Effects of vasoactive intestinal peptide on airway inflammation and Th17/Treg balance in asthmatic mice / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the effects of vasoactive intestinal peptide (VIP) on the airway inflammation and its regulatory effect on Th17/Treg imbalance in asthmatic mice.</p><p><b>METHODS</b>A total of 30 BALB/c mice were equally and randomly divided into three groups: control, asthma, and VIP. An acute asthmatic mouse model was established by sensitization and challenge with ovalbumin (OVA). The control group received normal saline instead of OVA. Before the challenge with OVA, the VIP group was administered VIP (20 μg/mL) by aerosol inhalation for 30 minutes. The bronchoalveolar lavage fluid (BALF) and the lung tissue were collected from mice. The pathological changes in the lung tissue were observed by hematoxylin and eosin staining. The levels of Th17/Treg-related cytokines in BALF were measured by enzyme-linked immunosorbent assay. The expression of retinoid-related orphan receptor gamma t (RORγt) and forkhead box P3 (Foxp3) were measured by real-time fluorescence quantitative PCR and immunohistochemistry.</p><p><b>RESULTS</b>The histopathological results showed that the VIP group had milder symptoms of airway inflammation than the asthma group. The level of IL-17 in BALF in the asthma group was significantly higher than that in the control group and the VIP group (P<0.01), but the level of IL-17 in the control group was significantly lower than that in the VIP group (P<0.01). The level of IL-10 in BALF in the asthma group was significantly lower than that in the control group and the VIP group (P<0.01, but the level of IL-10 in the VIP group was significantly higher than that in the control group (P<0.01). The asthma group showed significantly higher expression levels of RORγt mRNA and protein in the lung tissue and significantly lower expression levels of Foxp3 mRNA and protein than the control group (P<0.01). The VIP group had significantly lower expression levels of RORγt mRNA and protein in the lung tissue and significantly higher expression levels of Foxp3 mRNA and protein than the asthma group (P<0.05).</p><p><b>CONCLUSIONS</b>The Th17/Treg imbalance may be closely related to the airway inflammation in asthmatic mice. VIP can improve airway inflammation by regulating the Th17/Treg imbalance in asthmatic mice.</p>

Epidemiological characteristics of Mycoplasma pneumoniae pneumonia in children / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To study the epidemiological characteristics of Mycoplasma pneumoniae pneumonia (MPP) in children, and to provide a basis for diagnosis and treatment.</p><p><b>METHODS</b>The serum level of Mycoplasma pneumoniae antibody IgM (MP-IgM) was measured by enzyme-linked immunosorbent assay for 3156 hospitalized children with confirmed community acquired pneumonia from February 2011 to January 2012. The antigens of seven respiratory viruses were detected in the nasopharyngeal secretions of children with MPP.</p><p><b>RESULTS</b>MP-IgM was detected in 427 of the 3156 patients, with a positive rate of 13.53%. The infection rate in female patients was significantly higher than in male patients (16.30% vs 11.70%; P<0.01). The MP-IgM detection rates were 3.6%, 12.5%, 19.2%, and 24.4% in children aged under 1 year, 1-3 years, 3-6 years and 6-14 years respectively (P<0.01), and the total MP-IgM detection rate in children aged under 3 years was significantly lower than in children over 3 years (P<0.01). The MP-IgM detection rate varied with the seasons and was significantly higher in summer and autumn than in winter and spring (19.18% vs 9.61%; P<0.01). Of the 427 MP-IgM-positive children, 60 (14.1%) were infected with respiratory viruses, and the highest proportion of which was respiratory syncytial virus.</p><p><b>CONCLUSIONS</b>MPP is sporadic throughout the whole year, with a higher incidence in summer and autumn. MPP occurs mostly in preschool and school-age children, and there is mixed infection of MP and respiratory viruses.</p>