Bibliothek

Notizen: An aligned nematic droplet in the axial configuration is modeled as a hollow spheric scatterer for studying its small angle light scattering characters. When the thickness of the shell is reduced by an external field, calculations by anomalous diffraction approximation suggest that scattering intensity would decrease and scattering peak would drift to a smaller angle. Measured angular scattering intensities show good agreement with calculations. As the shell part originates from anchoring of the nematic molecules to the surrounding medium, angular scattering intensity can be associated with correlation length. © 1996 American Institute of Physics.

Notizen: Several reports have shown that HLA-B8,DR3 positive subjects may display some changes in immune parameters when compared with HLA-B8,DR3 negative ones and are prone to develop several immunological diseases. In the present study we have analysed the proliferative response to phytohaemagglutin (PHA) in HLA-typed healthy subjects. A twin method was also employed to assess the role of genetic and environmental factors in the regulation of the response to the mitogen. It was not possible to demonstrate any difference in proliferative response to optimal doses of PHA between groups of subjects carrying or not carrying the HLA-B8,DR3 phenotype. When suboptimal responses were studied, however, the results showed that ly-mphocyte responses were significantly decreased in HLA-B8,DR3 positive subjects compared with the negative ones. Moreover, the experiments performed with twins demonstrated that environmental factors were more important than genetic factors in the proliferative response to mitogen. The fact that the HLA-B8,DR3 phenotype affects the suboptimal response to PHA although environmental factors are more important than genetic factors in the response to the mitogen seems of some interest. However, these results could be consistent with the high incidence of autoimmune disorders among HLA-B8,DR3 positive individuals.

Notizen: Background Initial attempts to evaluate the association between allergic rhinitis and nonspecific bronchial responsiveness has produced conflicting results. In fact, some studies showed a strong correlation and other failed to find an association. However, little is known about the effect of natural specific allergen exposure on the bronchial reactivity of mono-sensitive patients with rhinitis in the southern Mediterranean area, in relation to skin reactivity to allergens, total serum IgE levels and blood eosinophiis.Objectives The significance of the association between allergic rhinitis, and abnormal airway responsiveness with regard to the pathogenesis of asthma is unclear. For this reason, we have studied non-specific bronchiai hyperreactivity. in patients with seasonal allergic rhinitis, with reference to the responsible allergen. The aim of the study was to correlate the responsiveness to bronchoprovocation with methacholine in subjects a with allergic rhinitis during and out of the pollen season with total serum IgE and blood eosinophils.Methods Fourty-nine non-smoking patients with clinical diagnosis of allergic rhinitis and mono-sensitive skinprick tests to pollen allergens were enrolled in the study. Twenty patients suffered from seasonal rhinitis to Parietaria pollen. 15 patients to Gramineae pollen and 14 patients to Olea pollen. In all patients lung function measurements (assessed as response to methacholine). tolal serum IgE and blood eosinophii counts were measured during and out of the pollen season.Results During pollen season. 16 out of 49 rhinitis patients demonstrated values of bronchial responsiveness measured as response to inhaled metbacholine in the asthmatic range whereas out of the pollen season only eight patients were in the asthmatic range. By analysing the results with reference to the responsible allergen, during the pollen season 5 out of 16 patients were Parietaria -sensitive and out of the pollen season seven out of eight patients. Finally, in Parietaria -sensitive rhinitis bronchial responsiveness signifi-cantly correlated, during and out of the pollen season, with total serum IgE and with blood eosinophil counts.Conclusions Our results are consistent with the hypothesis that Parietaria is more important than Olea and Gramineae as a risk for developing non- specific bronchial hyperresponsiveness. On the whole, present observations provide further evidence that there is an interrelationship of allergen kind, total serum IgE. eosinophil and bronchial hyperressponsiveness suggesting that they may play a role in the development of bronchial asthma in rhinitis patients.

