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61.
62.
O Sacco S Lantero L Scarso L J Galietta D Spallarossa M Silvestri G A Rossi 《Annals of allergy, asthma & immunology》1999,83(1):49-54
OBJECTIVE: To test in vitro and in vivo the hypothesis that sodium nedocromil could modulate the expression of surface molecules on airway epithelial cells. METHODS: Human bronchial epithelial cells, obtained from surgically resected bronchi, were cultured and stimulated with recombinant IFN-gamma in the presence of sodium nedocromil. The intensity of the expression of surface molecules HLA-DR and ICAM-1 molecules on bronchial epithelial cells in vitro, was quantified by specific antibody staining and flow-cytometry analysis. Furthermore, we studied the effect of the drug on airway inflammation in vivo and on allergic rhinitis patients sensitized to house dust mites. Nasal epithelial cells were collected by brushing, at baseline and 2 to 3 weeks after treatment with sodium nedocromil. The expression of HLA-DR and ICAM-1 molecules was measured by flow-cytometry, and the proportions of neutrophils and eosinophils "contaminating" the epithelial cells evaluated by light microscopy examination of nasal brushings. RESULTS: The enhanced HLA-DR and ICAM-1 expression, induced by IFN-gamma, was effectively downregulated, in a dose-dependent manner, by sodium nedocromil. At all the concentrations tested (10(-9) to 10(-4) M), the inhibitory activity of the drug was stronger on HLA-DR than on ICAM-1 expression (P<.05, all comparisons). As compared with healthy subjects, patients with allergic rhinitis had a higher expression of HLA-DR (P<.05) but not of ICAM-1 molecules (P>.05) on nasal epithelial cells, and higher proportions of nasal eosinophils (P<.05). Treatment with sodium nedocromil downregulated the expression of HLA-DR (P<.05), but not of ICAM-1 (P>.05), and induced a mild, but not statistically significant, decrease of nasal eosinophilia (P>.05). CONCLUSION: These data demonstrate that the antiinflammatory activity of sodium nedocromil may include modulation of surface molecule expression on airway epithelial cells. 相似文献
63.
Ricciardolo FL Caramori G Ito K Capelli A Brun P Abatangelo G Papi A Chung KF Adcock I Barnes PJ Donner CF Rossi A Di Stefano A 《The Journal of allergy and clinical immunology》2005,116(5):1028-1035
BACKGROUND: Reactive nitrogen species, formed via the reaction of nitric oxide (NO) with superoxide anion and via (myelo)peroxidase-dependent oxidation of NO(2)(-), have potent proinflammatory and oxidizing actions. Reactive nitrogen species formation and nitrosative stress are potentially involved in chronic obstructive pulmonary disease (COPD) pathogenesis. OBJECTIVES: To investigate the expression of markers of nitrosative stress, including nitrotyrosine (NT), inducible NO synthase (iNOS), endothelial NO synthase (eNOS), myeloperoxidase (MPO), and xanthine oxidase (XO) in bronchial biopsies and bronchoalveolar lavage from patients with mild to severe stable COPD compared with control groups (smokers with normal lung function and nonsmokers). METHODS: The expression of NT, iNOS, eNOS, MPO and XO in the bronchial mucosa and bronchoalveolar lavage of patients was measured by using immunohistochemistry, Western blotting, and ELISA and correlated with the inflammatory cell profile. RESULTS: Patients with severe COPD in stable phase had higher numbers of NT(+) and MPO(+) cells in their bronchial submucosa compared with mild/moderate COPD, smokers with normal lung function, and nonsmokers (P < .01). iNOS(+) and eNOS(+) but not XO(+) cells were significantly increased in smokers with COPD or normal lung function compared with nonsmokers (P < .05 and P < .01, respectively). In patients with COPD, the number of MPO(+) cells was significantly correlated with the number of neutrophils (r = +0.61; P < .0025) in the bronchial submucosa. Furthermore, the number of NT(+) and MPO(+) cells was negatively correlated with postbronchodilator FEV(1). CONCLUSION: These data suggest that nitrosative stress, mainly mediated by MPO and neutrophilic inflammation, may contribute to the pathogenesis of severe COPD. 相似文献
64.
