OBJECTIVES:To investigate the protective effects and molecular mechanisms of thymosin β4 (Tβ4) on pyroptosis in BV2 microglial cells. METHODS:BV2 cells were divided into three groups: control group (no treatment), pyroptosis group [stimulated with 1 μg/mL lipopolysaccharide (LPS) for 12 hours, followed by 10 μmol/L nigericin (Nig) treatment for 1 hour], and Tβ4 treatment group (co-incubated with LPS and Nig, then treated with 1 μg/mL Tβ4 for 1 hour). An in vitro sepsis-associated encephalopathy model was established by LPS and Nig co-treatment. Viability of BV2 cells was assessed by CCK-8 assay. RT-qPCR was performed to detect mRNA expression of interleukin (IL)-1β, interferon-induced protein with tetratricopeptide repeats 1 (IFIT1), and interferon-β (IFN-β). IL-1β levels in cell supernatants were measured by ELISA. Protein expression of NLRP3, GSDMD-N, cleaved caspase-1, phosphorylated stimulator of interferon genes (p-STING), and phosphorylated interferon regulatory factor 3 (p-IRF3) was analyzed by Western blot. Cell death rate and mitochondrial reactive oxygen species (ROS) levels were detected by flow cytometry using propidium iodide staining and MitoSOX indicator, respectively. RESULTS:Compared with the pyroptosis group, Tβ4 treatment alleviated morphological damage caused by pyroptosis in BV2 cells. Intracellular mRNA expression of IL-1β, IFIT1, and IFN-β; IL-1β concentration in supernatant; protein expression of NLRP3, GSDMD-N, cleaved caspase-1, p-STING, and p-IRF3; cell death rate; and mitochondrial ROS levels were significantly decreased (P0.05). CONCLUSIONS:Tβ4 protects BV2 microglial cells against LPS and Nig-induced pyroptosis by inhibiting oxidative stress and inflammatory responses, potentially through regulation of the cGAS-STING signaling pathway.
OBJECTIVES:To study the clustering of Streptococcus pneumoniae carriage among school children aged 6-10 years in Haidong City of Qinghai Province, and its influencing factors, providing scientific evidence for preventing and controlling the transmission of Streptococcus pneumoniae in this population. METHODS:Multistage stratified cluster sampling and simple random sampling were used to select 834 healthy children aged 6-10 years from seven kindergartens and five primary schools in Haidong City of Qinghai Province. Oral and nasal swabs were collected for isolation and identification of Streptococcus pneumoniae. Parents completed questionnaire surveys. Data analysis was performed using chi-square tests and random-effects logistic regression models. RESULTS:The carriage rate of Streptococcus pneumoniae was 21.6% (180/834). Cluster analysis showed statistically significant random effects at the school level (Z=2.965, P=0.003; ICC=14.189%). Children aged 8-10 years had a lower carriage rate than those aged 6-7 years (OR=0.467, 95%CI: 0.232-0.938, P=0.032). Children living in households with more than three cohabiting individuals had a higher risk of carriage compared to those with three or fewer (OR=1.541, 95%CI: 1.016-2.339, P=0.042). CONCLUSIONS:Streptococcus pneumoniae carriage among school children aged 6-10 years in Haidong City of Qinghai Province exhibits school-level clustering. Age and number of cohabiting individuals are significant influencing factors for carriage.
Anaphylaxis is a rapid-onset,life-threatening systemic hypersensitivity reaction.Insufficient awareness of this condition in China and delayed or inappropriate use of epinephrine—the core treatment—are major causes of severe outcomes.Based on two clinical cases and the latest domestic and international guidelines,this article systematically describes early recognition and diagnosis of anaphylaxis in children,epinephrine-centered emergency management strategies,and the treatment protocol for refractory anaphylaxis.For classic anaphylaxis,early intramuscular injection of epinephrine into the anterolateral thigh is lifesaving.For refractory anaphylaxis,intravenous continuous infusion of epinephrine should be initiated promptly after two ineffective intramuscular injections,combined with aggressive fluid resuscitation and,if necessary,second-line vasoactive drugs.Antihistamines and corticosteroids are only adjunctive therapies and cannot replace epinephrine.Standardized post-discharge long-term management and the promotion of novel noninvasive delivery routes will further improve prognosis of pediatric anaphylaxis.
