Association of DNA methylation/demethylation with the functional outcome of stroke in a hyperinflammatory state

Inflammation is closely related to stroke prognosis, and high inflammation status leads to poor functional outcome in stroke. DNA methylation is involved in the pathogenesis and prognosis of stroke. However, the effect of DNA methylation on stroke at high levels of inflammation is unclear. In this study, we constructed a hyperinflammatory cerebral ischemia mouse model and investigated the effect of hypomethylation and hypermethylation on the functional outcome. We constructed a mouse model of transient middle cerebral artery occlusion and treated the mice with lipopolysaccharide to induce a hyperinflammatory state. To investigate the effect of DNA methylation on stroke, we used small molecule inhibitors to restrain the function of key DNA methylation and demethylation enzymes. 2,3,5-Triphenyltetrazolium chloride staining, neurological function scores, neurobehavioral tests, enzyme-linked immunosorbent assay, quantitative reverse transcription PCR and western blot assay were used to evaluate the effects after stroke in mice. We assessed changes in the global methylation status by measuring DNA 5-mc and DNA 5-hmc levels in peripheral blood after the use of the inhibitor. In the group treated with the DNA methylation inhibitor, brain tissue 2,3,5-triphenyltetrazolium chloride staining showed an increase in infarct volume, which was accompanied by a decrease in neurological scores and worsening of neurobehavioral performance. The levels of inflammatory factors interleukin 6 and interleukin-1 beta in ischemic brain tissue and plasma were elevated, indicating increased inflammation. Related inflammatory pathway exploration showed significant overactivation of nuclear factor kappa B. These results suggested that inhibiting DNA methylation led to poor functional outcome in mice with high inflammation following stroke. Further, the effects were reversed by inhibition of DNA demethylation. Our findings suggest that DNA methylation regulates the inflammatory response in stroke and has an important role in the functional outcome of hyperinflammatory stroke.

学科领域知识中程序性知识水平对中学生数学问题表征策略的影响

采用2 ×4两因素试验设计,探讨学科领域知识中程序性知识水平对中学生问题表征的影响。先用程序性知识水平测量问卷挑选出60名中学生参加实验,将其分为两组。然后采用学习–干扰–测验研究范式,以四类算式为研究材料,研究程序性知识水平对中学生问题表征策略的影响。结果表明:低程序性知识水平与高程序性知识水平的学生在问题表征时都使用直接转换策略和问题模型策略;低程序性知识水平学生倾向于采用直接转换策略;高程序性知识水平学生倾向于采用问题模型策略。

Pathogens of first-episode pulmonary infection in 141 children with chronic granulomatous disease

To the Editor:Chronic granulomatous disease(CGD)is an inherited primary immunodeficiency disease characterized by recurrent life-threatening bacterial or fungal infection and tissue granuloma formation.^([1])Pulmonary infection is the most frequent manifestation,affecting nearly 80%of patients,[2]and remains the major cause of morbidity and mortality in patients with CGD.Details of the pathogenic microorganisms responsible for first-episode pulmonary infection provide information on the spectrum of infection in patients with CGD,help guide the empirical choice of antibiotics or antifungal therapy,and contribute to the early identification and management of CGD.Aspergillus is the commonest causative agent of pulmonary infection,but the distribution of other pathogens varies among countries.^([2–5])Few studies have investigated the etiology of pulmonary infection in CGD in a large cohort in China.

脑出血患者静脉血栓栓塞机械预防的证据总结

目的检索、评价和整合脑出血患者静脉血栓栓塞机械预防的相关证据,为降低脑出血患者静脉血栓栓塞的发生率提供参考。方法应用循证护理的方法,针对脑出血患者静脉血栓栓塞的机械预防提出问题、检索相关文献、采用澳大利亚Joanna Briggs Institute循证卫生保健中心的文献评价标准和证据分级系统,对各类研究进行文献质量评价及证据级别评定。结果从机械装置选择、机械预防方法、机械预防时间、机械预防禁忌证和病情观察要点等方面共总结出16条最佳证据。结论脑出血患者静脉血栓栓塞机械预防的证据总结过程科学,总结的证据实用性强,临床护士可以通过应用最佳证据预防静脉血栓栓塞,提升护理质量。

