ABSTRACT
Objective:To investigate the related mechanism of IL-17B in regulating host immune response by studying the role and mechanism of IL-17B in the infection of Listeria monocytogenes in mice. Methods:Eighteen male C57BL/6 mice were randomly divided into three groups with six in each group: control group, PBS group and wild-type (WT) group. The control group was not given any treatment. The mice in the PBS group were injected with 100 μl of sterile PBS, while C57BL/6 mice in the WT group and IL-17B deficient (IL-17B -/-) male mice were injected intravenously with 100 μl of Listeria monocytogenes 19115 (2×10 4 colony forming unit). The mice were sacrificed 48 h after infection and then peripheral blood, spleen and liver samples were collected. Bacterial colonization in mouse spleen and liver was detected by plate count method; HE staining was used to evaluate histopathological damages; flow cytometry was used to detect the immune cells in different tissues. ELISA and qRT-PCR were used to detect the levels of IL-1β, IL-6, IL-12p40, TNF-α, IFN-γ and iNOS in serum and spleen. qRT-PCR were used to detect the expression of IL-17B and IL-17RB. Results:Bacterial colonization in mouse spleen was reduced in the IL-17B -/- group as compared with that in the WT group ( P<0.05). Compared with the PBS group, Listeria monocytogenes infection increased the expression of IL-17B and IL-17RB in mouse spleen ( P<0.05, P<0.01). There was no significant difference in the pathological damages in spleen between WT and IL-17B -/- groups. Moreover, compared with the WT group, the IL-17B -/- group showed increased macrophages, M1 macrophages ( P<0.01) and NK cells ( P<0.05) in spleen, up-regulated macrophages ( P<0.05) and M1 macrophages ( P<0.01) in the peripheral blood, enhanced expression of IL-6 in serum and spleen ( P<0.05), and promoted expression of IL-6, IL-12, IL-1β, TNF-α, IFN-γ and iNOS in spleen. Conclusions:IL-17B might inhibit Listeria monocytogenes clearance by inhibiting macrophage infiltration and the secretion of IL-6.
ABSTRACT
Objective:To explore the application value of 256-layer spiral CT left atrial pulmonary vein dual phase scanning imaging (called simply CT dual phase scanning imaging) in radiofrequency ablation of nonvalvular atrial fibrillation.Methods:The clinical data of 74 patients with nonvalvular atrial fibrillation from October 2018 to September 2020 in Tiantan Hospital, Capital Medical University were retrospectively analyzed. All patients were examined by CT dual phase scanning imaging and transesophageal echocardiography (TEE). The result of TEE was as "gold standard", the value of CT dual phase scanning imaging in the diagnosis of left atrial pre-thrombotic state (PTS) and thrombus were assessed, and the variation of the pulmonary vein was observed.Results:CT dual phase scanning imaging in diagnosis of left atrial PTS had a sensitivity of 52.94% (9/17), a specificity of 92.45%(49/53), a negative predictive value of 85.96%(49/57), and a positive predictive value of 69.23%(9/13); it in diagnosis of left atrial thrombus had a sensitivity of 100.00% (4/4), a specificity of 90.74%(49/54), a negative predictive value of 100.00%(49/49), and a positive predictive value of 44.44%(4/9). The variation rate of the pulmonary vein was 21.62%(16/74).Conclusions:CT dual phase scanning imaging has relatively high values of sensitivity, specificity and negative predictive value in detecting left atrial PTS and thrombus. It can also evaluate the abnormal anatomical characteristics of the pulmonary vein, and find pulmonary vein variation. It provides a reliable basis for radiofrequency ablation of nonvalvular atrial fibrillation.