Notizen: Background Corticosteroids are considered to be particularly effective in reducing nasal congestion and are therefore recommended as first-line treatment in allergic rhinitis patients with moderate to severe and/or persistent symptoms.Objective We compared the clinical efficacy of fluticasone propionate aqueous nasal spray (FPANS) 200 μg given once daily, administered in mono-therapy or combined therapy with a H1 receptor antagonist (cetirizine, CTZ) or with a leukotriene antagonist (montelukast, MSK), and the combined therapy of CTZ plus MSK in the treatment of patients affected by allergic rhinitis to Parietaria during natural pollen exposure. In addition, we examined the effect of the treatment on eosinophil counts and eosinophil cationic protein (ECP) in nasal lavage performed at beginning of season, during season and at the end of the season.Methods One hundred patients aged 12–50 years (mean±SD 31.8±9.6) with a history of moderate to severe Parietaria pollen-induced seasonal allergic rhinitis were selected. A randomized, double-blind, double dummy, placebo (PLA)-controlled, parallel-group study design was used. Patients were treated FPANS 200 μg once daily (n=20) or with FPANS 200 μg once daily, plus CTZ (10 mg) in the morning (n=20), or with FPANS 200 μg once daily, plus MSK (10 mg) in the evening (n=20) or with CTZ (10 mg) in the morning plus MSK in the evening (n=20) or matched PLA (n=20). Assessment of efficacy was based on scores of daily nasal symptoms and on eosinophil counts and ECP in nasal lavage.Results All treatments showed significant differences (P〈0.001) compared with PLA in terms of total symptom, rhinorrhea, sneezing and nasal itching scores. Concerning nasal congestion on waking and daily only the groups treated with FPANS in mono-therapy or in combined therapy showed significant differences compared with PLA. Comparing the group treated with FPANS alone and the groups treated with FPANS plus CTZ, we found significant differences for total symptom score (P=0.04) and for nasal itching (P=0.003). The comparison between FPANS plus CTZ and FPANS plus MSK showed significant difference for nasal itching (P=0.003). Finally, there were significant differences between the group treated with FPANS and the group treated with CTZ plus MSK for total symptom score (P=0.009), for nasal congestion on waking (P〈0.001) and nasal congestion daily (P〈0.001). Also the comparisons between the group treated with FPANS plus CTZ and the group treated with CTZ plus MSK demonstrated significant differences (P〈0.001) for total symptom, for nasal congestion on waking and for nasal congestion on daily, for rhinorrhea (P=0.04) and for nasal itching (P=0.003) scores. Concerning the comparison between the group treated with FPANS plus MSK and the group treated with CTZ plus MSK we found significant differences for total symptom score (P=0.005), for nasal congestion on waking (P〈0.001) and for nasal congestion on daily (P〈0.001). No other differences were observed between the groups. Concerning blood eosinophil counts, significant differences were found between the treatments with FPANS in mono-therapy or in combined therapy with PLA group during and at the end of the season (P=0.0003 and P〈0.0001, respectively). Concerning eosinophils and ECP in nasal lavage, all treatments showed significant differences (P〈0.001) compared with PLA. Besides, there were significant differences (P〈0.001) between the groups treated with FPANS alone or in combined therapy and the group treated with CTZ plus MSK.Conclusion The results of this comparative study demonstrate that FPANS is highly effective for treating patients affected by allergic rhinitis, with efficacy exceeding that of CTZ plus MSK in combined therapy. In addition, the regular combined therapy of FPANS plus CTZ or plus MSK would not seem to offer substantial advantage with respect to FPANS in mono-therapy in patients affected by seasonal allergic rhinitis.

Notizen: Abnormal increments of pro-inflammatory cytokines (IL-6 and TNF-α) characterize the outbreak of infectious diseases, which are the major cause of death in the elderly. A counterbalance to the inflammation is exerted by IL-10 with an inhibitory role on TNF-α production. As is well known, some cytokine gene polymorphisms influence the cytokine production, playing a role as susceptibility or resistance factors against immune-mediated and infectious disease. Genetic variations in the −308A/G locus for TNF-α seems to affect the clinical outcome of some infectious diseases. In fact, the −308A allele is associated with severe septic shock and death. On this basis, we have screened healthy old subjects, nonagenarians and old patients affected by the acute phase of chronic obstructive bronchitis and bronchopneumonia of bacteria origin for the −308G/A locus (PCR–RFLP). Subjects are grouped in A+ (AG, AA genotypes) and A– (GG genotype) and data on IL-6, TNF-α, IL-10, NK cell cytotoxicity, zinc and metallothioneins (MTs) gene expression (RT–PCR) were stratified according to different TNF-α genotypes. The frequency of the A allele was increased in infected patients in comparison with healthy old controls. No differences existed between A+ and A– young adult, old and nonagenarian controls in tested parameters. Conversely, A+-infected patients displayed elevated IL-6, TNF-α and MTmRNA, low IL-10 coupled with impaired NK cell cytotoxicity and lower zinc ion than A– patients. However, the data reported are gender independent. Therefore, the −308A polymorphism at the locus of TNF-α may be one of the susceptibility factor for infectious diseases in old persons, particularly considering its association to the increased release of pro-inflammatory cytokines and to the reduction of zinc release and MTs synthesis involved in the control of the inflammatory response. These data strongly suggest that the genetic screening of the −308G/A polymorphism may be a valid tool for identification of subjects needing a more appropriate therapy when affected by acute and/or recurrent infectious diseases.

