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21.
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
22.
Sabatini F Silvestri M Sale R Serpero L Raynal ME Di Blasi P Rossi GA 《Immunology letters》2003,89(2-3):215-224
When exposed to proinflammatory mediators, human bronchial epithelial cells (HBECs) upregulate the 'constitutive' adhesion molecule expression and cytokine/chemokine release. We tested whether and to what extent the inhibitory effect of fluticasone propionate on HBECs could involve the 'constitutive' and 'cytokine-induced' proinflammatory functions. Stimulation of the HBECs with interleukin (IL)-4 plus tumour necrosis factor (TNF)-alpha was more effective in upregulating intercellular adhesion molecule (ICAM)-1 ( approximately 2.2-fold increase) than vascular adhesion molecule (VCAM)-1 ( approximately 1.6-fold increase) expression (P<0.05) and in increasing the release of 'regulated on activation normal T cell expressed' (RANTES, 5.7-fold increase) than of IL-8 (3.5-fold increase) and granulocyte macrophage-colony stimulating factor (GM-CSF, 2.8-fold increase), (P<0.01). Fluticasone propionate, at the two concentrations tested (10 and 100 nM), was more effective in inhibiting the 'IL-4 plus TNF-alpha-induced' ICAM-1 expression than VCAM-1 expression (P<0.05) and in downregulating RANTES than IL-8 or GM-CSF secretion (P<0.05). The degree of inhibition demonstrated by fluticasone propionate appeared to be related to the degree of cell activation. In addition, for both adhesion molecules, the effect of fluticasone propionate at both concentrations tested appeared to be related to a complete inhibition of 'IL-4 plus TNF-alpha-induced' expression with no involvement of the 'constitutive' expression. Slightly different results were observed for cytokine/chemokine release. Indeed, evaluating RANTES, a complete inhibition of the 'IL-4 plus TNF-alpha-induced' release with a partial inhibition also of the 'constitutive' release at both concentrations of the drug tested was found, whereas for GM-CSF and IL-8, only a partial inhibition of the 'IL-4 plus TNF-alpha-induced' release in the presence of fluticasone propionate 10 and 100 nM. Thus, HBECs can constitutively or upon activation express adhesion molecules and secrete proinflammatory proteins at various levels and the different ability of fluticasone propionate to modulate the HBEC functions appears to be mostly related to the different inhibition of the various 'IL-4 plus TNF-alpha-induced' responses. 相似文献
23.
Silvestri JM Chen ML Weese-Mayer DE McQuitty JM Carveth HJ Nielson DW Borowitz D Cerny F 《American journal of medical genetics》2002,114(1):46-50
In the present study, we sought to identify genetic variation in the metabotropic glutamate receptor 3 (GRM3) gene, which has been mapped to chromosome 7q21.1-q21.2 [Scherer et al., 1996] and might contribute to genetic predisposition to schizophrenia and/or bipolar affective disorder. Using single-strand conformation analysis (SSCA), we screened the complete coding sequence as well as adjacent splice sites of the GRM3 gene in a sample of 46 bipolar affective and 46 schizophrenic patients. We detected three sequence variants: a rare C/T substitution at nucleotide position +885 (T209T), a C/T substitution at nucleotide position +2130 (Y624Y), and a more common C/T substitution at nucleotide position +1131 (A291A). The occurrence of the +1131C/T variant was investigated in a sample of bipolar affective patients (n=283), schizophrenic patients (n=265), and ethnically matched controls (n=227). We observed a significant overrepresentation of the +1131T allele in schizophrenic patients when compared to controls (P=0.0022). This finding was followed up in an independent sample of schizophrenic patients (n=288) and controls (n=162) and 128 schizophrenic trios but could not be confirmed. It is therefore unlikely that this variant plays a major role in predisposing to schizophrenia and/or bipolar affective disorder at least in the German population. 相似文献
24.
