Bronchoscopic characteristics of mycoplasma pneumoniae in children and the level of inflammatory factors in bronchoalveolar lavage fluid / 国际儿科学杂志

Objective To investigate the specpfic electric fiberobronchoscopic manifestations of refractory Mycoplasma pneumoniae pneumonia(RMPP) and explore the level of IL-17,IL-18,PTX3 in bronchoalveolar lavage fluid(BALF) and their clinical sigfinance.Methods To select patients who were diagnosed as MPP and examined by fiberobronchoscopy in acute stage.Dividing them into groups:(1) RMPP group (60cases):dividing RMPP patients into three groups according to if they were treated by systemic corticosteroids or immunoglobulin before the examination of fiberbronchoscope,① RMPP-A group:both are not used.②RMPP-B group:use systemic corticosteroids.③ RMPP-C:both are used.(2)general MPP group(35 cases).15 children with foreign body in bronchus were enrolled as control group.Firstly,to analysis the electric fiberobronchoscopic manifestations of all the cases.Secondly,the cases who had BALF samples in all group were selected,the levels of IL-17,IL-18 and PTX3 are detected by ELISA.Results Under electric fiberobronchoscopy,that the proportions of RMPP group with mucosal erosion,necrotic mucous membrane peeling,sputum bolt blockage in bronchial lumen or moulding are higher than general MPP group.The levels of IL-17,IL-18 and PTX3 in BALF of all MPP cases are higher than control group (P ＜ 0.05),but only the difference of IL-18 between RMPP group and general MPP group has statistical significance (P ＜ 0.05).The levels of IL-17,IL-18 and PTX3 in BALF of RMPP-B group are all higher than RMPP-A group (P ＜ 0.05).Conclusion Mucosal erosion,necrotic mucosa peeling and sputum bolt,moulding are the characteristic manifestations of RMPP,and can help identify RMPP.IL-17,IL-l8 and PTX3 all participated in the pathogenesis of RMPP.Only the level of IL-18 in BALF can be the predictive marker of RMPP.Systemic corticosteroids may inhibit the levels of IL-17,IL-18 and PTX3 of RMPP patients.

Imidacloprid inhibits IgE-mediated RBL-2H3 cell degranulation and passive cutaneous anaphylaxis

BACKGROUND: Imidacloprid has been commonly used as a pesticide for crop protection and acts as nicotinic acetylcholine receptor agonists. Little information about the relationship between imidacloprid and allergy is available. OBJECTIVE: This study aims to examine the effects of imidacoprid on IgE-mediated mast cell activation. METHODS: The rat basophilic leukemia cell line RBL-2H3 (RBL-2H3 cells) were treated with 10⁻³ – 10⁻¹² mol/L imidacloprid, followed by measuring the mediator production, influx of Ca²⁺ in IgE-activated RBL-2H3 cells, and the possible effects of imidacoprid on anti-dinitrophenyl IgE-induced passive cutaneous anaphylaxis (PCA). RESULTS: It was shown that imidacoprid suppressed the production of histamine, β-hexosaminidase, leukotriene C4, interleukin-6, tumor necrosis factor-α, and Ca²⁺ mobilization in IgE-activated RBL-2H3 cells and decreased vascular extravasation in IgE-induced PCA. CONCLUSION: It is the first time to show that imidacloprid suppressed the activation of RBL-2H3 cells.

Receptor for advanced glycation end-products may mediate the upregulation of hypoxia-induced early growth response-1 in mouse aorta / 中华老年医学杂志

Objective To investigate the impact of hypoxia on the expression of early growth response-1 (Egr-1) and monocyte chemoattractant protein-1 (MCP-1) in mouse aorta,and to probe the underlying mechanism involving receptor for advanced glycation end-products (RAGE).Methods 3-month-old C57BL/6 mice were subjected to hypoxia [(6.0±0.5) ％ oxygen] to establish the global hypoxia model(n=6 rats for each).Aortas were dissected,Egr-1 mRNA and MCP-1 mRNA were detected by real time RT-PCR,Egr-1 and RAGE proteins were tested by Western blot,and Egr-1 DNA binding activity was assayed by electrophoretic mobility shift assay (EMSA).For blockade of RAGE,mice were pretreated with soluble RAGE (sRAGE) for 1 h by intra-peritoneal injection before they were exposed to hypoxia.Mice with normoxia were used as controls.Results After 30 minutes of hypoxic exposure,Egr-1 mRNA in aorta was increased to (28.3±0.9)folds compared with normoxic controls (F=617.17,P＜0.01),and the induction persisted for at least 3 hours.After 45 minutes of hypoxic exposure,Egr-1 proteins in aorta was increased to (5.7 ± 0.3) folds compared with normoxic controls (F =57.18,P＜ 0.01); the enhanced DNA binding activity of Egr-1 by hypoxia was attenuated by pretreatment with anti-Egr-1 lgG.After 4 hours of hypoxic exposure,MCP-1 mRNA expression in aorta was increased to(4.0±0.3)folds compared with normoxic controls (F=30.68,P＜0.01).RAGE antigen was increased significantly within 30 minutes of hypoxic exposure,with the peak at 15 minutes; hypoxia-induced Egr-1 mRNA expression was significantly attenuated by pretreatment with sRAGE (3.3 ± 0.2) folds compared with normoxic controls (F =30.20,P＜0.01).Conclusions Hypoxia significantly induces Egr-1 and MCP-1 upregulation expressions in mouse aorta,and blockade of RAGE significantly attenuates hypoxia-induced Egr-1 expression.Thcsc findings suggest RAGE signaling is involved in hypoxia-induced vascular inflammatory stress,and highlight this receptor as a potential therapeutic target to protect tissues injured by hypoxia.

