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81.
C. Ahlström-Emanuelsson M. Andersson C. Persson† C. Schrewelius‡ L. Greiff 《Clinical and experimental allergy》2004,34(5):731-735
BACKGROUND: Rofleponide palmitate is an esterified glucocorticosteroid pro-drug with a promising pre-clinical profile designed to deliver topical airway treatment for allergic rhinitis and asthma in a novel manner. Thus, the rofleponide palmitate pro-drug is designed to provide topical exposure of the mucosa to the inactive lipophilic drug, which would be locally metabolized to the more hydrophilic and readily cleared drug rofleponide. OBJECTIVE: To examine whether rofleponide palmitate affects nasal symptoms and peak inspiratory flow (PIF) in a pollen-season model of allergic rhinitis and to compare any such effects with those of another glucocorticosteroid (i.e., budesonide). METHODS: During the pollen-free season, 40 patients with strictly seasonal allergic rhinitis received topical nasal spray treatment with an aqueous solution of rofleponide palmitate 400 microg and an aqueous solution of budesonide 128 microg once daily for 10 days in a double-blind, placebo-controlled, and crossover study. After 3 days of drug treatment, individualized allergen challenges were given once daily for 7 days while the treatment continued. The washout periods between each of the challenge series were 2 weeks. Nasal symptoms and PIF were recorded in the morning and evening, as well as 10 and 20 min after each allergen challenge. The mean recordings obtained during the last 3 days of the allergen-challenge series, when symptoms were established and when the treatment had lasted for 8-10 days, were used in the analysis. RESULTS: Both active treatments reduced nasal symptoms and improved nasal PIF compared with placebo (P<0.01-0.001). There was no overall difference in efficacy between rofleponide palmitate 400 microg and budesonide 128 microg. CONCLUSIONS: Topical treatment with aqueous solutions of rofleponide palmitate attenuates nasal symptoms and improves nasal PIF in allergic rhinitis. The overall efficacy of 400 microg of rofleponide palmitate is similar to that of 128 microg of budesonide in the pollen-season model used in this study. 相似文献
82.
Hirofumi CHIBA Surapon PIBOONPOCANUN Hiroaki MITSUZAWA Koji KURONUMA Robert C. MURPHY Dennis R. VOELKER 《Respirology (Carlton, Vic.)》2006,11(Z1):S2-S6
Objectives: The pulmonary surfactant system of the human lung consists of unique lipids and proteins that contribute to the biophysical and innate immune properties of the organ. Surfactant protein A (SP‐A) is an oligomeric protein consisting of 18 protomers with collagen and lectin–like domains that recognizes glycoconjugates, lipids and protein determinants on both host cells and invading microorganisms. The authors examined the interaction of SP‐A with Mycoplasma pneumoniae and the influence of the protein upon the innate immune response to the bacteria. Methodology: The authors quantified SP‐A interaction with bacteria using ELISA, and identified the major surface ligand by thin layer chromatography, HPLC and mass spectrometry. The inflammatory response of human and rat macrophages was measured by quantifying tumour necrosis factor‐α secretion using ELISA, and nitric oxide production. Results: SP‐A bound the bacteria with high affinity and enhanced the inflammatory response of human and rat macrophages to the organism and its membranes. Analysis of the interaction of SP‐A with the bacteria revealed that the major ligand was a phospholipid. The lipid ligand was purified by a combination of thin layer and HPLC, and identified by mass spectrometry. The mass spectrometry demonstrated that the SP‐A reactive lipid consisted of several disaturated molecular species of phosphatidylglycerol (PtdGro). Additional experiments were performed to determine if disaturated PtdGro was capable of interfering with the action of SP‐A as an inhibitor of bacterial lipopolysaccharide‐induced inflammatory mediator production by macrophages. The disaturated PtdGro failed to alter the anti‐inflammatory action of SP‐A but unexpectedly these same studies revealed that unsaturated PtdGro can modify the host response to lipopolysaccharide. Conclusions: These findings reveal that both the lipids and proteins of pulmonary surfactant play a role in regulating the host response to invading microorganisms. 相似文献
83.
失控的炎性反应和补体活化参与多脏器功能衰竭的发病过程。而因肠粘膜屏障功能衰竭造成的大量肠道细菌和内毒素侵入体内协同作用形成的肠源性感染在多脏器功能衰竭发病中所起的作用又日益受到关注。本研究给动物注射一种补体活化和炎性反应的活化因子——酵母多糖,观察炎症和感染两者间的内在关联性。结果发现,亚致死量的酵母多糖(0.1mg/g)可损伤肠粘膜屏障而导致肠道细菌侵入体内。而蛋白质营养不良却显著强化了酵母多糖的上述病理效应,使动物形成致死性的全身性肠源性感染,感染的严重性和动物的病死率随营养不良的程度进行性增高。结果表明,在体内失控的炎性反应和肠源性感染有协同致病效应。 相似文献
84.