Clinical,immunological, and molecular analysis in a large cohort of patients with X-linked agammaglobulinemia: an Italian multicenter study 总被引:5,自引:0,他引:5
Plebani A Soresina A Rondelli R Amato GM Azzari C Cardinale F Cazzola G Consolini R De Mattia D Dell'Erba G Duse M Fiorini M Martino S Martire B Masi M Monafo V Moschese V Notarangelo LD Orlandi P Panei P Pession A Pietrogrande MC Pignata C Quinti I Ragno V Rossi P Sciotto A Stabile A;Italian Pediatric Group for XLA-AIEOP 《Clinical immunology (Orlando, Fla.)》2002,104(3):221-230
A questionnaire-based retrospective clinical and immunological survey was conducted in 73 males with a definite diagnosis of X-linked agammaglobulinemia based on BTK sequence analysis. Forty-four were sporadic and 29 familial cases. At December 2000, the patients' ages ranged from 2 to 33 years; mean age at diagnosis and mean duration of follow-up were 3.5 and 10 years respectively. After the mid-1980s all but 2 were on intravenous immunoglobulin (IVIG) substitution therapy, with residual IgG >500 mg/dl in 94% of the patients at the time of enrollment. Respiratory infections were the most frequent manifestation both prior to diagnosis and over follow-up. Chronic lung disease (CLD) was present in 24 patients, in 15 already at diagnosis and in 9 more by 2000. The cumulative risk to present at diagnosis with CLD increased from 0.17 to 0.40 and 0.78 when the diagnosis was made at the ages of 5, 10, and 15 years respectively. For the 9 patients who developed CLD during follow-up, the duration of follow-up, rather than age at diagnosis; previous administration of intramuscular immunoglobulin; and residual IgG levels had a significant effect on the development of CLD. Chronic sinusitis was present in 35 patients (48%), in 15 already at diagnosis and in 20 by 2000. Sistemic infections such as sepsis and meningitis/meningoencephalitis decreased over follow-up, probably due to optimal protection provided by high circulating IgG levels reached with IVIG. 相似文献
65.
Scarano MI De Rosa M Panariello L Carlomagno N Riegler G Rossi GB Bucci L Pesce G Toni F Renda A Izzo P 《Human mutation》1999,13(3):256-257
Germline mutations within the adenomatous polyposis coli (APC) gene, a tumor suppressor gene, are responsible for most cases of familial adenomatous polyposis (FAP), an autosomal dominantly inherited predisposition to colorectal cancer. To date, more than 300 germ-line causative mutations within this gene have been described (Beroud and Soussi, 1996). Of these, about 95% are chain-terminating mutations, and more than 60% have been localized within exon 15 (Nagase and Nakamura, 1993, Beroud and Soussi, 1996). Using polymerase chain reaction-single strand conformation polymorphism, protein truncation test (PTT) and DNA sequencing we have identified five new frameshift mutations (2523insCTTA, 2638delA, 2803insA, 3185delAA, 4145delTCATGT), all occurring within exon 15 and giving rise to truncated protein products. Two of these new mutations are of particular interest because of the unusual phenotypic features shown by probands. The phenotype of the proband bearing the 2523insCTTA mutation at codon 842 was very aggressive with onset of the symptoms at 12 years, while the patient bearing the 3185delAA mutation at codon 1062 exhibited features of an attenuated form of FAP (AAPC). Our data reiterate the great heterogeneity of the mutational spectrum in FAP that gives rise to an extreme variability of the clinical expression. 相似文献
66.
67.
In this investigation, the ultrastructural features of the nutritional cardiomyopathy of protein-calorie-malnourished rats were examined. Protein-calorie malnutrition was induced in young rats by feeding them a low-protein diet (4% protein) for 6 weeks. Control animals were fed a high-protein diet (16% protein). The deficient rats showed severe restriction of body-weight gain, fatty liver and hypoproteinaemia. The results of the present study clearly demonstrated that the experimentally induced protein-calorie malnutrition brings about striking morphological changes in the heart of the rat. On light microscopy hyalinization an vacuolization of muscle fibres, loss of cross striations and myofibrils, small foci of necrosis, interstitial fibrosis and mononuclear-cell infiltration could be detected. The ultrastructural lesions were characterized by myofibrillar degeneration, contraction-band formation, dilatation of sarcoplasmic reticulum, mitochondrial swelling, dehiscence of intercalated discs, and widened interstitial spaces, especially around vessels, due to oedema fluid and cellular infiltration by mononuclear cells an activated fibroblasts with collagen fibres and microfibrils. In addition, an increase in relative heart weight was also observed. The potential role of catecholamines in the pathogenesis of this cardiomyopathy is discussed. 相似文献
68.