Mitochondrial import and enzymatic activity of PINK1 mutants associated to recessive parkinsonism 总被引:17,自引:0,他引:17
Silvestri L Caputo V Bellacchio E Atorino L Dallapiccola B Valente EM Casari G 《Human molecular genetics》2005,14(22):3477-3492
Parkinson's disease (PD) is a progressive neurodegenerative illness associated with a selective loss of dopaminergic neurons in the nigrostriatal pathway of the brain. Despite the overall rarity of the familial forms of PD, the identification of single genes linked to the disease has yielded crucial insights into possible mechanisms of neurodegeneration. Recently, a putative mitochondrial kinase, PINK1, has been found mutated in an inherited form of parkinsonism. Here, we describe that PINK1 mutations confer different autophosphorylation activity, which is regulated by the C-terminal portion of the protein. We also demonstrate the mitochondrial localization of both wild-type and mutant PINK1 proteins unequivocally and prove that a short N-terminal part of PINK1 is sufficient for its mitochondrial targeting. 相似文献
25.
Marazita ML Maher BS Cooper ME Silvestri JM Huffman AD Smok-Pearsall SM Kowal MH Weese-Mayer DE 《American journal of medical genetics》2001,100(3):229-236
Idiopathic congenital central hypoventilation syndrome (CCHS) is a very rare syndrome with major respiratory complications. Hypothesizing that CCHS is the most severe manifestation of general autonomic nervous system dysfunction (ANSD), we applied a case-control family study design to investigate the genetics of ANSD. Fifty-two probands with CCHS were identified, as well as 52 age-, race-, and gender-matched controls. ANSD phenotypic features were characterized in the cases, controls, and their family members. Our earlier studies found that most ANSD symptoms were more likely in CCHS cases and their relatives than in controls and their relatives (P < 0.05). The goal of the current study was to determine if the familiality of ANSD was consistent with a genetic pattern. We performed major locus segregation analysis of ANSD utilizing regressive models. CCHS probands were assumed to be affected; controls and relatives were designated as affected if they had two or more relevant symptoms. The hypothesis of "no transmission and no familial effects" was rejected in both case and control families. Case families were consistent with transmission of a major effect; control families were not (the difference in the pattern of results was significant, P < 0.0001). In the total data set, the best-fitting model was codominant Mendelian inheritance of a major gene for ANSD. These case-control family studies support our hypothesis that CCHS is the most severe manifestation of a general ANSD, with a family pattern consistent with Mendelian transmission, and demonstrate the potential utility of the approach to studies of other, similarly intractable disorders. 相似文献
26.
The balance between interleukin-1 (IL-1) and its competitive antagonist IL-1 receptor antagonist (IL-1Ra) may contribute to the pathogenesis of rheumatoid arthritis (RA). We analysed the frequency of different alleles in the IL-1B gene (at -511 and at +3954) as well as in the IL-1Ra gene (at +2018) in an association study involving 297 RA patients and 112 healthy controls from the same geographic area. We tested associations with RA susceptibility or severity, and with circulating levels of IL-1Ra and IL-1beta. Carriage of the rare IL-1B (+3954) allele 2 was increased in destructive arthritis (DRA) as compared to non-destructive arthritis (NDRA) (OR 1.7, 95% CI 1.1-2.8, 49.0% vs 35.9%) and controls (OR 1.7, 95% CI 1.1-2.8, 35.8%). Patients carrying this allele had a more destructive (Larsen wrist radiological index: mean +/- s.e.m., 2.1 +/- 0.2 vs 1.6 +/- 0.1, P = 0.005; Steinbrocker functional index: 2.4 +/- 0.1 vs 1.9 +/- 0.1, P = 0.002) and active disease (Ritchie articular index: 8.1 +/- 0.8 vs 5.3 +/- 0.6, P = 0.002; erythrocyte sedimentation rate (ESR): 36.6 +/- 2.9 mm/h vs 25.3 +/- 1.8 mm/h, P = 0.002). This contribution was independent from that of HLA DR4/DR1 to severity. IL-1Ra plasma levels adjusted to ESR values were significantly lower in IL-1B2 (+3954) positive than negative RA patients (1.0 +/- 0.1 vs 1.2 +/- 0.1 ng/ml, P = 0.01). This IL-1B (+3954) gene polymorphism may be an important marker for the severity of joint destruction in RA and is associated with an imbalance in IL-1Ra production. As this genetic association was independent and additive to the risk of HLA DR4/DR1 status, it could be a useful addition to HLA-DR4/1 as a genetic prognostic marker early in the course of the disease. 相似文献
27.