Proteomics study of Mycoplasma pneumoniae pneumonia reveals the Fc fragment of the IgG-binding protein as a serum biomarker and implicates potential therapeutic targets

Macrolide and corticosteroid resistance has been reported in patients with Mycoplasma pneumoniae(MP)pneumonia(MPP).MP clearance is difficult to achieve through antibiotic treatment in sensitive patients with severe MPP(SMPP).SMPP in children might progress to airway remodeling and even bronchiolitis/bronchitis obliterans.Therefore,identifying serum biomarkers that indicate MPP progression and exploring new targeted drugs for SMPP treatment require urgency.In this study,serum samples were collected from patients with general MPP(GMPP)and SMPP to conduct proteomics profiling.The Fc fragment of the IgG-binding protein(FCGBP)was identified as the most promising indicator of SMPP.Biological enrichment analysis indicated uncontrolled inflammation in SMPP.ELISA results proved that the FCGBP level in patients with SMPP was substantially higher than that in patients with GMPP.Furthermore,the FCGBP levels showed a decreasing trend in patients with GMPP but the opposite trend in patients with SMPP during disease progression.Connectivity map analyses identified 25 possible targeted drugs for SMPP treatment.Among them,a mechanistic target of rapamycin kinase(mTOR)inhibitor,which is a macrolide compound and a cell proliferation inhibitor,was the most promising candidate for targeting SMPP.To our knowledge,this study was the first proteomics-based characterization of patients with SMPP and GMPP.

The value of nasal nitric oxide measurement in the diagnosis of primary ciliary dyskinesia

Importance:Nasal nitric oxide(nNO)testing is a method used in the diagnosis of primary ciliary dyskinesia(PCD).It has not been evaluated in Chinese population.Objective:To establish a reference nNO value to assist in the diagnosis of PCD in Chinese children.Methods:nNO values were measured in children with PCD(n=36),cystic fibrosis(CF)(n=20),asthma(n=45),post-infectious bronchiolitis obliterans(BO)(n=41)and non-PCD/non-CF bronchiectasis(n=32).The receiver operating characteristic nNO value for the diagnosis of PCD was plotted and the area under the curve was calculated.Results:nNO values were significantly lower in children with PCD(median 25.66 nL/min)than in children with asthma(186.26±58.95 nL/min),BO(143.47±49.71 nL/min)and non-PCD/non-CF bronchiectasis(173.13±63.80 nL/min),but not in children with CF(90.90±43.20 nL/min).Notably however,no CF patient had an nNO value<45 nL/min.A cut-offof 76 nL/min yielded the best sensitivity of 86.1%,and specificity of 91.4%,with an area under the curve of 0.920(95%confidence interval 0.859-0.981)for the diagnosis of PCD.If CF was ruled out the specificity increased to nearly 100%.Interpretation:nNO testing is able to discriminate between patients with PCD and those with CF,asthma,post-infectious BO and non-PCD/non-CF bronchiectasis.A cut-off of 76 nL/min could be further examined in patients suspected of PCD,to establish an nNO reference value for PCD screening in Chinese children.

Surfactant protein C dysfunction with new clinical insights for diffuse alveolar hemorrhage and autoimmunity

Importance:Surfactant protein C(SP-C)dysfunction is a rare disease associated with interstitial lung disease.Early therapies may improve outcomes but the diagnosis is often delayed owing to variability of manifestations.Objective:To investigate the manifestations and outcomes of SP-C dysfunction.Methods:We retrospectively analyzed the records of five pediatric patients who were diagnosed with SP-C dysfunction between February 2014 and April 2017 at Beijing Children's Hospital.Results:The five patients included two boys and three girls with a median age at diagnosis of 1.3 years.All patients presented with interstitial lung disease and had a heterozygous SFTPC mutation,including an I73T mutation in three patients,a V39L mutation in one patient,and a Y 104H mutation in one patient.In addition to common respiratory manifestations,hemoptysis and anemia were observed in one patient with the I73T mutation.Elevated levels of autoantibodies and a large number of hemosiderin-laden macrophages in bronchoalveolar lavage fluid were found in two patients with the I73T mutation,suggesting the presence of diffuse alveolar hemorrage and autoimmunity.Chest high-resolution computed tomography features included ground-glass opacities,reticular opacities,cysts,and pleural thickening.Transbronchial lung biopsy was performed in one patient with the I73T mutation,which revealed the presence of some hemosiderin-laden macrophages in alveolar spaces.All patients received treatment with corticosteroids;two received combined treatment with hydroxychloroquine.During follow-up,the two patients who received hydroxychloroquine showed improved symptoms;of the remaining three patients,two died after their families refused further treatment,while the final patient was lost to follow-up.Interpretation:This is the first report to describe a new phenotype of diffuse alveolar hemorrhage with autoimmunity in patients with I73T SFTPC mutation.Treatment with hydroxychloroquine should be considered for patients with SP-C dysfunction.