Cascade filtration: clinical application in 26 patients with immune complex and IgM mediated diseases 总被引:1,自引:0,他引:1
M Valbonesi L Mosconi F Montani G Florio U Rossi 《The International journal of artificial organs》1983,6(6):303-307
A new technique which allows lymphocytapheresis to be combined with cascade filtration (CF) is described in this paper. This therapeutical approach was applied for the treatment of patients affected by necrotizing vasculitis (1), inflammatory myopathies (5), Cryoglobulinemia (5), immune complex polyneuropathies (7), rheumatoid arthritis (3) and psoriasis (3 patients). Two cases of Waldenstrom's macroglobulinemia were also treated after the onset of the hyperviscosity syndrome. 78 procedures have been performed without any untoward effect. From a clinical point of view all patients had some improvement following treatment, thereby confirming not only the clinical safety of this therapeutical approach but also its effectiveness at least in the management of diseases which usually respond to plasma exchange treatment. Laboratory investigations showed that with CF it is possible to selectively remove IgM, immune complexes, fibrinogen, lipoproteins and high molecular weight plasma components, sparing most albumin and IgG globulins (85 and 71%, respectively). 相似文献
69.
This report describes a 69 year old woman, suffering from active rheumatoid arthritis since the age of 60 and presenting with severe dyspnoea and cough. A computed tomography scan of the chest showed multiple bilateral pulmonary nodules, sometimes cavitated, associated with reticular opacities and pleural effusion. A videothoracoscopic excision of a cavitated nodule was performed. Seven days after surgery, a right pneumothorax developed, and the patient died of septicaemia one month later. Microscopically, the excised nodule was composed of necrotic fibrinoid material with a peripheral rim of palisaded histiocytes, extending to the pleural surface and containing several fungal hyphae morphologically consistent with aspergillus. A diagnosis of pulmonary rheumatoid nodule with fungus colonisation was made. In the lung, fungus colonisation is a rare complication of rheumatoid nodules. The most important differential diagnostic considerations are briefly discussed. 相似文献
70.
Characterization of a bovine collagen-hydroxyapatite composite scaffold for bone tissue engineering 总被引:9,自引:0,他引:9
Rodrigues CV Serricella P Linhares AB Guerdes RM Borojevic R Rossi MA Duarte ME Farina M 《Biomaterials》2003,24(27):4987-4997
Different biomaterials have been used as scaffolds for bone tissue engineering. Here we characterize a biomaterial composed of sintered (1100 degrees C) and powdered hydroxyapatite (HA) and type I collagen (Coll), both of bovine origin, designed for osteoconductive and osteoinductive scaffolds. Coll/HA proportions were 1/2.6 and 1/1 (wet weight), and particles sizes varied from 200 to 400 microm. Vv (volume density) and Sv (surface to volume density) for the HA particles in the composite ranged from 0.48 +/- 0.06 to 0.55 +/- 0.02 and 5.090 +/- 0.545 to 6.366 +/- 0.289 microm(-1), respectively. Due to the relatively small changes in Vv and Sv, a macroporosity could be characterized for the biocomposite. X-ray diffraction and infrared spectroscopy showed that the sintered bone was composed essentially of HA with minimum additional groups such as surface calcium hydroxide, surface and crystal water, free carbon dioxide and possibly brushite. Mass spectrometry detected carbonates at A and B sites of HA, and weakly bound to the structure. Human osteoblasts adhered and spread on both the HA particle surface and the collagen fibers, which seemed to guide cells between adjacent particles. The biocomposite studied has several characteristics considered as ideal for its use as a scaffold for osteoconduction and osteoinduction. 相似文献