediatricians' understanding of monkeypox and achieve early detection, early diagnosis, early treatment,  and early disposal, we have organized national authoritative experts in pediatric infection, respiratory, dermatology, critical care medicine, infectious diseases, and public health and others to formulate this expert consensus, on the basis of the latest "Clinical management and infection prevention and control for monkeypox" released by The World Health Organization, the "guidelines for diagnosis and treatment of monkeypox (version 2022)" issued by National Health Commission of the People's Republic of China and other relevant documents. During the development of this consensus, multidisciplinary experts have repeatedly demonstrated the etiology, epidemiology, transmission, clinical manifestations, laboratory examinations, diagnosis, differential diagnosis, treatment, discharge criteria, prevention, disposal process, and key points of prevention and control of suspected and confirmed cases.

Alveolar macrophages and airway hyperresponsiveness associated with respiratory syncytial virus infection.

Respiratory syncytial virus (RSV) is a ubiquitous pathogen of viral bronchiolitis and pneumonia in children younger than 2 years of age, which is closely associated with recurrent wheezing and airway hyperresponsiveness (AHR). Alveolar macrophages (AMs) located on the surface of the alveoli cavity are the important innate immune barrier in the respiratory tract. AMs are recognized as recruited airspace macrophages (RecAMs) and resident airspace macrophages (RAMs) based on their origins and roaming traits. AMs are polarized in the case of RSV infection, forming two macrophage phenotypes termed as M1-like and M2-like macrophages. Both M1 macrophages and M2 macrophages are involved in the modulation of inflammatory responses, among which M1 macrophages are capable of pro-inflammatory responses and M2 macrophages are capable of anti-proinflammatory responses and repair damaged tissues in the acute and convalescent phases of RSV infection. Polarized AMs affect disease progression through the alteration of immune cell surface phenotypes as well as participate in the regulation of T lymphocyte differentiation and the type of inflammatory response, which are closely associated with long-term AHR. In recent years, some progress have been made in the regulatory mechanism of AM polarization caused by RSV infection, which participates in acute respiratory inflammatory response and mediating AHR in infants. Here we summarized the role of RSV-infection-mediated AM polarization associated with AHR in infants.

Human Parvovirus B19 Nonstructural Protein 1 Regulates GATA1 Expression via the Notch Signaling Pathway in K562 Cell Line.

BACKGROUND: Human parvovirus B19 (B19) infection can affect the hematopoietic arrest in fetus by hindering the differentiation and maturation of erythroid progenitor cells. B19 nonstructural protein 1 (NS1) has been shown to inhibit the differentiation of erythroid progenitor cells. The goal of this study is to explore the role of B19 NS1 in the regulation of GATA1 and Notch signaling pathway in hematopoietic cells. METHODS: The B19 NS1 expression plasmid was reconstituted, and the possibility of NS1 regulating GATA1 and GATA2 expression modulated by Notch-Hes pathway was tested by qRT-PCR and western blot. Immunofluorescence assays were conducted to visualize pNS1 in K562 cells. RESULTS: We demonstrate that B19 NS1 inhibited GATA1 and induced Hes1/Hes5, which is involved in the activation of Notch signaling pathway. Meanwhile, NS1 exhibited promoting effects on GATA2 expression. Activation of the Notch signaling pathway up-regulated its downstream transcriptional repressor family Hes, thereby inhibiting the expression of GATA gene in K562 cells. CONCLUSIONS: The results show that B19 NS1 protein negatively regulates GATA1 related nuclear transcription and may interfere with hematopoietic cell differentiation.

Inversion Effect of Hand Postures: Effect of Visual Experience Over Long and Short Term.