Q. T. Dinh † D. A. Groneberg† C. Witt‡ C. Peiser† L. B. Cifuentes† N. Frossard§ B. F. Klapp A. Fischer† 《Clinical and experimental allergy》2004,34(12):1934-1941
BACKGROUND: The traditional neurotransmitter catecholamine and the neuropeptide tyrosine in sympathetic airway nerves have been proposed to be involved in the pathogenesis of airway diseases. OBJECTIVE: The aim of the present study was to investigate the effect of allergic airway inflammation on the expression of catecholamine enzyme tyrosine hydroxylase (TH), neuropeptide tyrosine (NPY) and tachykinins in mouse sympathetic airway ganglia. METHODS: Using neuronal tracing in combination with immunohistochemistry, the present study was designed to characterize TH, NPY and tachykinin profiles of superior cervical (SCG) and stellate ganglia after allergen challenge. RESULTS: The vast majority of fast blue-labelled SCG neurons (allergen: 97.5+/-1.22% (mean+/-SEM) vs. controls: 94.5+/-1.48%, P=0.18) and stellate neurons (allergen: 95.3+/-1.01% vs. controls: 93.6+/-1.33%, P=0.34) were immunoreactive for TH. Of the TH immunoreactive and fast blue-labelled SCG neurons, 52.0+/-1.01% allergen vs. 51.2+/-3.58% controls (P=0.83) and stellate neurons, 57.3%+/-0.97 allergen vs. 56.4+/-1.65% controls (P=0.64) were positive for TH only but not NPY, whereas 45.3+/-1.05% allergen vs. 43.3+/-1.18% controls (P=0.47) of fast blue-labelled SCG neurons and 37.9+/-0.86% allergen vs. 37.1+/-1.24% controls (P=0.62) of fast blue-labelled stellate neurons were immunoreactive for both TH and NPY immunoreactivities. There was a trend of an increase, but not significant one, in the percentage of TH-/NPY-immunoreactive and fast blue-labelled neurons in allergen-treated animals in comparison with the controls. Tachykinins, however, were not expressed by sympathetic neurons and were also not induced in sympathetic neurons after allergen challenge. CONCLUSION: The present study indicates that allergic airway inflammation does not alter the expression of noradrenalin and NPY in sympathetic ganglia and also shows that sympathetic neurons do not respond to allergic airway inflammation with tachykinins induction. However, a participation of catecholamine and NPY in the pathogenesis of allergic airway inflammation cannot be excluded in the present study as a higher neurotransmitter output per neuron following allergen challenge could be possible. 相似文献
85.
C. Sohy F. Pons A. Casset M.-P. Chesnard F. Lieutier-Colas P. Meyer G. Pauli F. de Blay 《Clinical and experimental allergy》2006,36(6):795-802
BACKGROUND: Endotoxin was proposed to increase the severity of asthma. Endotoxin levels greatly differ according to settings. In domestic environments, airborne concentrations may be dramatically low compared with levels reported in occupational settings. OBJECTIVE: Our first objective was therefore to assess the effect of inhalation of low-level lipopolysaccharide (LPS) on the immediate and late-phase asthmatic bronchial response. Our second objective was to evaluate the effect of exposure to LPS on the local and systemic inflammatory response. METHODS: Nineteen asthmatics sensitized to cat underwent on two separate occasions a bronchial challenge test to cat allergen (cat BCT) preceded randomly by a pre-exposure to either saline or LPS (2 microg). Methacholine challenge test was performed 24 h before exposure to LPS or saline. The Borg scale for dyspnoea and lung function were recorded before and after exposure to LPS or saline, and before and after cat BCT. Induced sputum and blood samples were collected before and after cat BCT, and analysed for cell counts and eosinophil cationic protein (ECP) levels. RESULTS: Inhalation of 2 microg LPS did not induce any changes in forced expiratory volume in 1 s (FEV1), peak expiratory flow (PEF), FEF 25-75 and Borg scale of dyspnoea. It neither modified Fel d 1 PD20 (45.03 ng as compared with 87.03; P=0.42). As well, there was no significant difference in late-phase reaction. Pre-exposure to LPS did not influence eosinophil counts or ECP levels in blood and sputum. CONCLUSION: Our study demonstrated that pre-exposure to LPS at low levels, which may be encountered in domestic environment, had no significant effect on the immediate and late-phase bronchial response to cat allergen. It neither modified local and systemic eosinophilic inflammation. 相似文献
86.
目的 :探讨急性重症胆管炎 (ACST)的病理生理学变化。方法 :制造急性重症胆管炎模型。实验大鼠随机分为正常组和ACST组。分别采用偶氮显色法和产色基质法测定外周血总胆红素和内毒素浓度。应用MTT法检测TNF、IL - 1、IL - 2和IL - 6活性。使用电子自旋共振仪和酸滴定法测定血氧自由基及血清磷脂酶A2 含量。通过放免分析方法检测PGFα/TXB2 比值。采用间接免疫荧光法观察T -淋巴细胞亚群。应用多功能生化测定仪检测补体和免疫球蛋白。结果 :急性重症胆管炎大鼠外周血总胆红素和内毒素浓度较正常组明显升高(p<0 0 0 1,p <0 0 5 ) ;TNF、IL - 1、IL - 2和IL - 6水平明显高于正常组 (p <0 0 5 ,p <0 0 1) ;血氧自由基、血清磷脂酶A2 含量明显升高 (p<0 0 1,p <0 0 5 ) ,PGFα/TXB2 ,比值明显降低 (p <0 0 5 )。急性重症胆管炎大鼠CD3 百分率明显高于正常组 (p <0 0 1) ,CD4/CD8比值明显低于正常组 (p <0 0 1) ;补体C3 和C4,免疫球蛋白LgM和IgA均明显高于正常组 (p <0 0 5 ,p<0 0 1)。结论 :急性重症胆管炎大鼠处在过度炎症反应、免疫功能紊乱状态 ,因此阻断细胞因子等炎症介质所致的继发性细胞损伤是其至关重要的治疗环节。 相似文献
87.