Galectin-7 overexpression destroys airway epithelial barrier in transgenic mice

When the integrity of airway epithelium is destroyed,the ordered airway barrier no longer exists and increases sensitivity to viral infections and allergens,leading to the occurrence of airway inflammation such as asthma.Here,we found that galectin-7 transgenic(+)mice exhibited abnormal airway structures as embryos and after birth.These abnormalities included absent or substantially reduced pseudostratified columnar ciliated epithelium and increased monolayer cells with irregular arrangement and widening of intercellular spaces.Moreover,airway tissue from galectin-7 transgenic(+)mice showed evidence of impaired cell–cell junctions and decreased expression of zonula occludens-1(ZO-1)and E-cadherin.When treated with respiratory syncytial virus(RSV)or ovalbumin(OVA),galectin-7 transgenic(+)mice developed substantially increased bronchial epithelial detachment and apoptosis,airway smooth muscle and basement membrane thickening,and enhanced airway responsiveness.We found that Galectin-7 localized in the cytoplasm and nucleus of bronchial epithelial cells,and that increased apoptosis was mediated through mitochondrial release of cytochrome c and upregulated JNK1 activation and expression of caspase-3 in galectin-7 Tg(+)mice.These findings suggested that Galectin-7 causes airway structural defects and destroys airway epithelium barrier,which predispose the airways to RSV or OVA-induced epithelial apoptosis,injury,and other asthma responses.

Clinical significance of interventional therapeutic bronchoscopy combined with bronchial arterial embolization in the treatment of hypervascular primary airway tumors in children

Importance Pediatric hypervascular primary airway tumors are progressive,fatal lesions with a low incidence,and the disease is often more serious than that in adults.Objective To evaluate the clinical efficacy and safety of interventional therapeutic bronchoscopy combined with conservative treatment and bronchial arterial embolization in children with primary airway tumors.Methods We retrospectively analyzed the clinical data of four pediatric patients with hypervascular primary airway tumor between 2017 and 2019 at Beijing Children’s Hospital.Results Two patients were low-grade bronchial mucoepidermoid carcinoma,one patient was pleomorphic adenoma,and one was bronchial leiomyoma.Interventional therapeutic bronchoscopy combined with bronchial arterial embolization was used for treatment(all four patients received general anesthesia).The tumors were safely resected in all patients via interventional bronchoscopy.There were no severe complications related to the procedures.All patients were followed up for 5–12 months,and one low-grade bronchial mucoepidermoid carcinoma recurred.Interpretation Interventional therapeutic bronchoscopy combined with bronchial arterial embolization appears to be a safe and efficient therapeutic method associated with less trauma and fewer complications,including no serious adverse events,in children with hypervascular primary airway tumors without bronchus wall infiltration.

