Library

Notes: 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.

Notes: 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.

Notes: 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.

Notes: 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.

Notes: 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.

Notes: Abstract The white-rot fungus Trametes trogii excretes a main laccase showing a molecular mass of 70 kDa, acidic isoelectric point and N-terminal sequence homol-ogous to that of several phenol oxidases. The purified enzyme oxidizes a number of phenolic and non-phenolic compounds; recalcitrant molecules may be converted into substrates by introducing, in the correct position, o-␣or p-orienting ring-activating groups.