Complex and simple coronary artery stenoses: a new way to interpret coronary angiograms based on morphologic features of lesions 总被引:1,自引:0,他引:1
For many years, atherosclerotic coronary artery lesions have been described by angiographers only in terms of location and degree of narrowing. However, it has become apparent that coronary stenoses generally have distinct morphologic features that can be recognized at angiography and that allow them to be classified as either "simple" or "complex" plaques. Complex plaques are those characterized by ulcerated or ruptured surfaces, subintimal hemorrhage, superimposed partially occluding thrombi, recanalized thrombi, or some combination. Pathologic studies have shown a very high frequency of these lesions at sites of total thrombotic occlusion of coronary arteries. Clinical and angiographic studies have demonstrated a high frequency of such lesions in living patients with both unstable angina and acute myocardial infarction. The presence of complex stenoses has also been found to increase the risk of future myocardial infarction. Plaque morphology thus appears to significantly affect the prognosis of patients with coronary disease and should be carefully evaluated in interpretation of all coronary angiograms. 相似文献
28.
双—对二甲氨基苯甲醛缩二胺类希夫碱合成、表征及抗菌活性 总被引:9,自引:1,他引:8
目的:合成双-对二甲氨基苯甲醛缩二胺类希夫碱,并对其抗菌活性进行研究。方法:以对二甲氨基苯甲醛和二胺类为原料,经缩合反应,制得4种相应希夫碱。结果:结构经元素分析、红外光谱、核磁共振谱确定,4种化合物均未见文献报道,抗菌活性测试表明,它们具有一定抗菌活性。结论:乙酸是催化剂,对缩合反应有利,希夫碱化合物具有一定抗菌活性。 相似文献
29.
Giovina De Rosa Arnerico Testa Maurizio Maurizi Maria Antonietta Satta Claudia Aimoni Alberto Artuso Evelina Silvestri Vittoria Rufini Luigi Troncone 《European journal of nuclear medicine and molecular imaging》1990,17(3-4):179-184
A young woman with a thyroid papillary carcinoma behaving as an autonomously hyperfunctioning nodule is described. Only 17 similar patients have been seen in the past 25 years. It is emphasized that hyperthyroidism does not exclude malignant disease in hot nodules. This possibility suggests that all thyroid nodules, either cold or hot, require careful management. Therefore, in at risk cases, surgery could be the most useful treatment. 相似文献
30.
RAL Dampney Y. Hirooka PD Potts GA Head 《Clinical and experimental pharmacology & physiology》1996,23(Z3):105-111
- 1 It was first shown several years ago that the rostral part of the ventrolateral medulla (VLM) contains a high density of receptor binding sites for angiotensin II (AngII). In the present paper we briefly review recent studies aimed at determining the actions of both exogenous and endogenous angiotensin peptides in the rostral VLM, as well as their specific sites of action.
- 2 The results of these studies have shown that angiotensin peptides can excite pressor and sympathoexcitatory neurons in the rostral VLM, but do not appear to affect non-cardiovascular neurons in this region.
- 3 It is known that pressor neurons in the rostral VLM include both catecholamine and non-catecholamine neurons. There is evidence that, at least in conscious rabbits, both of these types of neurons are activated by AngII. The specific endogenous angiotensin peptide or peptides that affect pressor neurons in the rostral VLM have not yet been definitively identified.
- 4 It is also possible that different angiotensin peptides may have different effects on pressor neurons in the rostral VLM, mediated by different receptors. Further studies will be needed to define these different functions as well as the specific receptors and cellular mechanisms that subserve them.