Alex W Wilson Stephen J Medhurst Claire I Dixon Nick C Bontoft Lisa A Winyard Kim T Brackenborough Jorge De Alba Christopher J Clarke Martin J Gunthorpe Gareth A Hicks Chas Bountra Daniel S McQueen Iain P Chessell 《European Journal of Pain》2006,10(6):537-549
Clinically, inflammatory pain is far more persistent than that typically modelled pre-clinically, with the majority of animal models focussing on short-term effects of the inflammatory pain response. The large attrition rate of compounds in the clinic which show pre-clinical efficacy suggests the need for novel models of, or approaches to, chronic inflammatory pain if novel mechanisms are to make it to the market. A model in which a more chronic inflammatory hypersensitivity phenotype is profiled may allow for a more clinically predictive tool. The aims of these studies were to characterise and validate a chronic model of inflammatory pain. We have shown that injection of a large volume of adjuvant to the intra-articular space of the rat knee results in a prolonged inflammatory pain response, compared to the response in an acute adjuvant model. Additionally, this model also results in a hypersensitive state in the presence and absence of inflammation. A range of clinically effective analgesics demonstrate activity in this chronic model, including morphine (3mg/kg, t.i.d.), dexamethasone (1mg/kg, b.i.d.), ibuprofen (30mg/kg, t.i.d.), etoricoxib (5mg/kg, b.i.d.) and rofecoxib (0.3-10mg/kg, b.i.d.). A further aim was to exemplify the utility of this chronic model over the more acute intra-plantar adjuvant model using two novel therapeutic approaches; NR2B selective NMDA receptor antagonism and iNOS inhibition. Our data shows that different effects were observed with these therapies when comparing the acute model with the model of chronic inflammatory joint pain. These data suggest that the chronic model may be more relevant to identifying mechanisms for the treatment of chronic inflammatory pain states in the clinic. 相似文献
88.
89.
火把花根片对哮喘豚鼠气道炎症抑制作用的实验研究 总被引:3,自引:0,他引:3
目的 研究火把花根片对哮喘豚鼠气道炎症的作用。方法 建立哮喘豚鼠动物模型。豚鼠17只随机分为2组,即对照组(8只)和火把花根组(9只)。测定支气管肺泡灌洗液(BAIF)细胞总数、嗜酸性粒细胞、淋巴细胞、中性粒细胞数量及蛋白浓度,图像分析软件测定气道壁厚度及腺体厚度。结果 火把花根组BAIF细胞总数、嗜酸性较细胞为主的炎性细胞数量及蛋白浓度均低于对照组(P<0.01),图像分析表明火把花根组气道壁厚度及腺体厚度均较对照组减低(P<0.01)。结论 火把花根片可抑制哮喘豚鼠的气道慢性炎症,对支气管哮喘有治疗作用。 相似文献
90.
Serial in vivo MR tracking of magnetically labeled neural spheres transplanted in chronic EAE mice. 总被引:5,自引:0,他引:5
Tamir Ben-Hur Ruud B van Heeswijk Ofira Einstein Michal Aharonowiz Rong Xue Emma E Frost Susumu Mori Benjamin E Reubinoff Jeff W M Bulte 《Magnetic resonance in medicine》2007,57(1):164-171
Neural stem cell (NSC) transplantation has been shown to attenuate the severity of experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). Central to the future success of NSC transplantation in MS is the ability of transplanted cells to migrate from the site of transplantation to relevant foci of disease. Using magnetically labeled mouse neurospheres and human embryonic stem cell (hESC)-derived neurospheres, we applied serial magnetic resonance imaging (MRI) to assess the biodynamics of transplanted cell migration in a chronic mouse EAE model. Magnetic labeling did not affect the in vitro and in vivo characteristics of cells as multipotential precursors. Cell migration occurred along white matter (WM) tracts (especially the corpus callosum (CC), fimbria, and internal capsule), predominantly early in the acute phase of disease, and in an asymmetric manner. The distance of cell migration correlated well with clinical severity of disease and the number of microglia in the WM tracts, supporting the notion that inflammatory signals promote transplanted cell migration. This study shows for the first time that hESC-derived neural precursors also respond to tissue signals in an MS model, similarly to rodent cells. The results are directly relevant for designing and optimizing cell therapies for MS, and achieving a better understanding of in vivo cell dynamics and cell-tissue interactions. 相似文献