Improving the efficiency and biosafety of respiratory syncytial virus identification using a nucleic acid extraction-free reagent.

Respiratory syncytial virus (RSV) is the most important virus that causes lower respiratory tract disease in children; efficient viral identification is an important component of disease prevention and treatment. Here, we developed and evaluated a ready-to-use (RTU) nucleic acid extraction-free direct reagent for identification of RSV (RTU-Direct test) in clinical samples. The limit of detection (LOD) of the RSV RTU-Direct test was consistent with the LOD of the standard test using extracted nucleic acids. The virus inactivation ability of RTU-Direct reagent was confirmed by viral infectivity assays involving RTU-Direct-treated samples containing RSV and human coronavirus OC43. RSV RNA stability was significantly better in RTU-Direct reagent than in conventional virus transport medium (VTM) at room temperature and 4°C (p < 0.05). The clinical performance of the RTU-Direct test was evaluated using 155 respiratory specimens from patients with suspected RSV infection. Positive agreement between the RTU-Direct test and the VTM standard test was 100% (42/42); negative agreement was 99.1% (112/113), and the kappa statistic was 0.968 (p < 0.001). The distributions of Ct values did not significantly differ between the RTU-Direct test and the standard test (p > 0.05). Overall, the RTU-Direct reagent can improve the efficiency and biosafety of RSV detection, while reducing the cost of detection.

Seroprevalence of neutralizing antibodies against the respiratory syncytial virus in healthy adults in Guangzhou, southern China.

Respiratory syncytial virus (RSV) is the major cause of pneumonia and bronchiolitis in infants and young children and mediates substantial morbidity and mortality in the elderly and immunocompromised globally. The development of a safe and effective RSV vaccine and an optimized neutralizing antibody (NAb) with strong virus-neutralizing activity is appealing. To gain some detailed knowledge of the humoral immune response to RSV subgroup A (RSV-A) and RSV-B, we investigated the seroprevalence of pre-existing NAbs by using the microneutralization assay in healthy adult from Guangzhou, southern China. We found that the overall seropositive rate was 84.86% for anti-RSV NAbs. Furthermore, the seropositive rates were 68.47% and 73.61% for anti-RSV-A NAbs and anti-RSV-B NAbs, respectively. In addition, although the seropositive rates and NAb levels were not associated with the blood type, type AB individuals displayed higher seropositive rates for anti-RSV-A NAbs with high titer (≥ 288) and anti-RSV-B NAbs, especially those with moderate titer (≥ 72 to < 288). The seropositive rates and titers were comparable between anti-RSV-A NAbs and anti-RSV-B NAbs in the AB blood type group. Interestingly, only when the NAb titer of the serum to RSV-A was not less than 288, was it not less than 18 to RSV-B, and vice versa. These results would be helpful for a better understanding of the human serum NAb responses to RSV-A and RSV-B.

[Value of anti-neutrophil cytoplasmic antibody in assessing the severity of bronchiolitis obliterans in children].

OBJECTIVE: To study the value of anti-neutrophil cytoplasmic antibody (ANCA) in assessing the severity of bronchiolitis obliterans (BO) in children. METHODS: A prospective analysis was performed on 59 children who were diagnosed with BO from June 2009 to October 2014. ELISA was used to measure the concentrations of myeloperoxidase (MPO)-ANCA and proteinase 3 (PR3)-ANCA in serum. According to the results of ELISA, the children were divided into three groups: double-negative ANCA (n=22), single-positive ANCA (n=17), and double-positive ANCA (n=20). The three groups were compared in terms of the scores of BO risk factors, clinical symptoms, chest high-resolution computed tomography (HRCT), and lung pathology on admission, as well as the changes in the expression level of ANCA and the scores of clinical symptoms and chest HRCT over time. RESULTS: Compared with the double-negative ANCA group, the double-positive ANCA group had a significantly higher score of BO risk factors (P<0.05), and the single-positive ANCA group and the double-positive ANCA group had significantly higher scores of clinical symptoms, chest HRCT, and lung pathology (P<0.05). The children were followed up for 6 months after discharge, and there were significant reductions in MPO-ANCA and PR3-ANCA titers from admission and discharge to the end of follow-up (P<0.05), as well as a significant reduction in the score of clinical symptoms from admission to the end of follow-up (P<0.05), while there was no significant change in the score of chest HRCT from admission to the end of follow-up (P>0.05). The single-positive ANCA and double-positive ANCA groups still had a significantly higher score of clinical symptoms than the double-negative ANCA group (P<0.05). CONCLUSIONS: The expression level of ANCA is correlated with the severity of BO in children and thus has certain clinical significance in disease evaluation.

