Exposure to grass pollen--but not birch pollen--affects lung function in Swedish children.

Allergic response to pollen is increasing worldwide, leading to high medical and social costs. However, the effect of pollen exposure on lung function has rarely been investigated. Over 1800 children in the Swedish birth cohort BAMSE were lung-function- and IgE-tested at the age of 8 and 16 years old. Daily concentrations for 9 pollen types together with measurements for ozone, NO2 , PM10 , PM2.5 were estimated for the index day as well as up to 6 days before the testing. Exposure to grass pollen during the preceding day was associated with a reduced forced expiratory volume in 8-yr-olds; -32.4 ml; 95% CI: -50.6 to -14.2, for an increase in three pollen counts/m³. Associations appeared stronger in children sensitized to pollen allergens. As the grass species flower late in the pollen season, the allergy care routines might be weakened during this period. Therefore, allergy information may need to be updated to increase awareness among grass pollen-sensitized individuals.

Modulatory effect of 8-iso-PGE2 on platelets.

1. 8-Iso-PGE2 induced either reversible or irreversible aggregation of platelets in human platelet-rich plasma (PRP) or in the suspension of washed platelets (WP). The values of EC50 for irreversible aggregation in PRP and WP were 4 and 2 microM, respectively. 2. In rabbit PRP, 8-iso-PGE2 (0.1-100 microM) itself did not induce or induced only reversible aggregation. 3. 8-Iso-PGE2 (0.1-20 microM) potentiated adenosine diphosphate-(ADP) induced platelet aggregation in both human and rabbit. The same effect also was found for adrenaline-induced platelet aggregation in rabbit. 4. The lower concentrations (0.2-0.5 microM) of 8-iso-PGE2 decreased, and higher concentrations (1-2 microM) increased platelet aggregating factor- (PAF) induced aggregation in human PRP. In rabbit PRP, 8-iso-PGE2 (0.02-200 microM) had only a decreasing effect on PAF-induced aggregation. 5. The results suggest that low concentrations of 8-iso-PGE2 can amplify or weaken platelet aggregation induced by various aggregatory agents.

Comparison of the inhibitory effect of E-prostaglandins in human and rabbit platelet-rich plasma and washed platelets.

1. The anti-aggregatory potency of a number of E-type PGs was compared in human and rabbit platelet-rich plasma (PRP) and washed platelets. The potency of 13,14-dihydro-PGE1 and 5,6-dihydro-PGE3 is significantly higher in human than in rabbit washed platelets, while the potency of 15-keto-13,14-dihydro-PGE1 is higher in rabbit. 2. The potency of PGEs in rabbit PRP is very similar to that of washed platelets, with the exception of 1a,1b-dihomo-PGE2, which is of a significantly lower potency in PRR. 3. In human, 5,6-trans-PGE2, PGE3, and 15-keto-13,14-dihydro-PGE1 are more potent in PRP than in washed platelets. 4. The results indicate that the potency of E-type PGs in human and rabbit platelets is different and plasma can essentially influence the anti-aggregatory effect of PGEs; plasma can either decrease or increase potency.