Notizen: Several studies show that inflammatory components may contribute to atherosclerosis and increase the risk for myocardial infarction (MI). Interleukin-6 (IL-6) is a key pro-inflammatory and immune-modulatory cytokine of relevance for cardiovascular diseases. In this case-control study, 200 patients with MI and 257 healthy controls were genotyped for the polymorphism present in −174 promoter region of the IL-6 gene. Plasma concentrations of IL-6 and C-reactive protein (CRP) in a group of patients and controls were measured. The −174 C allele was associated with an increased risk of developing MI (OR = 2.886, c.i. = 1.801–4.624, P = 0.0001) in older patients, while no association was found in younger ones. The IL-6 plasma levels were higher in patients with MI carrying the CC genotype than in GG patients (CC carriers, IL-6 = 2.97 pg mL−1 vs. GG carriers = 1.81 pg mL−1, P = 0.016). A positive correlation of IL-6 levels with those of CRP in serum from patients with MI was also found. Data from this study suggest that the C allele of the promoter polymorphism in the IL-6 gene is a risk factor for MI in the elderly, and the production of the IL-6 is differentially affected by different genotypes of the IL-6 −174 promoter polymorphism.

Notizen: Background: The recovery of mediator metabolites from urine has the potential to provide a rapid, safe, and easily available index of release of mediators. We aimed to determine urinary metabolites of both histamine and leukotrienes (LTs) in patients affected by chronic urticaria (CU).Methods: Twenty patients with CU were studied. They were selected on the basis of double-blind placebo-controlled challenge (DBPC) with acetyl salicylic acid (ASA) and food additives. Ten patients (group B) were negative to both challenges. Ten patients (group C) presented urticaria and/or the appearance of angioedema during or 24 h after challenge, with reactions to ASA (five patients) or food additives (five patients). We recruited 15 healthy volunteers as controls (group A). During a second challenge, groups B and C were challenged double-blind with a single dose of ASA, or a specific food additive, or placebo. The healthy group was challenged only with a placebo (talc capsule). Patients in groups B and C were challenged twice: with placebo (as groups B1 and C1) and with ASA (groups B2 and C2) or food additives (C2). Four samples of urine were collected; one during the night before the specific or sham challenge (baseline), and three at 2, 6 and 24 h after the challenge. Urinary methylhistamine (N-MH) and LTE4 were analyzed and normalized for urinary creatinine.Results: For urinary N-MH at baseline, there was a significant difference only between group A and groups B1, B2, C1 and C2 (A vs. B1, P 〈 0.0001; A vs. B2, P 〈 0.0001; A vs. C1, P 〈 0.0001; A vs. C2, P 〈 0.0001). We detected a significant variation in urinary methylhistamine excretion only in group C2 after 2 h, 6 h and 24 h (P 〈 0.0001). However, no variations were observed in N-MH excretion rate in the other groups (A, B1, C1) after challenge with placebo, and in B2 after challenge with ASA 20 mg. For urinary LTE4 at baseline no differences were found between the mean values for the different groups. After specific challenge, only C2 patients showed significantly increased excretion rates of urinary LTE4 compared with the other groups challenged with placebo (A, B1, C1), or ASA (B2) (P 〈 0.0001). No significant correlation was seen between urinary LTE4 and methylhistamine excretion rate in any patients.Conclusion:  Our results show that urinary excretion of N-MH and LTE4 is different for CU patients without ASA or food hypersensitivity, compared to those with CU with ASA or food additive hypersensitivity after specific challenge.