Paramyxoviruses respiratory syncytial virus, parainfluenza virus, and human metapneumovirus infection in pediatric hospitalized patients and climate correlation in a subtropical region of southern China: a 7-year survey.

To investigate the features of paramyxovirus respiratory syncytial virus (RSV), parainfluenza virus (PIV), and human metapneumovirus (HMPV) infection and determine the effect of meteorological conditions in Guangzhou, a subtropical region of southern China. We collected 11,398 respiratory samples from hospitalized pediatric patients with acute respiratory illness between July 2009 and June 2016 in Guangzhou. The samples were tested simultaneously for 18 respiratory pathogens using real-time PCR. Local meteorological data were also collected for correlation analysis. Of 11,398 patients tested, 5606 (49.2%) patients tested positive for one or more pathogens; RSV, PIV, and HMPV were the first, sixth, and ninth most frequently detected pathogens, in 1690 (14.8%), 502 (4.4%), and 321 (2.8%) patients, respectively. A total 17.9% (4605/5606) of patients with positive results had coinfection with other pathogens. Significant differences were found in the prevalence of RSV, PIV, and HMPV among all age groups (p < 0.001). RSV and HMPV had similar seasonal patterns, with two prevalence peaks every year. PIV appeared alternatively with RSV and HMPV. Multiple linear regression models were established for RSV, PIV, and HMPV prevalence and meteorological factors (p < 0.05). RSV and PIV incidence was negatively correlated with monthly mean relative humidity; RSV and HMPV incidence was negatively correlated with sunshine duration; PIV incidence was positively correlated with mean temperature. We described the features of paramyxovirus infection in a subtropical region of China and highlighted the correlation with meteorological factors. These findings will assist public health authorities and clinicians in improving strategies for controlling paramyxovirus infection.

Epidemiology and clinical characteristics of human coronaviruses OC43, 229E, NL63, and HKU1: a study of hospitalized children with acute respiratory tract infection in Guangzhou, China.

Human coronaviruses (HCoV) OC43, 229E, NL63, and HKU1 are common respiratory viruses which cause various respiratory diseases, including pneumonia. There is a paucity of evidence on the epidemiology and clinical manifestations of these four HCoV strains worldwide. We collected 11,399 throat swabs from hospitalized children with acute respiratory tract infection from July 2009 to June 2016 in Guangzhou, China. These were tested for four strains of HCoV infection using real-time polymerase chain reaction (PCR). HCoV-positive patients were then tested for 11 other respiratory pathogens. 4.3% (489/11399) of patients were positive for HCoV, of which 3.0% were positive for OC43 (346/11399), 0.6% for 229E (65/11399), 0.5% for NL63 (60/11399), and 0.3% for HKU1 (38/11399). Patients aged 7-12 months had the highest prevalence of HCoV and OC43 when compared with other age groups (p < 0.001). The peak seasons of infection varied depending on the HCoV strain. Patients infected with a single strain of HCoV infection were less likely to present fever (≥ 38 °C) (p = 0.014) and more likely to present pulmonary rales (p = 0.043) than those co-infected with more than one HCoV strain or other respiratory pathogens. There were also significant differences in the prevalence of certain symptoms, including coughing (p = 0.032), pneumonia (p = 0.026), and abnormal pulmonary rales (p = 0.002) according to the strain of HCoV detected. This retrospective study of the prevalence of four HCoV strains and clinical signs among a large population of pediatric patients in a subtropical region of China provides further insight into the epidemiology and clinical features of HCoV.

