Search PubMed⌕ Search

Biomedical subjects

R Palacios

Publications and source records attributed to R Palacios.

222 records · Page 13Linked to original sources
PubMedDate not supplied

Fungal allergens from important allergenic fungi imperfecti.

Occurrence of several fungal species in the environment seems to be related to hypersensitivity disorders in humans. Fungal allergen studies reported in the literature are reviewed regarding to Aspergillus, Alternaria, Penicillium and Cladosporium genera. In this paper, we study by means of in vivo (Skin Prick Test) and in vitro (RAST and immunoblotting) the classical question of the best source of allergenic material using a population of asthmatic patients sensitized to different mould genera. In Alternaria alternata, RAST values are considerably higher in metabolic extracts (culture filtrate) than in somatic ones (myceliar). In Alternaria alternata and Penicillium chrysogenum, low molecular weight allergens (< 30 kDa) show higher IgE-binding activity in culture filtrate extracts. In Aspergillus fumigatus we find some relevant allergens in the mycellium. Different fractions have also been used in skin tests and culture filtrate extracts showing higher potency than myceliar ones, what is in agreement with the former results. We found in Penicillium chrysogenum that the 67 kDa allergen, similar to what described by Shen et al (1991), showed inespecific binding to anti-IgE conjugate used in the development of the immunoblotting technique. Whether or not this component could be a major allergen is discussed. We discuss about the importance of the biology of fungi in the sensitization and development of mould allergy.

Allergens↗
PubMedDate not supplied

[A new method of administration of budesonide powder for the treatment of allergic rhinitis].

The efficacy and safety of a new device for administering powdered budesonide in allergic rhinitis was evaluated. This method eliminates the disadvantages of traditional preparations and improves dosing and administration, even at low nasal flow rates. A randomized, controlled, single-blind study was made in 66 patients with allergic rhinitis, half of whom were assigned to the experimental treatment (powdered budesonide) and half to a standard aerosol. Results showed that both preparations were very effective (p < 0.01) in controlling rhinitis symptoms and not significantly different. However, the overall patient evaluation was significantly better (p < 0.01) in the group treated with powdered budesonide. Both treatments elicited a similar tolerance, although tolerance of powdered budesonide was slightly better. To conclude, treatment with the new powdered budesonide dispenser was as effective and well-tolerated as standard treatment, and better accepted by patients.

Adult↗
PubMedDate not supplied

Comparative allergenic study of Tetranychus urticae from different sources.

Tetranychus urticae is a macroscopic mite known as "red spider mite". It is a cosmopolitan and polyphagous mite which parasitizes both fruit trees and herbaceous plants, particularly in greenhouses. Contribution of T. urticae to occupational asthma among greenhouse workers has been studied to identify and describe the main T. urticae allergens. In this study we described and compared the physiochemical characteristics of the main. T. urticae allergens from three different sources, carnation, cucumber and vegetable marrow. Forty-two green-house workers with occupational T. urticae allergy were included. Extracts were prepared from mite bodies collected from the three different sources; skin prick tests, specific IgE, SDS-PAGE and SDS-PAGE immunoblotting were carried out with the three T. urticae extracts. Cross-reactivity was measured by RAST inhibition. These assays were done with each of the three extracts in solid and fluid phases. All patients showed a positive prick test to T. urticae extracts from carnation, 39 (93%) to those from cucumber, and 34 (81%) to those from vegetable marrow. Specific IgE was positive in 80% of patient sera from T. urticae extract from carnation, 58% and 63% in that from cucumber and vegetable marrow, respectively. SDS-PAGE immunoblotting of the extracts showed coincident and relevant allergens. The similar curve obtained by RAST inhibition assays revealed the high epitope similarity from the three extracts. In conclusion, T. urticae extracts from parasitic carnation, cucumber and vegetable marrow cultures showed a high epitope similarity with three relevant allergens with molecular mass of 25, 19 and 15 to 17 kDa.

Adolescent↗
PubMedDate not supplied

Influence of mite growth culture phases on the biological standardization of allergenic extracts.

House dust mites are a well known cause of asthma and other respiratory allergies. In order to improve the standardization of allergenic extracts for diagnosis and immunotherapy, it is important to determine the frequency and concentration of the components, both the major and the minor allergens during the growth period of the mite population. In a previous paper we demonstrated that the laboratory cultures of Dermatophagoides pteronyssinus and Dermatophogoides farinae exhibited three well differentiated growth phases: latency, exponential growth, and death of the culture. Biological standardization of extracts from the two mite species were carried out by skin prick tests in a group of 20 patients, using different concentrations of the extracts at the three growth phases. The patient sera were also studied by means of the RAST technique to determine the levels of specific IgE for each phase. The extracts produced from the exponential growth phase of the cultures revealed six times more relative allergenic activity in in vivo studies, and average RAST values were approximately three times higher than those extracts from latency and death phases. The reproducibility of the extract production method was assessed by comparing different batches obtained in similar conditions. The results showed batch-to-batch homogeneity allergenic activity. In conclusion, it was demonstrated that extracts obtained from cultures with the highest concentration of live mites (maximum growth phase) render the best diagnostic results in vivo and in vitro.

Adolescent↗
PubMedDate not supplied

Extracts from various mite species contain cross-reactive and noncross-reactive IgE epitopes. A RAST inhibition study.

Previous studies have demonstrated the high incidence of Dermatophagoides, Euroglyphus, Blomia, Lepidoglyphus and Chortoglyphus spp. sensitizations in a mite-allergic population. The aim of this study was to evaluate immunological cross-reactivity among the above mentioned groups, using sera from a nonrural population allergic to mites, from a subtropical area (Canary Islands). RAST inhibition studies demonstrated significant cross-reactivity among Dermatophagoides and Euroglyphus species (> or = 65% of maximum theoretical inhibition), as also noted by other authors. Blomia kulagini demonstrated scarce cross-reactivity with Dermatophagoides, Lepidoglyphus and Chortoglyphus species (< or = 30% of maximum theoretical inhibition) and medium level with Euroglyphus maynei (45% of maximum theoretical inhibition). Chortoglyphus arquatus demonstrated high cross-reactivity levels with the other species studied. The results obtained in this study demonstrated the scarce immunological cross-reactivity between Pyroglyphidae and non-Pyroglyphidae mites, thus suggesting the polysensitization of the studied population to different mite species.

Adolescent↗