Some researchers argue that holistic processing is unique to face recognition supported by the face inversion effect. However, findings such as the body inversion effect challenge the face processing-specificity hypothesis, thus supporting the expertise hypothesis. Few studies have explored a possible hand inversion effect which could involve special processing similar to the face and body. We conducted four experiments to investigate the time course and flexibility of the hand posture inversion effect. We utilized a same/different discrimination task (Experiments 1 and 2), an identification task (Experiment 3), and a training paradigm involving the exposure of different hand orientations (Experiment 4). The results show the hand posture inversion effect (with fingers up as upright orientation) was not initially observed during the early phase of testing, but occurred in later phases. This suggests that both lifetime experience and recent exposure affect the hand posture inversion effect. We also found the hand posture inversion effect, once established, was stable across days and remained consistent across different tasks. In addition, the hand posture inversion effect for specific orientations could be obtained with short-term training of a given orientation, indicating the cognitive process is flexible.

Respiratory Syncytial Virus Nonstructural Protein 1 Promotes 5-Lipoxygenase via miR-19a-3p.

Background: Respiratory syncytial virus (RSV) infection can regulate the expression of a wide range of noncoding microRNAs (miRNAs), in which mir-19a-3p can participate in airway inflammatory response by regulating 5-lipoxygenase (5-LO) pathway. RSV nonstructural protein (NS) 1 is involved in the airway hyperresponsiveness during RSV infection. Methods: The expression levels of miR-19a-3p and inflammatory signaling-related indicators were detected using quantitative real-time PCR and western blot analyses on the A549 cells transfected with NS1 expression plasmids (pNS1). The 5-LO-mediated inflammatory signaling pathway was assessed when the miR-19a-3p or 5-LO was inhibited. Results: The immunofluorescence analysis showed that the plasmid-mediated NS1 protein was observed in both the cytoplasm and nucleus. The expression level of miR-19a-3p was significantly upregulated in the pNS1 or RSV-treated cells, which was reversed by the NS1 small interfering RNA. In addition, pNS1 also upregulated the expression of 5-LO, interleukin-5 (IL-5), and leukotriene B4 (LTB4), which was also significantly inhibited by the miR-19a-3p antagonists. The 5-LO inhibitor MK886 prevented the increase in the expression level of IL-5 induced by pNS1. Conclusions: These results suggested that the RSV NS1 might play an important role in the pathogenesis of RSV by activating the 5-LO and subsequent inflammatory cytokines through miR-19a-3p.

The Influence of Growth Mindset on the Mental Health and Life Events of College Students.

Growth mindset refers to our core belief that our talents can be developed through practice, which may influence our thoughts and behaviors. Growth mindset has been studied in a variety of fields, including education, sports, and management. However, few studies have explored whether differences in individuals' growth mindsets influence college students' self-reported mental health. Using the Growth Mindset Scale, Adolescent Self-rating Life Events Checklist, and SCL-90 Scale, data was collected from 2,505 freshmen in a University in China. Findings revealed that the students within the growth mindset group scored significantly lower on "mental health issues" and "stress due to life events" than the students in the fixed mindset group. Our findings suggest that individuals with a growth mindset are less prone to mental health problems than individuals with a fixed mindset.

Differential congenital cytomegalovirus infection in dichorionic diamniotic twins-A case report and literature review.

BACKGROUND: Cases of differential congenital cytomegalovirus (CMV) infection in twins are rarely reported. The chance of congenital infection and the clinical outcome of monochorionic diamniotic or dichorionic diamniotic twins are highly uncertain. CASES PRESENTATION: We reported a case of differential congenital CMV infection in dichorionic diamniotic twins. Despite being exposed to the same maternal environment and similar genetic background, twins reacted differently to maternal infection and presented with non-concordant infection status. The potential mechanism of discordant infection from aspects of type of chorion and placenta and immune status has been discussed through literature review. CONCLUSION: CMV infection can present as differential congenital infection in twin pregnancy, with various clinical symptoms. Fetal cellular immune function may be involved in the pathogenesis.

Respiratory syncytial virus nonstructural protein 1 breaks immune tolerance in mice by downregulating Tregs through TSLP-OX40/OX40L-mTOR axis.