Epidemiology of HBoV1 infection and relationship with meteorological conditions in hospitalized pediatric patients with acute respiratory illness: a 7-year study in a subtropical region.

BACKGROUND: Human bocavirus 1 (HBoV1) is an important cause of acute respiratory illness (ARI), yet the epidemiology and effect of meteorological conditions on infection is not fully understood. To investigate the distribution of HBoV1 and determine the effect of meteorological conditions, hospitalized pediatric patients were studied in a subtropical region of China. METHODS: Samples from 11,399 hospitalized pediatric patients (≤14 years old), with ARI were tested for HBoV1 and other common respiratory pathogens using real-time PCR, between July 2009 and June 2016. In addition, local meteorological data were collected. RESULTS: Of the 11,399 patients tested, 5606 (49.2%) were positive for at least one respiratory pathogen. Two hundred forty-eight of 11,399 (2.2%) were positive for HBoV1 infection. Co-infection was common in HBoV1-positive patients (45.2%, 112/248). A significant difference in the prevalence of HBoV1 was found in patients in different age groups (p < 0.001), and the peak prevalence was found in patients aged 7-12 months (4.7%, 56/1203). Two HBoV1 prevalence peaks were found in summer (between June and September) and winter (between November and December). The prevalence of HBoV1 was significantly positively correlated with mean temperature and negatively correlated with mean relative humidity, and the mean temperature in the preceding month had better explanatory power than the current monthly temperature. CONCLUSIONS: This study provides a better understanding of the characteristics of HBoV1 infection in children in subtropical regions. Data from this study provide useful information for the future control and prevention of HBoV1 infections.

[Association of ORMDL3 single nucleotide polymorphisms with lysophosphatidylcholine and apolipoprotein B levels in children with asthma].

OBJECTIVE: To study the association of ORMDL3 single nucleotide polymorphisms (SNP) with lysophosphatidylcholine (LysoPC) and apolipoprotein B (apoB) levels. METHODS: A total of 300 children diagnosed with bronchial asthma between January 2010 and December 2012 were selected for the asthma group, and 298 children diagnosed with upper respiratory tract infection in the same period were selected for the control group. Serum LysoPC and apoB levels were measured using enzyme-linked immunosorbent assay. Genotype analysis was performed using the TaqMan probe. RESULTS: LysoPC and apoB levels were significantly higher in the asthma group than in the control group (P<0.01). Among children with various genotypes of ORMDL3 gene at locus rs12603332, the asthma group had significantly higher LysoPC and apoB levels than the control group (P<0.01). Among the children with asthma, those with CC genotype had significantly higher LysoPC and apoB levels than those with CT and TT genotypes (P<0.01). CONCLUSIONS: LysoPC and apoB may intervene in the pathological process of asthma. Pro-inflammatory gene ORMDL3 SNP rs12603332 may be associated with high LysoPC and apoB levels, which leads to the occurrence of childhood asthma.

Plastic Bronchitis in Children: A Review of 55 Cases over a 10-Year Period.

Objective: To summarize the clinical characteristics and treatment experiences of patients with plastic bronchitis (PB). Methods: All patients who were diagnosed with PB by bronchoscopic removal of tree-like casts at a single institution from January 2012 to May 2022 were retrospectively reviewed. Demographic and clinical data were retrieved from electronic patient records. Results: A total of 55 patients, with a median age of 5.3 years, were eligible for the study. Nineteen cases had underlying diseases, among which asthma was the most common. The median course of the disease before admission was 11 days. Clinical symptoms were characterized by cough and fever, while moist rales (78.2%) and dyspnea (61.8%) were the most common signs. The most common laboratory finding was elevated C-reactive protein (58.2%). Patchy opacity was the most frequent radiographic finding (81.2%), followed by consolidation (60.0%) and pleural effusion (43.6%). Respiratory pathogens were detected in 41 cases, and M. pneumoniae was the most common one (41.8%), followed by adenovirus (20.0%) and influenza B virus (10.9%). The casts were removed by alveolar lavage, combined with ambroxol immersion (63.6%) and forceps (30.9%). Patients received an average of 2.3 bronchoscopies, and the median time for the first procedure was 3 days after admission. Antibiotics were given to all patients, methylprednisolone to 33 (60.0%), and gamma globulin to 25 (45.5%). A total of 53 cases were improved with an overall mortality rate of 3.6%. Conclusions: PB in children is characterized by airway obstruction, mostly caused by respiratory infections, and timely removal of the cast by bronchoscopy is the most effective treatment.

