RESUMO
OBJECTIVE: To assess the prevalence of asthma symptoms and their association with sensitisation to eight allergens and bronchial hyperresponsiveness (BHR) to methacholine. SETTING: A random sample of 1232 adults, aged 22 to 28 years, studied in a Chilean semi-rural area. DESIGN: A cross-sectional design for the purpose of this analysis. RESULTS: The prevalence of wheeze was 27.4% (95%CI 24.9-29.9) and waking with breathlessness 13.7% (95%CI 11.8-15.6), higher than the results of a multi-centre European study. Only 7.8% (95%CI 6.3-9.3) had a positive BHR (< or =8 mg/ml) and 26.3% (95%CI 23.8-28.8) were atopic. The Youden index of asthma symptoms in non-atopic subjects varied from 0.184 to 0.259 when using BHR as gold standard for asthma, and increased from 0.379 to 0.504 among those with positive atopy. Only 4.5% reported asthma, and the Youden index was slightly higher in comparison to the asthma symptom groups. CONCLUSION: The prevalence of asthma symptoms in young adults was high, but only a small proportion of these were sensitised or had a positive BHR. We believe that aetiological studies of asthma should analyse subjects with asthma symptoms separately from those with positive atopic status or positive BHR.
Assuntos
Asma/epidemiologia , Hiper-Reatividade Brônquica/epidemiologia , Hipersensibilidade Imediata/epidemiologia , Adulto , Chile/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Prevalência , Saúde da População RuralRESUMO
An active regional transplantation program established in the southern region of Chile has allowed the incorporation of ethnic minorities particularly Mapuche living in this geographic area in the development of a histocompatibility database. To identify possible differences in the human leukocyte (HLA) antigen distribution in Chilean Mapuche compared with non-Mapuche, we reviewed 442 HLA tissue-typing studies. Seventy-eight of 309 recipients (25%) and 18 of 133 donors (13%) were Mapuche. Among recipients, Mapuche people showed a significantly higher frequency of the HLA antigens, A28, B16, DR4, and DR8, and a lower one for A19, B15, and DR1 (P < .05) compared with non-Mapuche individuals. A particularly higher frequency of the haplotype A28, -B16, -DR4 was also evidenced in Mapuche. Besides, these recipients showed a higher frequency of the allele -DR4 when compared with Mapuche donors. A greater frequency of some histocompatibility antigens in patients with chronic renal disease might be attributed to allelic concentration due to a high index of endogamy, but a possible association with the development of progressive renal disease cannot be ignored, especially when a higher prevalence of DR4 was observed among Mapuche recipients.
Assuntos
Antígenos HLA/sangue , Transplante de Rim/imunologia , Chile , Antígenos HLA-A/sangue , Antígenos HLA-B/sangue , Antígenos HLA-DR/sangue , Haplótipos , Teste de Histocompatibilidade , Humanos , Grupos Populacionais , Doadores de TecidosRESUMO
Intravenous infusion of free fatty acid (FFA) 20 mg.kg-1.min-1 produces pulmonary edema, hypoxemia, hyperventilation and increase in the alveolar surfactant content in rabbits in less than 15 min. We tried to study the role of leukotrienes (LT) and the effects of PGI2 in pulmonary response to FFA. We used Piriprost an inhibitor of LT synthesis or Epoprostenol (Prostacyclin: PGI2) in 4 series of rabbits treated with FFA or its vehicle. Piriprost given as an aerosol (0.1% W/W in THAM) scarcely modified the morphofunctional changes induced by FFA. The only pulmonary effect prevented by Piriprost was the increase in surfactant content (disaturated phosphatidylcholine: DSPC) in broncho-alveolar lavage gluid (BAL). PGI2 administered in a dose of 0.1 micrograms.kg-1.min-1 5 minutes prior to a 15 min infusion of FFA was also unable to prevent most of the effects of FFA on the lung. Only the increase in DSPC in BAL was prevented by PGI2. Some animals received a smaller dose of FFA, because they died earlier. Piriprost, as well as PGI2, shortened the survival time of rabbits treated with FFA. This decrease in the survival rate of animals treated with FFA could account for the lack of increase in DSPC post-FFA. Since other morphofunctional changes induced by FFA were scarcely modified by both Piriprost or PGI2, our results suggest that it is unlikely that either leukotrienes on PGI2 may have a significant effect on pulmonary disturbances induced by FFA.
Assuntos
Epoprostenol/análogos & derivados , Epoprostenol/farmacologia , Ácidos Graxos não Esterificados/farmacologia , Leucotrienos/fisiologia , Pulmão/fisiologia , Tromboxano A2/farmacologia , Animais , Epoprostenol/administração & dosagem , Hemodinâmica/efeitos dos fármacos , Infusões Intravenosas , Pulmão/efeitos dos fármacos , Masculino , CoelhosRESUMO
Aspiration of gastric contents to the lung is a cause of Adult Respiration Distress syndrome. We studied the effects of endotracheal instillation of hydrochloric acid (2 ml/kg, 0.1 N solution) in anesthetized rats who were sacrificed 4 or 48 hr later. A control group received 0.9% saline solution instead. Total protein, phospholipids, disaturated phosphatidylcholine (DSPC) and number of cells were determined in the bronchoalveolar lavage fluid. Histologic studies were performed in one rat in each group. HCl caused edema and inflammatory reaction characterized by a rise in protein and cells in the bronchoalveolar fluid 48 hr after endotracheal instillation. This was associated with an increase in total phospholipid and in DSPC. Therefore, the inflammatory response to HCl is associated to an increase in alveolar surfactant 48 hr after instillation.