Respiratory syncytial virus (RSV) infection in early life is associated strongly with the subsequent development and exacerbation of asthma, however, the mechanism is still ambiguous. In this study, we identified that RSV nonstructural protein (NS) 1 plays a critical role. Plasmid-mediated overexpression of NS1 induced significant airway hyperresponsiveness, eosinophilia, and mucus hyperproduction in mice. In the pNS1 group, there were markedly elevated proportions of Th2 and Th17 cells, while Th1 and Foxp3+ regulatory T cells (Tregs) significantly declined compared with the control group. Serum concentrations of interleukin (IL)-4, IL-5, IL-6, IL-17, transforming growth factor-beta, and tumor necrosis factor-alpha increased but levels of interferon-gamma and interleukin-10 declined in pNS1 group. Besides, NS1 caused a significant rise of serum thymic stromal lymphopoietin (TSLP) and OX40L levels, and a neutralizing mAb anti-OX40L was capable of promoting RSV clearance and attenuating the airway allergic inflammation caused by pNS1. Otherwise, OX40L-blocking counteracts the inhibitory effect of pNS1 on Tregs in the spleen. RSV NS1 caused elevated levels of phospho-AKT, phospho-mTOR, and phospho-S6K1, which were partially attenuated by anti-OX40L. Moreover, a specific inhibitor of mTORC1 significantly relieved the inhibition of Foxp3 expression and Tregs differentiation. Together, the data indicate that RSV NS1 protein breaks immune tolerance and induces airway inflammation and hyperresponsiveness in mice. In this process, NS1-stimulated TSLP and OX40L play a major role by inhibiting the induction of Tregs, which is at least partially mediated by modulating AKT-mTOR signaling pathways.

miRNAs and Leukotrienes in Respiratory Syncytial Virus Infection.

MicroRNAs (miRNAs) are small, non-coding RNAs that regulate posttranscription by binding to 3'-untranslated regions of target mRNAs. Recent functional studies have elucidated mechanisms that miRNAs regulate leukotriene synthesis by perturbing arachidonic acid metabolism. Both microarrays and high-throughput sequencing revealed distinct differential expression of miRNAs in children with respiratory syncytial virus (RSV) infection compared with healthy controls. Abnormal miRNA expression may contribute to higher leukotriene levels, which is associated with airway hyperreactivity. Targeting miRNAs may benefit to restore the homeostasis of inflammatory reaction and provide new strategies to alleviate airway hyperreactivity induced by RSV. In this article, we provide an overview of the current knowledge about miRNAs modulating leukotrienes through regulation of arachidonic acid metabolism with a special focus on miRNAs aberrantly expressed in children with RSV infection.

Dynamic changes of acquired maternal SARS-CoV-2 IgG in infants.

At present, there are still ambiguous reports about the perinatal infection of infants born to mothers infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The dynamic characteristics of infantile serum antibodies born to mother with SARS-CoV-2 has not been well described. In this study, we analyzed the seroconversion of 27 newborns born to 26 pregnant women infected with SARS-CoV-2. The SARS-CoV-2 IgG positive rate of parturient was 80.8%, and half of their infants obtained maternal IgG. IgG transfer rates were 18.8% and 81.8% in those infants whose mother infected less and more than 2 weeks before delivery. In the first two months of life, the IgG level of infants dropped sharply to one tenth of that at birth. These results suggest that maternal SARS-CoV-2 IgG provides limited protection for infants.

Antibiotic Use Among Hospitalized Children and Neonates in China: Results From Quarterly Point Prevalence Surveys in 2019.