A novel variant in a Chinese boy with lysinuric protein intolerance: A case report and literature review.

We report a case of a 4-year-old boy with lysinuric protein intolerance in China. The patient presented with interstitial lung disease with obvious clubbing of the fingers and toes. During the course of diagnosis and treatment, we found he was averse to a high-protein diet, intolerant to activity, and had a history of diarrhea and fractures. Physical examination revealed hepatosplenomegaly and clubbing of the fingers and toes. Next-generation sequencing revealed compound heterozygous mutations (c.1387delG, c.958T > C) in SLC7A7, which was confirmed as a disease-causing gene for lysinuric protein intolerance. After a literature review, we found that c.958T > C had not been previously reported, and summarized the clinical and genetic characteristics of patients from different continents. His symptoms improved significantly after 3 months of being on a low-protein diet, supplementation with lysine, citrulline, carnitine, and trace elements, and oral corticosteroid treatment for 2 months. The patient is still under follow-up.

An injectable and photocurable methacrylate-silk fibroin/nano-hydroxyapatite hydrogel for bone regeneration through osteoimmunomodulation.

Tissue engineering has emerged as a promising approach for addressing bone defects. Most of the traditional 3D printing materials predominantly relying on polymers and ceramics. Although these materials exhibit superior osteogenic effects, their gradual degradation poses a limitation. Digital light processing (DLP) 3D bioprinting that uses natural biomaterials as bioinks has become one of the promising strategies for bone regeneration. In this study, we introduce a hydrogel biomaterial derived from silk fibroin (SF). Notably, we present the novel integration of nano-hydroxyapatite (nHA) into the hydrogel, forming a composite hydrogel that rapidly cross-links upon initiation. Moreover, we demonstrate the loading of nHA through non-covalent bonds in SilMA. In vitro experiments reveal that composite hydrogel scaffolds with 10 % nHA exhibit enhanced osteogenic effects. Transcriptomic analysis indicates that the composite hydrogel promotes bone regeneration by inducing M2 macrophage polarization. Furthermore, rat femoral defect experiments validate the efficacy of SilMA/nHA10 in bone regeneration. This study synthesis of a simple and effective composite hydrogel bioink for bone regeneration, presenting a novel strategy for the future implementation of digital 3D printing technology in bone tissue engineering.

FUNDC1-induced mitophagy protects spinal cord neurons against ischemic injury.

Local ischemia and hypoxia are the most important pathological processes in the early phase of secondary spinal cord injury (SCI), in which mitochondria are the main target of ischemic injury. Mitochondrial autophagy, also known as mitophagy, acts as a selective autophagy that specifically identifies and degrades damaged mitochondria, thereby reducing mitochondria-dependent apoptosis. Accumulating evidence shows that the mitophagy receptor, FUN14 domain-containing 1 (FUNDC1), plays an important role in ischemic injury, but the role of FUNDC1 in SCI has not been reported. In this study, we aimed to investigate whether FUNDC1 can enhance mitophagy and inhibit neuronal apoptosis in the early stage of SCI. In a rat SCI model, we found that FUNDC1 overexpression enhanced neuronal autophagy and decreased neuronal apoptosis in the early stage of injury, thereby reducing spinal cord damage. In vitro studies showed that the neuroprotective effects of FUNDC1 were achieved by inhibiting mitochondria-dependent apoptosis and improving mitochondrial function. In addition, FUNDC1 enhanced mitophagy. The protective effects of FUNDC1 against apoptosis and mitochondrial dysfunction were reversed by 3-methyladenine (3-MA), an autophagy inhibitor. Taken together, our results confirm that FUNDC1 can protect against neuronal loss after SCI by inducing mitophagy, inhibiting mitochondria-dependent apoptosis, and improving mitochondrial function.