Experimental study of histomorphology and oxidative damage in the liver in senescence accelerated mouse (SAMPS) / 中华老年医学杂志

Objective To evaluate the feasibility of liver senescence model with senescence accelerated mouse prone 8 (SAMP8), and to explore the possible mechanism of oxidative stress in the process of liver aging in SAMP8. Methods Male SAMP8 mice at the age of 9 months were chosen as research objects, and senescence accelerated mouse resistance 1 (SAMR1) mice were used for normal control. Histopathological changes in the liver of SAMR1 and SAMP8 mice were observed by hematoxylin-eosin (HE), Sudan Ⅳ and Masson staining. Senescence associated β-galactosidase activity was measured by histoehemical staining method, and the activities of superoxide dismutase (SOD), eatalase (CAT), glutathione peroxidase (GSH-Px) and the level of malondialdehyde (MDA) in liver homogenate were examined by chemical colorimetry. Results Compared with SAMR1 group, the liver degenerative changes of SAMP8 mice were observed by microscopy, such as extensive fatty degeneration, focal necrosis of hepatocytes and inflammatory cells infiltration. Meanwhile, senescence associated β-galactosidase-positive cells were significantly increased in SAMP8 group [(78.1±11.0) vs.( 23.9±8.8),t=10.887, P<0.01]. In addition, the activities of SOD, CAT and GSH-Px in liver homogenate were decreased [SOD: (214.8 ± 34.8) vs. ( 295.3 ± 29.7), t = 4.975,P<0.01;CAT: (23.0±4.0) vs. ( 36.3±8.3),t=4.084,P<0.01;GSH-Px: (524.0±74.2) vs. (648. 4±102.8) ,t=2. 776, P<0. 05]and the level of MDA was markedly increased ((2.3±0.2) vs. (1.8±0. 1),t = 6. 329, P<0. 01]. Conclusions SAMP8 mice is a feasible animal model for the study of liver senescence, and oxidative stress may play an important role in the process of liver aging in SAMP8.

Expression of mutated insulin gene in HepG-2 cell line / 解放军医学杂志

Objective To express a mutated insulin gene in HepG-2 cell line to further research of insulin gene therapy. Methods Native human insulin cDNA was obtained from fetus pancreas with RT-PCR. Furin consensus cleavage sequence was introduced into proinsulin cDNA with site-directed mutagenesis (overlap extension PCR), and the new sequence was named as INS/furin. Subsequently, INS/furin was subcloned into the multiple clone sites of plasmid p(G1RE)3BP-1Luc. The new plasmid p(G1RE)3BP-11?furin was identified with the method of enzyme digestion by Hind Ⅲ and EcoR V. HepG-2 cells were transfected with the plasmid p(G1RE)3BP-11?furin by liposome-mediated method. The transfected HepG-2 cells were incubated for 48h in a glucose-containing medium (25mmol/L), and then the conditioned media were collected and HepG-2 cells were harvested respectively. The expression of INS/furin mRNA in transfected HepG-2 cells was examined by RT-PCR, the regained DNA was sequenced and insulin in conditioned media was investigated by radioimmunoassay. Results Two enzymes, Hind Ⅲ and EcoR V, digested p(G1RE)3BP-11?furin, and 2 fragments with length of 260 bp and 4 700bp, were obtained. The 260bp fragment was identified as insulin/furin, indicating that the target gene had been successfully inserted in specific sites. RT-PCR showed that insulin/furin mRNA was expressed in transfected HepG-2 cell, and the regained DNA was confirmed as insulin/furin by sequencing; while insulin was detected by radioimmunoassay in conditioned media. Conclusion The recombinant mammalian expression plasmid p(G1RE)3BP-11?furin has been successfully constructed, and transfected into HepG-2 cells, which therefore may efficiently secrete bioactive insulin.