Background: Antimicrobial resistance is a significant clinical problem in pediatric practice in China. Surveillance of antibiotic use is one of the cornerstones to assess the quality of antibiotic use and plan and assess the impact of antibiotic stewardship interventions. Methods: We carried out quarterly point prevalence surveys referring to WHO Methodology of Point Prevalence Survey in 16 Chinese general and children's hospitals in 2019 to assess antibiotic use in pediatric inpatients based on the WHO AWaRe metrics and to detect potential problem areas. Data were retrieved via the hospital information systems on the second Monday of March, June, September and December. Antibiotic prescribing patterns were analyzed across and within diagnostic conditions and ward types according to WHO AWaRe metrics and Anatomical Therapeutic Chemical (ATC) Classification. Results: A total of 22,327 hospitalized children were sampled, of which 14,757 (66.1%) were prescribed ≥1 antibiotic. Among the 3,936 sampled neonates (≤1 month), 59.2% (n = 2,331) were prescribed ≥1 antibiotic. A high percentage of combination antibiotic therapy was observed in PICUs (78.5%), pediatric medical wards (68.1%) and surgical wards (65.2%). For hospitalized children prescribed ≥1 antibiotic, the most common diagnosis on admission were lower respiratory tract infections (43.2%, n = 6,379). WHO Watch group antibiotics accounted for 70.4% of prescriptions (n = 12,915). The most prescribed antibiotic ATC classes were third-generation cephalosporins (41.9%, n = 7,679), followed by penicillins/ß-lactamase inhibitors (16.1%, n = 2,962), macrolides (12.1%, n = 2,214) and carbapenems (7.7%, n = 1,331). Conclusion: Based on these data, overuse of broad-spectrum Watch group antibiotics is common in Chinese pediatric inpatients. Specific interventions in the context of the national antimicrobial stewardship framework should aim to reduce the use of Watch antibiotics and routine surveillance of antibiotic use using WHO AWaRe metrics should be implemented.

Sepsis-induced acute lung injury in young rats is relieved by calycosin through inactivating the HMGB1/MyD88/NF-κB pathway and NLRP3 inflammasome.

PURPOSE: Sepsis is the primary cause for children's death worldwide. Calycosin (CAL) is an astragalus extract with anti-inflammatory, antioxidant and anti-tumor functions. This study aims to probe the role of CAL in alleviating sepsis-induced acute lung injury (ALI). PATIENTS AND METHODS: Cecal ligation and puncture (CLP) was carried out in young rats to induce sepsis model, which were then treated with CAL. The histopathological changes of the lung were observed, and the dry/wet (W/D) weight ratio of the lung was calculated to analyze pulmonary edema. Apoptosis was determined by the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) assay, and the contents of PaO2, PaCO2 and PaO2/FiO2 in the aortic blood of the rats were monitored by blood-gas analysis. In addition, lipopolysaccharide (LPS) was applied to treat Type II alveolar epithelial cells (AEC-II) to establish an in-vitro sepsis model. Cell viability was detected by the (4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and apoptosis was examined by flow cytometry. The expression of apoptosis-related proteins Bax, Bcl2 and Caspase3, as well as the HMGB1/MyD88/NF-κB axis and NLRP3 inflammasome were measured by Western Blot. The profiles of inflammatory factors (TNF-α, IL-1ß, and MCP-1) and oxidative stress markers (MDA, SOD, and CAT) in rat serum and AEC-II cells were also detected. RESULTS: CLP induced remarkable lung injury in the young rats. The administration of CAL significantly mitigated pathological injuries of rat lung, reduced lung edema and the apoptosis (labeled by TUNEL). In vitro, CAL treatment improved the damage of LPS-treated AEC-II cells. In addition, CAL dampened inflammation and oxidative stress both in vitro and in vivo, repressed the HMGB1/MyD88/NF-κB pathway and NLRP inflammasome activation induced by CLP or LPS. Interestingly, inhibiting HMGB1 (by ethyl pyruvate, EP) enhanced CAL-mediated protective effects against LPS in AEC-II cells. CONCLUSION: CAL alleviates sepsis-induced ALI in young rats by inhibiting the HMGB1/MyD88/NF-κB pathway and NLRP3 inflammasome activation.

Circular RNA circRNA_0000094 sponges microRNA-223-3p and up-regulate F-box and WD repeat domain containing 7 to restrain T cell acute lymphoblastic leukemia progression.