Epidemiology and clinical presentation of the four human parainfluenza virus types.

BACKGROUND: Human parainfluenza viruses (HPIVs) are important causes of upper respiratory tract illness (URTI) and lower respiratory tract illness (LRTI). To analyse epidemiologic and clinical characteristics of the four types of human parainfluenza viruses (HPIVs), patients with acute respiratory tract illness (ARTI) were studied in Guangzhou, southern China. METHODS: Throat swabs (n=4755) were collected and tested from children and adults with ARTI over a 26-month period, and 4447 of 4755 (93.5%) patients' clinical presentations were recorded for further analysis. RESULTS: Of 4755 patients tested, 178 (3.7%) were positive for HPIV. Ninety-nine (2.1%) samples were positive for HPIV-3, 58 (1.2%) for HPIV-1, 19 (0.4%) for HPIV-2 and 8 (0.2%) for HPIV-4. 160/178 (88.9%) HPIV-positive samples were from paediatric patients younger than 5 years old, but no infant under one month of age was HPIV positive. Seasonal peaks of HPIV-3 and HPIV-1 occurred as autumn turned to winter and summer turned to autumn. HPIV-2 and HPIV-4 were detected less frequently, and their frequency of isolation increased when the frequency of HPIV-3 and HPIV-1 declined. HPIV infection led to a wide spectrum of symptoms, and more "hoarseness" (p=0.015), "abnormal pulmonary breathing sound" (p<0.001), "dyspnoea" (p<0.001), "pneumonia" (p=0.01), and "diarrhoea" (p<0.001) presented in HPIV-positive patients than HPIV-negative patients. 10/10 (100%) HPIV-positive adult patients (≥14 years old) presented with systemic influenza-like symptoms, while 90/164 (54.9%) HPIV-positive paediatric patients (<14 years old) presented with these symptoms (p=0.005). The only significant difference in clinical presentation between HPIV types was "Expectoration" (p<0.001). Co-infections were common, with 33.3%-63.2% of samples positive for the four HPIV types also testing positive for other respiratory pathogens. However, no significant differences were seen in clinical presentation between patients solely infected with HPIV and patients co-infected with HPIV and other respiratory pathogens. CONCLUSIONS: HPIV infection led to a wide spectrum of symptoms, and similar clinical manifestations were found in the patients with four different types of HPIVs. The study suggested pathogenic activity of HPIV in gastrointestinal illness. The clinical presentation of HPIV infection may differ by patient age.

Quantitative cost­effectiveness index of cancer treatments.

In spite of advancements being made in technology and treatment strategies, which have markedly improved the survival rate of patients, the cost of cancer care worldwide has increased over the past decades. The presence of several cost-effectiveness ratios has provided significant indexes to assess the balance between cost and effectiveness. However, the currently available indexes still fail to provide a comprehensive and objective evaluation of cancer treatment. Therefore, the present study developed a novel approach, namely a quantitative cost-effectiveness index of cancer treatment, based on the calculation of the hospitalization expense index and efficacy evaluation index. The present study used the data of 16 patients with childhood acute myeloid leukemia who received the high-dose chemotherapy as an example, and the quantitative cost-effectiveness index was used to evaluate the value of this approach. As the increasing prevalence of cancer and the rising cost of pharmaceuticals have contributed to the expenditure, the development of this index may help to solve the current dilemma of cancer treatment and may prove to be essential for the development of an effective approach which may be accessible to and affordable by common persons; thus would then lead to a higher cure rate.

A novel PRKDC mutation caused B lymphocytes V(D)J rearrangement disorder in the SLE-DAH like symptoms patient.

