[Application of metagenomic next-generation sequencing technology in preterm infants with sepsis following antibiotic use]. / å®åŸºå› ç»„äºŒä»£æµ‹åºæŠ€æœ¯åœ¨æŠ—ç”Ÿç´ ä½¿ç”¨åŽçš„æ—©äº§å„¿è´¥è¡€ç—‡ä¸­çš„åº”ç”¨.

OBJECTIVES: To explore the value of metagenomic next-generation sequencing (mNGS) technology in the etiological diagnosis of sepsis in preterm infants following antibiotic use. METHODS: A retrospective analysis of medical records for 45 preterm infants with sepsis who were treated at Henan Provincial People's Hospital. All patients received antibiotic treatment for ≥3 days and underwent both blood culture and mNGS testing. The detection rates of pathogens by blood culture and mNGS testing were compared. RESULTS: The positive detection rate of pathogens by blood mNGS was higher than that by blood culture (44% vs 4%; P<0.001). Blood mNGS detected 28 strains of pathogens, including 23 bacteria, 4 fungi, and 1 Ureaplasma parvum. Blood culture identified one case each of Rhodotorula mucilaginosa and Klebsiella pneumoniae. In the group treated with antibiotics for >10 days, the positive rate of blood mNGS testing was higher than that of blood culture (40% vs 3%; P<0.001); similarly, in the group treated with antibiotics for ≤10 days, the positive rate of blood mNGS testing was also higher than that of blood culture (53% vs 7%; P=0.020). Treatment plans were adjusted based on blood mNGS results for 13 patients, with an effectiveness rate of 85% (11/13). CONCLUSIONS: In preterm infants with sepsis following antibiotic use, the positive rate of pathogen detection by blood mNGS is higher than that by blood culture and is unaffected by the duration of antibiotic use. Therefore, mNGS testing can be considered for confirming pathogens when clinical suspicion of infection is high but blood culture fails to detect the pathogen.

Psychological status of parents of hospitalized children during the COVID-19 epidemic in China.

A series of unexplained pneumonia appeared in Wuhan, Hubei Province, China, which is highly contagious. The virus is prone to nervous and anxious psychological reactions. In the objective environment of complex and densely populated hospitals, it is a high-risk area for virus-transmitted infections and children generally have lower immunity who are more likely to develop infections. The results showed that the mental health problems of parents of hospitalized children during the epidemic were more serious, and the anxiety and depression were more obvious.

[Effect of montelukast sodium intervention on airway remodeling and percentage of Th17 cells/CD4+CD25+ regulatory T cells in asthmatic mice].

OBJECTIVE: To study the dynamic changes in the percentage of Th17 cells/CD4+CD25+ regulatory T cells after intervention with montelukast sodium, a leukotriene receptor antagonist, in asthmatic mice and the association between them. METHODS: Balb/c mice were randomly divided into blank group, asthma group, and montelukast sodium group. The asthmatic mouse model of airway remodeling was established by sensitization with intraperitoneal injection of chicken ovalbumin (OVA) and aluminum hydroxide suspension and aerosol inhalation of OVA. The mice in the blank group were given normal saline, and those in the montelukast sodium group were given montelukast sodium by gavage before aerosol inhalation. Eight mice were randomly sacrificed within 24 hours after 2, 4, and 8 weeks of aerosol inhalation. The pathological sections of lung tissue were used to observe the degree of airway remodeling. Flow cytometry was used to measure the percentages of Th17 cells and CD4+CD25+ regulatory T cells in CD4+ T cells. RESULTS: The asthma group and the montelukast sodium group had significantly higher bronchial wall thickness and smooth muscle thickness at all time points compared with the blank group (P<0.05). At 8 weeks of intervention, the montelukast sodium group had significantly greater improvements in the above changes compared with the asthma group (P<0.05). Compared with the blank group, the asthma group and the montelukast sodium group had significant increases in Th17 cells (positively correlated with airway remodeling) and significant reductions in CD4+CD25+ regulatory T cells (negatively correlated to airway remodeling) at all time points (P<0.05). At 8 weeks of intervention, the montelukast sodium group had a significant reduction in the number of Th17 cells and a significant increase in the number of CD4+CD25+ regulatory T cells compared with the asthma group (P<0.05). CONCLUSIONS: Montelukast sodium intervention can alleviate airway remodeling and achieve better improvements over the time of intervention. The possible mechanism may be related to the improvement of immunologic derangement of CD4+CD25+ regulatory T cells and inhibition of airway inflammation.

[Dynamic changes in percentages of CD4⁺ CD25⁺ regulatory T cells and Th17 cells in process of airway remodeling in mouse model of asthma].

OBJECTIVE: To study the dynamic changes in Th17 cells and CD4⁺ CD25⁺ regulatory T cells (Treg) in the spleen and to analyze their relationship with airway remodeling. METHODS: A total of 48 female specific pathogen-free Balb/c mice were randomly divided into control and asthmatic groups. To establish the asthmatic airway remodeling model, the mice were sensitized to ovalbumin (OVA) through intraperitoneal injection of OVA and aluminum hydroxide suspension and challenged by inhalation of aerosol OVA. The matched control group was treated with normal saline instead. In 24 hours after 2-week, 4-week, and 8-week aerosol inhalation, 8 mice were randomly selected from each group and sacrificed. Then histopathological examination of the left lung was performed to measure the degree of airway remodeling. The percentages of Th17 and CD4⁺ CD25⁺ Treg cells in total CD4(+) cells from the spleen were determined by flow cytometry. RESULTS: In the asthmatic group, the ratios of total bronchial wall area to bronchial basement membrane perimeter (WAt/Pbm) and bronchial smooth muscle area to bronchial basement membrane perimeter (WAm/Pbm) significantly increased as the challenge proceeds (P<0.01). The percentage of Th17 cells derived from the cell suspension of the spleen gradually increased and it was positively correlated with the degree of asthmatic airway remodeling (P<0.01). The percentage of CD4⁺ CD25⁺ Treg cells from the suspension gradually decreased and it was negatively correlated with the degree of asthmatic airway remodeling (P<0.01). CONCLUSIONS: In mice with asthma, as the challenge proceeds, the airway remodeling becomes more severe, the percentage of Th17 cells increases, and the percentage of CD4⁺ CD25⁺ Treg cells decreases. The immunological imbalance is possibly one of the important factors inducing airway remodeling.