Circular RNAs (circRNAs) exert crucial regulatory effects in the pathogenesis of multiple tumors. This work aimed to probe into the role of circ_0000094 in T cell acute lymphoblastic leukemia (T-ALL). In this work, quantitative real-time polymerase chain reaction (qRT-PCR) was applied to quantify circ_0000094, miR-223-3p, and F-box and WD repeat domain containing 7 (FBW7) mRNA expressions in lymph node samples from T-ALL patients; Western blot was adopted to examine FBW7 protein expression in T-ALL cells; cell proliferation was detected by cell counting kit-8 (CCK-8) experiment; apoptosis was examined by flow cytometry; Transwell experiments were applied to assess T-ALL cell migration and invasion; the interactions among circ_0000094 and miR-223-3p, and miR-223-3p and FBW7 were validated by bioinformatics prediction, dual-luciferase reporter gene assay, and RNA immunoprecipitation experiment. We reported that, circ_0000094 expression was markedly reduced in T-ALL and circ_0000094 was predominantly located in the cytoplasm; gain-of-function and loss-of-function assays verified that circ_0000094 overexpression remarkably suppressed T-ALL cell proliferation, migration, and invasion, and enhanced apoptosis while knocking down circ_0000094 enhanced the malignant phenotypes of T-ALL cells; "rescue experiments" implied that miR-223-3p mimics partly reversed the inhibitory effects on the malignant phenotype of T-ALL cells due to the circ_0000094 up-regulation; circ_0000094 was proved to be a molecular sponge for miR-223-3p, and it could up-regulate the expression of FBW7 via repressing miR-223-3p expression. Taken together, it was concluded that circ_0000094 impedes T-ALL progression by modulating the miR-223-3p/FBW7 axis.

Transient Early Fine Motor Abnormalities in Infants Born to COVID-19 Mothers Are Associated With Placental Hypoxia and Ischemia.

Background: Long-term effects of Coronavirus Disease 2019 (COVID-19) on infants born to infected mothers are not clear. Fine motor skills are crucial for the development of infant emotional regulation, learning ability and social skills. Methods: Clinical information of 100 infants born to 98 mothers (COVID-19 n = 31, non-COVID-19 n = 67) were collected. Infants were follow-up up to 9 months post-partum. The placental tissues were examined for SARS-CoV-2 infection, pathological changes, cytokines, and mtDNA content. Results: Decreased placental oxygen and nutrient transport capacity were found in infected pregnant women. Increased IL-2, IL-6, TNF-α, and IFN-γ were detected in trophoblast cells and maternal blood of COVID-19 placentas. Elevated early fine motor abnormal-ities and increased serum TNI (troponin I) levels at delivery were observed in infants born to mothers with COVID-19. Increased abnormal mitochondria and elevated mtDNA content were found in the placentas from infected mothers. The placental mtDNA content of three infants with abnormal DDST were increased by 4, 7, and 10%, respectively, compared to the mean of the COVID-19 group. The Maternal Vascular Malperfusion (MVM), elevated cytokines and increased placental mtDNA content in mothers with COVID-19 might be associated with transient early fine motor abnormalities in infants. These abnormalities are only temporary, and they could be corrected by daily training. Conclusions: Babies born to COVID-19 mothers with mild symptoms appeared to have little or no excess long-term risks of abnormal physical and neurobehavioral development as compared with the infants delivered by non-COVID-19 mothers.

Recommendations for the Diagnosis, Prevention, and Control of Coronavirus Disease-19 in Children-The Chinese Perspectives.

Ever since SARS-CoV-2 began infecting people by the end of 2019, of whom some developed severe pneumonia (about 5%), which could be fatal (case fatality ~3.5%), the extent and speed of the COVID-19 outbreak has been phenomenal. Within 2.5 months (by March 18, 2020) over 191,127 COVID-19 patients have been identified in 161 countries. By then, over 700 pediatric patients were confirmed to have COVID-19 in China, with only about 58 diagnosed elsewhere. By now, there are thousands of children and adolescents infected. Chinese pediatricians would like to share their experience on how these patients were managed in China and the key recommendations that had guided them in meeting the evolving challenges. A group of experts were summoned by the Chinese Pediatric Society and Editorial Board of Chinese Journal of Pediatrics to extract informative data from a survey on confirmed COVID-19 pediatric patients in China. Consensus on diagnosis, management, and prevention of pediatric COVID-19 were drawn up based on the analysis of such data plus insights gained from the past SARS and MERS coronavirus outbreaks. Relevant cumulating experiences from physicians managing adult patients, expedited reports on clinical and scientific COVID-19 and SARS-CoV-2 data, and the National Health Committee guidelines on COVID-19 management were integrated into this proposal.