OBJECTIVES:To study the clinical features and prognostic impact of CRLF2 overexpression in children with B-cell acute lymphoblastic leukemia (B-ALL). METHODS:A retrospective study included pediatric B-ALL patients admitted to Sichuan Provincial Maternity and Child Health Care Hospital and Kunming Children's Hospital from October 2018 to October 2022. Patients were divided into a CRLF2 overexpression group and a control group without CRLF2 overexpression according to CRLF2 gene testing at initial diagnosis. Clinical features and prognosis between groups were compared. RESULTS:A total of 93 children with B-ALL were enrolled, including 29 with CRLF2 overexpression. The age of onset ranged from 2 to 12 years. At diagnosis, the proportions of hepatosplenomegaly and thrombocytopenia in the CRLF2 overexpression group were significantly lower than those in the control group (P0.05), while the proportion of masses was significantly higher (P0.05). Significantly higher CRLF2 protein expression in the CRLF2 overexpression group than in the control group (P0.05). The mean 3-year event-free survival (EFS) and overall survival (OS) rates in the CRLF2 overexpression group were 75.9% and 85.9%, respectively, lower than the control group (90.1% and 91.0%, respectively), but the differences lacked statistical significance by log-rank test. CONCLUSIONS:These findings suggest a potential role of CRLF2 overexpression in disease progression. Further studies with larger sample sizes are warranted to confirm its prognostic significance.
OBJECTIVES:To investigate the role and mechanism of miR-146b-5p in pulmonary vascular remodeling in neonatal rats with bronchopulmonary dysplasia-associated pulmonary hypertension (BPD-PH) induced by hyperoxia. METHODS:Thirty-two Sprague-Dawley neonatal rats were randomly assigned to normoxia group, BPD-PH group, overexpression group, and inhibitor group (n=8 per group). The normoxia group was raised in 21% oxygen, while the other groups were exposed to 85.0%±0.5% hyperoxia to induce BPD-PH. The overexpression group received tail vein injection of ADV1-miR-146b-5p adenovirus; the inhibitor group received miR-146b-5p inhibitor injections. After 14 days, adenovirus transfection efficiency in lung tissue was confirmed by confocal microscopy. Right ventricular systolic pressure (RVSP) was measured by direct manometry. Right ventricular hypertrophy index (RVHI) was calculated by weighing isolated ventricular tissues. Hematoxylin-eosin staining was used to assess pulmonary vascular morphology, and medial thickness percentage (MT%) and medial area percentage (MA%) of pulmonary vessels were calculated. Mitochondrial ultrastructure of pulmonary vascular endothelial cells was observed by transmission electron microscopy (TEM). Iron deposition in lung tissue was detected by DAB Prussian blue staining and ferrous ion colorimetric assay. Quantitative real-time PCR was used to measure mRNA expression levels of nuclear factor erythroid 2-related factor 2 (Nrf2), glutathione peroxidase 4 (GPX4), solute carrier family 7 member 11 (SLC7A11), and acyl-CoA synthetase long-chain family member 4 (ACSL4). Protein expression levels of these molecules were detected by Western blotting. RESULTS:Compared with the normoxia group, the BPD-PH group showed significantly increased RVSP, RVHI, MT%, and MA% (P0.05), swollen mitochondria, increased iron deposition, downregulated mRNA and protein expression of Nrf2, GPX4, and SLC7A11, and upregulated expression of ACSL4 (P0.05). Compared with the BPD-PH group, the overexpression group exhibited further increases in RVSP, RVHI, MT%, and MA%, severe mitochondrial swelling, significantly elevated iron deposition, decreased Nrf2, GPX4, and SLC7A11 mRNA and protein levels, and increased ACSL4 expression (P0.05). In contrast, the inhibitor group demonstrated decreased RVSP, RVHI, MT%, and MA%, alleviated mitochondrial swelling, reduced iron deposition, upregulated mRNA and protein levels of Nrf2, GPX4, and SLC7A11, and downregulated mRNA and protein levels of ACSL4 (P0.05). CONCLUSIONS:Overexpression of miR-146b-5p promotes pulmonary vascular remodeling in neonatal rats exposed to hyperoxia, likely through inhibition of the Nrf2/GPX4 signaling pathway and regulation of ferroptosis.
