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R Codina

Publications and source records attributed to R Codina.

24 records · Page 2Linked to original sources
PubMed1993

Preventing asthma epidemics due to soybeans by dust-control measures.

BACKGROUND: The inhalation of soybean dust released during the unloading of soybeans into a silo caused outbreaks of asthma in Barcelona, Spain. This study was designed to determine morbidity due to asthma and serum IgE reactivity before and after the installation of filters in the silo. METHODS: We measured soybean-allergen concentrations in 136 samples of air collected for 9 months before and 24 months after the installation of filters. We compared the number of days on which there was an unexpected increase in emergency room visits for asthma, the number of days on which the number of emergency room visits for asthma in one four-hour period was so high that it was unlikely to be due to chance, and the mean daily number of emergency room and intensive care unit admissions for asthma for a total of 60 months before and after filter installation. Serum IgE antibodies against soybean allergens were measured in 38 patients before and after filter installation. RESULTS: The concentration of airborne soybean allergens on days when soybeans were unloaded decreased from 324 to 25 U per cubic meter after the installation of filters (P < 0.001). The number of days on which there was an unusually large number of visits to the hospital for asthma and the number of days on which asthma was epidemic both decreased significantly (both P < 0.001), from 29 to 6 and from 18 to 0, respectively. The mean daily number of emergency room and intensive care unit admissions for asthma on days when soybeans were unloaded decreased from 8.3 to 5.4 and from 0.26 to 0.01, respectively (both P < 0.001). The mean serum IgE antibody concentrations in the 38 patients studied decreased from 2 Pharmacia reference units per milliliter to 1 (P < 0.001). CONCLUSIONS: Installing filters on silos to prevent airborne dissemination of allergenic soybean dust eliminates outbreaks of asthma caused by inhalation of the dust, thus supporting the idea that the avoidance of allergens helps prevent asthma.

Adolescent↗
PubMed1992

[Normal values of the immunoglobulin G subclasses in an adult population. Importance in a study of their deficiency].

BACKGROUND: Quantification of the IgG subclasses (IgGS) requires highly sensitive and specific techniques since their molecular structure is more than 95% homologous. At present, ELISA and RIA are the most appropriate techniques; although the variability of these techniques and the possible ethnic differences in serum levels of IgGS oblige each laboratory to establish its own reference values in a normal population, a condition necessary for defining IgGS deficits. METHODS: In the present study the normal serum values of IgGS in 100 healthy individuals were established. Serum quantification of the IgGS was performed by optimization of the indirect ELISA technique using AcMo and OMS reference standards H00-03 for the 4 subclasses, calibrated vs the OMS WHO 67/97 pattern. RESULTS: Normal values observed for IgG1 were 2.61-10.81 g/l; IgG2, 1.12-4.08 g/l; IgG3, 0.22-2.88 g/l; and IgG4, 0.05-1.56 g/l obtained as of the mean +/- 2 SD for IgG1 and as of the extent of the values of the remaining 3 subclasses by following a non-normal distribution. The sensitivity of the technique was 0.05 g/l with mean intra and inter analysis coefficients of 3.5% and 10.7% respectively. The correlation between total IgG and the sum of the 4 subclasses showed a r = 0.894 (p less than 0.01). CONCLUSIONS: The ELISA technique using AcMo and OMS reference standards is an adequate method for the quantification of the IgG subclasses. However, given the variability of this technique and in order to avoid error, strict working conditions, such as the use of control sera at 2 concentration levels, should be observed for the 4 IgGS in each of the analytic series and each series should also be duplicated.

Adult↗
PubMed1992

Risk factors of soybean epidemic asthma. The role of smoking and atopy.

Epidemics of emergency room admissions for asthma occurring in Barcelona during the period 1981 to 1987 were caused by inhalation of soybean dust. To investigate the risk factors that determined why some asthma patients became reactive to soybean and were consequently affected by the asthma epidemics of Barcelona but others did not do so, a case-control study was conducted during 1989, 2 yr after the cessation of asthma epidemics. Patients with asthma admitted in emergency room services during epidemic asthma days (n = 169) were compared with asthma patients admitted in the same services during nonepidemic days and who were never admitted during the epidemics (n = 147). Risk factors other than soybean exposure, namely skin reactivity against at least one common allergen (odds ratio [OR] 3.0, 1.7 to 5.3), age over 64 yr (OR 2.8, 1.4 to 6.0), cigarette smoking at the time of the epidemics (OR 2.3, 1.2 to 2.4), past smoking (OR 1.8, 0.9 to 3.7), and total immunoglobulin E (IgE) higher than 100 IU/ml (OR 1.7, 1.0 to 3.0), were found independently related to epidemic asthma. The role of smoking was especially important for those who had a positive skin reaction and were exposed to soybean dust (OR 7.9, 1.8 to 36.0). In this group, a dose-response pattern with pack-years was observed (p less than 0.01). The present findings suggest a multifactorial process for epidemic asthma, in which atopy and cigarette smoking played an important synergistic role. This has a preventive potential for IgE-related asthma.

Asthma↗
PubMed1990

[Evaluation and significance of circulating immunocomplexes and their correlation with other immunologic parameters in connective tissue diseases].

The presence of circulating immunocomplexes (CIC) was evaluated in several collagen diseases and in a control group of 100 healthy individuals. Three methods were used for their detection: binding to C1q in solid phase, binding to conglutinin in solid phase, and measurement of the serum capacity to solubilize an experimental immunocomplex. In the group of patients with systemic lupus erythematosus (SLE) significant differences were found for the three techniques (p less than 0.001) and also for activity (p less than 0.001). The most sensitive method was binding to C1q. The sensitivity of the three techniques for CIC was very low in the group of patients with systemic sclerosis, and the highest rate of positive results was found with binding to C1q (10%). In the group with hypersensitivity vasculitis and polyarteritis nodosa CIC were found in 71% of cases, more than one method being positive in 50%. The highest sensitivity was obtained with the conglutinin method (48%). In patients with temporal arteritis, significant differences were only found for conglutinin binding method (p less than 0.001), with low rates of positivity.

Adolescent↗
PubMedDate not supplied

Partial characterization of the silk allergens in mulberry silk extract.

Although there have been reports of allergic reactions such as asthma and hypersensitivity pneumonitis to silk allergens (especially in oriental countries), these allergens have not been characterized. We report an in vivo and in vitro study of subjects allergic to silk, as well as a partial characterization of the allergens involved. Forty-one subjects with a clinical history of silk allergy who had asthma, allergic rhinitis or both, and who had a positive intradermal skin test to mulberry silk extract, were evaluated in the study. Four asthmatic subjects with negative skin tests and RASTs to mulberry silk extract were used as controls. RAST specific lgE was present in 37/41 (90%) subjects. SDS-PAGE of mulberry silk extract demonstrated 13 protein bands of less than 21-95 kD. lgE which bound to protein bands was present in 13/32 (41%) sera, twelve of which bound to a single protein with a molecular weight between 35.1 and 50 kD. A pool made with the four control sera did not react with any protein band. The patients allergic to silk showed evidence of sensitivity to mulberry silk extract, both in vivo and in vitro, but sera from 19/32 (59%) subjects did not have antibodies reactive with the mulberry silk extract immunoblot protein bands. The low avidity of the lgE may be responsible for this discrepancy between in vivo and in vitro results.

Adolescent↗