BACKGROUND: Analyzed the clinical features and treatment process of the patient suffering from immunodeficiency with systemic lupus erythematosus(SLE)-like syndrome in a novel mutation of PRKDC. CASE PRESENTATION: The patient had multiple positive auto-antibodies, chest CT and bronchoscopy showed Diffuse alveolar hemorrhage(DAH), and psychiatric symptoms showed brain atrophy by magnetic resonance imaging (MRI). Whole exon sequencing showed that novel complex heterozygous mutations of PRKDC gene (C. 1777 - 710_1777-709INSA (IVS16/IC16), C.1337T > A(p.Phe446Tyr). The mature B cell (CD19 + CD27 + CD38 dimIgD IgM-) were absent. The treatment of high-dose methylprednisolone (MP) and cyclophosphamide(CTX) can quickly relieve the symptoms of the patient. CONCLUSION: We described the case of an infant immunodeficiency with SLE like-syndrome, which may cause by PRKDC mutation, treated successfully with high-dose MP and CTX.

The effect of therapeutic bronchoalveolar lavage in combination with glucocorticoids on children with acute exogenous lipoid pneumonia.

BACKGROUND: Exogenous lipoid pneumonia (ELP) is a rare disease caused by the inhalation of oily materials in the alveoli with the pathological characterization by the presence of laden-lipid macrophages in the respiratory specimens. At present, the treatment norm for ELP has not well defined, and so the aim of this study is to evaluate the effect of bronchoalveolar lavage in combination with glucocorticoids on children with ELP. METHODS AND MATERIALS: We retrospectively reviewed 17 children with a confirmed history of exogenous oily materials aspiration, admitted to the First Affiliated Hospital of Guangzhou Medical University from June 2012 to December 2021. Clinical features, blood investigations, tomographic evaluations, therapeutic bronchoalveolar lavage and glucocorticoids use were carried out at the beginning of therapy and throughout a follow-up period. RESULTS: The included children are the median age of 2 years. Fever, dypnea and tachypnea were the most common symptoms. The most common radiological features were airspace consolidations (15, 93.75%). Chest CT scans showed areas of consolidation with air bronchogram (15, 93.75%), poorly defined centrilobular nodules (13, 81.25%), areas of ground-glass attenuation (11, 68.75%) and 'crazy-paving' pattern (6, 37.5%) in the both lower, right middle lung lobes. Neutrophil percentage of peripheral blood and bronchoalveolar lavage fluid exhibited a significantly higher than the normal range. After treatment with multiple bronchoalveolar lavages and local administration of budesonide during the hospital stay, taken by oral prednisolone (1 ~ 2 mg/kg) after discharge, all of children became asymptomatic and presented normal radiological imagings in the follow-up period. CONCLUSION: The most frequently findings in the CT scan of ELP were consolidations and ground-glass attenuation in the both lower and right middle lung lobes. Multiple bronchoalveolar lavages in combination with oral prednisolone for children who had a confirmed history of exogenous oily substances ingestion were an efficient and safe for the clearance of oily materials from the lung and the prevention of fibrosis. This strategy contributed to reducing the damage of ELP in children patients.

Epidemiology of respiratory syncytial virus in hospitalized children with community-acquired pneumonia in Guangzhou: a 10-year study.