Clinicoradiologic features of Mycoplasma pneumoniae bronchiolitis in children

Importance: Acute Mycoplasma pneumoniae bronchiolitis can progress into bronchiolitis obliterans (BO) in children, which has a major influence on a child's quality of life and is associated with M. pneumoniae bronchiolitis. Early identification and treatment of M. pneumoniae bronchiolitis is important to prevent the development of BO. Objective: To enhance the understanding of the diagnosis and treatment of M. pneumoniae bronchiolitis in children. Methods: Eight patients with M. pneumoniae bronchiolitis were retrospectively analyzed. results: Five of the patients with M. pneumoniae bronchiolitis were male and three of them were female. All patients suffered from fever and cough. Moist rales and wheezing were noted in both lungs in six patients. High-resolution computed tomography of the chest showed bronchiolitis in all patients, with large airway injury in two and focal bronchopneumonia in six. Two patients were confirmed to have asthma. Seven patients had personal and/or family histories of atopic diseases. Allergen testing was performed in six patients, which produced positive results in four;the remaining two patients had negative results, but their total IgE levels were > 200 IU/ml. Azithromycin therapy and glucocorticoid therapy was administered to all eight patients. One patient required noninvasive ventilation. Treatment of all patients was successful, with no development of bronchiolitis obliterans during the 4- to 8-month follow-up. Interpretation: Mycoplasma pneumoniae bronchiolitis can occur in children, especially in atopic individuals. The use, time of initiation, and effects of glucocorticoids administration in these patients for the prevention of BO require further investigation.

Pandemic 2009 influenza A(H1N1)-associated deaths among children in China:A retrospective analysis

Importance:A cluster of influenza-associated deaths occurred among children during pandemic 2009 influenza A(H 1N1)in China,but the risk factors and causes for death have not been clarified.Objective:We describe the clinical findings regarding 2009 influenza A(H1N1)-associated pediatric deaths in China,including the risk factors for death.Methods:The definition of 2009 influenza A(H1N1)-associated pediatric death is death in a child who is younger than 14 years and has laboratory-confirmed influenza.We collected data of total 810 hospitalized patients with 2009 influenza A(H 1N 1)infection from September 2009 to February 2010 in 17 hospitals across China.The clinical characteristics,laboratory abnormalities,and treatment course were retrospectively studied.Results:Of the 810 patients hospitalized with 2009 influenza A(H1N1)infection,19(2.3%)died.Ten patients died from severe pneumonia and acute respiratory distress syndrome;eight died from encephalopathy/encephalitis;one died from secondary fungal meningitis.Patients who died were more likely than patients who survived to have neutrophilia,lymphopenia,elevated C-reactive protein,and elevations of lactate dehydrogenase,creatine kinase,creatine kinase-MB,aspartate aminotransferase and alanine aminotransferase.There were no significant differences in the median age,median time from onset of illness to admission,underlying chronic disease,and initiation of antiviral therapy within 48 hours of illness onset,between patients who died and those who survived.Interpretation:The risk factors for pediatric death associated with 2009 influenza A(H 1N 1)infection are different from those of seasonal influenza.The most common causes of death are viral pneumonia,acute respiratory distress syndrome,and encephalopathy/encephalitis.

Bacteremia tuberculosis among HIV-negative children in China

Importance:Bacteremia tuberculosis(TB)is a severe form of extrapulmonary TB.Studies assessing bacteremia TB in children are limited,especially for HIV-negative children.Objective:To explore the detailed clinical features of the bacteremia TB in children under 18 years of age.Methods:We reviewed the clinical records of the patients retrospectively and collected the strains isolated from their blood cultures.We used mycobacterial interspersed repetitive-unit-variable-number tandem-repeat(MIRU-VNTR)to characterize the bacterial genotypes and alamarBlue to determine their drug susceptibility profiles.Polymerase chain reactions and DNA sequencing were used to identify drug-resistant mutations.Results:There were 13 pediatric bacteremia TB patients,10 of whom were diagnosed with Bacillus Calmette–Guérin(BCG)bacteremia TB.Thirteen patients aged from 0.30 to 11.58 years were enrolled,of whom 76.92%were boys.All had fevers before hospitalization,and 76.92%had respiratory symptoms.All had received BCG vaccinations,and 46.15%had adverse post-vaccination reactions.Compared withMycobacterium tuberculosis,BCG bacteremia was more likely to appear in younger children.Patients with BCG bacteremia had primary immunodeficiency diseases,and lower CD4,IgA,and IgE levels.Interpretation:Bacteremia TB was rapidly fatal in a large proportion of the immunodeficient children.Because classic findings may not be diagnostically specific,a high level of clinical suspicion is required,especially for patients with certain types of immunosuppression.Studies are needed to develop rapid diagnostic tests and to determine the value of empirical therapy in childhood bacteremia TB.