OBJECTIVE To explore the distribution and drug resistance of pathogens isolated from the children with recurrent respiratory tract infection(RRI)and analyze the expressions of Toll-like receptors(TLRs)in peripheral blood mononuclear cells(PBMCs)so as to provide bases for the diagnosis.METHODS A total of 52 children with RRI who were treated in Hainan Modern Women and Children's Hospital from Oct.2021 to Oct.2023 were re-cruited as the case group,meanwhile,61 healthy children who received physical examination were chosen as the healthy group.The distribution and drug resistance of the pathogens isolated from the case group were statistically analyzed.The levels of PBMCs TLR2 and TLR4 were compared between the two groups.The values of TLR2 and TLR4 in diagnosis of the children with RRI were analyzed by means of receiver operating characteristic(ROC)curves.RESULTS Totally 311 strains of pathogens were isolated from the 52 children with RRI,among which gram-negative bacteria were dominant;Haemophilus influenzae was the major species of gram-negative bacteria,and Staphylococcus aureus was the predominant species of gram-positive bacteria.The H.influenzae strains were mainly resistant to ceftazidime,cefepime and gentamycin,but were sensitive to imipenem and meropenem.The S.aureus strains were highly resistant to penicillin and ampicillin,but were sensitive to vancomycin and nitrofuran-toin.There were significant differences in the levels of PBMCs TLR2 and TLR4 between the case group and the healthy group(P＜0.05).The area under the curve(AUC)value of the joint detection of TLR2 and TLR4 was higher than that of the single detection in diagnosis of the children with RRI(P＜0.05),the sensitivity of the joint detection was 76.92％,with the specificity 95.08％.CONCLUSIONS The gram-negative bacteria are dominant a-mong the pathogens isolated from the children with RRI.Imipenem and meropenem are recommended for the treatment of H.influenzae infection;vancomycin and nitrofurantoin are recommended for treatment of S.aureus infection.The children with RRI show the abnormal expressions of TLRs in PBMCs.The joint detection of TLR2 and TLR4 can raise the diagnostic value of the RRI children.

OBJECTIVE To explore the distribution and drug resistance of pathogens isolated from the children with recurrent respiratory tract infection(RRI)and analyze the expressions of Toll-like receptors(TLRs)in peripheral blood mononuclear cells(PBMCs)so as to provide bases for the diagnosis.METHODS A total of 52 children with RRI who were treated in Hainan Modern Women and Children's Hospital from Oct.2021 to Oct.2023 were re-cruited as the case group,meanwhile,61 healthy children who received physical examination were chosen as the healthy group.The distribution and drug resistance of the pathogens isolated from the case group were statistically analyzed.The levels of PBMCs TLR2 and TLR4 were compared between the two groups.The values of TLR2 and TLR4 in diagnosis of the children with RRI were analyzed by means of receiver operating characteristic(ROC)curves.RESULTS Totally 311 strains of pathogens were isolated from the 52 children with RRI,among which gram-negative bacteria were dominant;Haemophilus influenzae was the major species of gram-negative bacteria,and Staphylococcus aureus was the predominant species of gram-positive bacteria.The H.influenzae strains were mainly resistant to ceftazidime,cefepime and gentamycin,but were sensitive to imipenem and meropenem.The S.aureus strains were highly resistant to penicillin and ampicillin,but were sensitive to vancomycin and nitrofuran-toin.There were significant differences in the levels of PBMCs TLR2 and TLR4 between the case group and the healthy group(P＜0.05).The area under the curve(AUC)value of the joint detection of TLR2 and TLR4 was higher than that of the single detection in diagnosis of the children with RRI(P＜0.05),the sensitivity of the joint detection was 76.92％,with the specificity 95.08％.CONCLUSIONS The gram-negative bacteria are dominant a-mong the pathogens isolated from the children with RRI.Imipenem and meropenem are recommended for the treatment of H.influenzae infection;vancomycin and nitrofurantoin are recommended for treatment of S.aureus infection.The children with RRI show the abnormal expressions of TLRs in PBMCs.The joint detection of TLR2 and TLR4 can raise the diagnostic value of the RRI children.

Periodontitis is the inflammation of periodontal tissue caused by dental plaque, which absorbs the alveolar bone and cementum. The immune response triggered by CD4+T cells is the key factor for the aggravation of periodontitis. The activation of dendritic cells and the receptor activator of the NF-κB ligand (RANKL) pathway is an important link in the alveolar bone resorption of periodontal tissue. Pro-inflammatory factors such as interferon-γ (IFN-γ), tumor necrosis factor (TNF-α) and interleukin-1β (IL-1β) also play important roles in the development of periodontitis. Interleukin-37(IL-37), which is a newly discovered cytokine in the IL-1 family, has five shear variants from a to e, among which the clover β-structure encoded by exon 4 plays an important role in the binding of cytokines and the corresponding receptors. IL-37 has strong anti-inflammatory and inhibition of autoimmunity, can enter the nucleus with the help of caspase-1 and bind with Smad proteins to regulate the transcription of pro-inflammatory genes. Extracellular IL-37 can bind to IL-18 binding protein and inhibit the production of pro-inflammatory factors. IL-37 can inhibit the progression of periodontitis by inhibiting the RANKL signaling pathway, inhibiting the proliferation and differentiation of dendritic cells and CD4+T cells, binding to Smad proteins, and releasing pro-inflammatory factors such as IFN-γ and TNF-α. The IL-37 concentration in periodontal tissue can indicate the progression of periodontitis. Few studies have described the interaction between the anti-inflammatory factor IL-37 and periodontitis. Thus, in this paper, the structure and function of IL-37 and the related factors between IL-37 and periodontitis will be reviewed.