Background: Respiratory syncytial virus (RSV) is one of the most common virus causing community-acquired pneumonia (CAP) in children. To guide the prevention, diagnosis and treatment of RSV, we aimed to analyze the epidemiology of RSV in hospitalized children with CAP. Methods: A total of 9,837 hospitalized children (≤14 years old) with CAP from January 2010 to December 2019 were reviewed. Using the real-time polymerase chain reaction (RT-PCR), the oropharyngeal swab specimens were collected and tested for RSV, influenza virus A (INFA), influenza virus B (INFB), parainfluenza virus (PIV), enterovirus (EV), coronavirus (CoV), human metapneumovirus (HMPV), human bocavirus (HBoV), human rhinovirus (HRV), and adenovirus (ADV) for each patient. Results: The detection rate of RSV was 15.3% (1,507/9,837). From 2010 to 2019, the RSV detection rate showed a wavy change (χ2=166.982, P<0.001), with the highest detection rate in 2011 (158/636, 24.8%). RSV can be detected throughout the year, with the highest detection rate in February (123/482, 25.5%). Children younger than 0.5 years old had the highest detection rate (410/1,671, 24.5%). The detection rate of RSV in male children (1,024/6,226, 16.4%) was higher than that in female children (483/3,611, 13.4%) (P<0.001). A proportion of 17.7% (266/1,507) of RSV positive cases were also co-infected with other viruses, and INFA (41/266, 15.4%) was the most common coinfection virus. After adjusting for potential confounders, the RSV-positive children were associated with increased risk of severe pneumonia [odds ratio (OR) 1.26, 95% confidence interval (CI): 1.04 to 1.53, P=0.019]. Moreover, children with severe pneumonia had significantly lower cycle threshold (CT) values of RSV than those without severe pneumonia (28.88±3.89 vs. 30.42±3.33, P<0.01). Patients with coinfection (38/266, 14.3%) had a higher risk of severe pneumonia than those without coinfection (142/1,241, 11.4%), but the difference was not statistically significant (OR 1.39, 95% CI: 0.94 to 2.05, P=0.101). Conclusions: The detection rate of RSV in CAP hospitalized children changed by years, months, ages, and sexes. CAP hospitalized children with RSV are more likely to develop severe pneumonia than those without RSV. Policy makers and doctors should make timely adjustments to prevention measures, medical resources and treatment options based on these epidemiological characteristics.

Transcriptome analysis reveals the impact of NETs activation on airway epithelial cell EMT and inflammation in bronchiolitis obliterans.

Bronchiolitis obliterans (BO) is a chronic airway disease that was often indicated by the pathological presentation of narrowed and irreversible airways. However, the molecular mechanisms of BO pathogenesis remain unknown. Although neutrophil extracellular traps (NETs) can contribute to inflammatory disorders, their involvement in BO is unclear. This study aims to identify potential signaling pathways in BO by exploring the correlations between NETs and BO. GSE52761 and GSE137169 datasets were downloaded from gene expression omnibus (GEO) database. A series of bioinformatics analyses such as differential expression analysis, gene ontology (GO), Kyoto encyclopedia of genes and genomes (KEGG), and gene set enrichment analysis (GSEA) were performed on GSE52761 and GSE137169 datasets to identify BO potential signaling pathways. Two different types of BO mouse models were constructed to verify NETs involvements in BO. Additional experiments and bioinformatics analysis using human small airway epithelial cells (SAECs) were also performed to further elucidate differential genes enrichment with their respective signaling pathways in BO. Our study identified 115 differentially expressed genes (DEGs) that were found up-regulated in BO. Pathway enrichment analysis revealed that these genes were primarily involved in inflammatory signaling processes. Besides, we found that neutrophil extracellular traps (NETs) were formed and activated during BO. Our western blot analysis on lung tissue from BO mice further confirmed NETs activation in BO, where neutrophil elastase (NE) and myeloperoxidase (MPO) expression were found significantly elevated. Transcriptomic and bioinformatics analysis of NETs treated-SAECs also revealed that NETs-DEGs were primarily associated through inflammatory and epithelial-to-mesenchymal transition (EMT) -related pathways. Our study provides novel clues towards the understanding of BO pathogenesis, in which NETs contribute to BO pathogenesis through the activation of inflammatory and EMT associated pathways. The completion of our study will provide the basis for potential novel therapeutic targets in BO treatment.

METTL3 Affects Spinal Cord Neuronal Apoptosis by Regulating Bcl-2 m6A Modifications After Spinal Cord Injury.

OBJECTIVE: Spinal cord injury (SCI) is a severe type of neurological trauma. N6-methyladenosine (m6A) modification is one of the most common internal modifications of RNA. The role of METTL3, the predominant methylation enzyme of m6A modification, in SCI remains unclear. This study aimed to investigate the role of methyltransferase METTL3 in SCI. METHODS: After establishing the oxygen-glucose deprivation (OGD) model of PC12 cells and rat spinal cord hemisection model, we found that the expression of METTL3 and the overall m6A modification level were significantly increased in neurons. The m6A modification was identified on B-cell lymphoma 2 (Bcl-2) messenger RNA (mRNA) by bioinformatics analysis, and m6A-RNA immunoprecipitation and RNA immunoprecipitation. In addition, METTL3 was blocked by the specific inhibitor STM2457 and gene knockdown, and then apoptosis levels were measured. RESULTS: In different models, we found that the expression of METTL3 and the overall m6A modification level were significantly increased in neurons. After inducing OGD, inhibition of METTL3 activity or expression increased the mRNA and protein levels of Bcl-2, inhibited neuronal apoptosis, and improved neuronal viability in the spinal cord. CONCLUSION: Inhibition of METTL3 activity or expression can inhibit the apoptosis of spinal cord neurons after SCI through the m6A/Bcl-2 signaling pathway.

Severe pneumonia and pathogenic damage in human airway epithelium caused by Coxsackievirus B4.

Coxsackievirus B4 (CVB4) has one of the highest proportions of fatal outcomes of other enterovirus serotypes. However, the pathogenesis of severe respiratory disease caused by CVB4 infection remains unclear. In this study, 3 of 42 (7.2%, GZ-R6, GZ-R7 and GZ-R8) patients with severe pneumonia tested positive for CVB4 infection in southern China. Three full-length genomes of pneumonia-derived CVB4 were sequenced and annotated for the first time, showing their high nucleotide similarity and clustering within genotype V. To analyze the pathogenic damage caused by CVB4 in the lungs, a well-differentiated human airway epithelium (HAE) was established and infected with the pneumonia-derived CVB4 isolate GZ-R6. The outcome was compared with that of a severe hand-foot-mouth disease (HFMD)-derived CVB4 strain GZ-HFM01. Compared with HFMD-derived CVB4, pneumonia-derived CVB4 caused more intense and rapid disruption of HAE polarity, leading to tight-junction barrier disruption, loss of cilia, and airway epithelial cell hypertrophy. More pneumonia-derived CVB4 were released from the basolateral side of the HAE than HFMD-derived CVB4. Of the 18 cytokines tested, only IL-6 and IL-1b secretion significantly increased on bilateral sides of HAE during the early stage of pneumonia-derived CVB4 infection, while multiple cytokine secretions significantly increased in HFMD-derived CVB4-infected HAE. HFMD-derived CVB4 exhibited stronger neurovirulence in the human neuroblastoma cells SH-SY5Y than pneumonia-derived CVB4, which is consistent with the clinical manifestations of patients infected with these two viruses. This study has increased the depth of our knowledge of severe pneumonia infection caused by CVB4 and will benefit its prevention and treatment.

Identification of Hub Genes in the Pathogenesis of Bronchiolitis Obliterans via Bioinformatic Analysis and Experimental Verification.

Background: Bronchiolitis obliterans (BO) is a chronic disease that can arise as a complication of severe childhood pneumonia and can also impact the long-term survival of patients after lung transplantation. However, the precise molecular mechanism underlying BO remains unclear. We aimed to identify BO-associated hub genes and their molecular mechanisms. Methods: BO-associated transcriptome datasets (GSE52761, GSE137169, and GSE94557) were downloaded from the Gene Expression Omnibus (GEO) database to identify differentially expressed genes (DEGs). Additional bioinformatics analyses, such as Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Protein-Protein Interaction (PPI) analyses, were performed to determine functional roles and DEG-associated regulatory networks. Prediction of hub genes using the 12 algorithms available in the Cytohubba plugin of Cytoscape software was also performed. Verification was performed using the BO mouse model. Results: Our results revealed 57 DEGs associated with BO, of which 18 were down-regulated and 39 were up-regulated. The Cytohubba plugin data further narrowed down the 57 DEGs into 9 prominent hub genes (CCR2, CD1D, GM2A, TFEC, MPEG1, CTSS, GPNMB, BIRC2, and CTSZ). Genes such as CCR2, TFEC, MPEG1, CTSS, and CTSZ were dysregulated in 2,3-butanedione-induced BO mice, whereas TFEC, CTSS, and CTSZ were dysregulated in nitric acid-induced BO mouse models. Conclusion: Our study identified and validated four novel BO biomarkers, which may allow further investigation into the development of distinct BO diagnostic markers and novel therapeutic avenues.