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The swelling‐activated outwardly rectifying Cl− current (ICl(swell)) recorded in T84 human intestinal cells was completely blocked by 10 μM tamoxifen, while 300 μM Cd2+ had no effect. A ClC‐2‐like, inwardly rectifying Cl− current was activated after strong hyperpolarization in T84 cells. This current was completely inhibited by 300 μM Cd2+, unaffected by 10 μM tamoxifen, and its magnitude increased slightly in response to cell swelling under hyposmotic conditions. However, the swelling‐dependent modulation occurred only after prior activation by hyperpolarizing voltages. T84 cells behaved initially close to perfect osmometers in response to changes in external osmolalities between +20 and ‐30 %. The cells underwent full regulatory volume decrease (RVD) within 16 min when exposed to 30 or 10 % hyposmotic shocks. Pharmacological tools were used to determine the anionic pathway(s) involved in RVD in T84 cells. Tamoxifen (10 μM), 1,9‐dideoxyforskolin (DDFSK; 100 μM) and 4,4′‐diisothiocyanatostilbene‐2,2′‐disulphonic acid (DIDS; 100 μM) blocked RVD while 300 μM Cd2+ had no effect upon RVD following a 30 % hyposmotic shock. The RVD response was similarly unaffected by Cd2+ when cells were exposed to a smaller (10 %) hyposmotic shock. In conclusion, these data show that the anionic pathway primarily activated by cell swelling and relevant to RVD in T84 cells is the tamoxifen‐, DDFSK‐ and DIDS‐sensitive ICl(swell) and not the hyperpolarization‐activated, Cd2+‐sensitive Cl− current associated with the ClC‐2 Cl− channel.

Background The Global Asthma Network (GAN), by using the International Study of Asthma and Allergies in Childhood (ISAAC) methodology, has updated trends in prevalence of symptoms of childhood allergic diseases, including non‐infective rhinitis and conjunctivitis (‘rhinoconjunctivitis’), which is reported here. Methods Prevalence and severity of rhinoconjunctivitis were assessed by questionnaire among schoolchildren in GAN Phase I and ISAAC Phase I and III surveys 15–23 years apart. Absolute rates of change in prevalence were estimated for each centre and modelled by multi‐level linear regression to compare trends by age group, time period and per capita national income. Results Twenty‐seven GAN centres in 14 countries surveyed 74,361 13‐ to 14‐year‐olds (‘adolescents’) and 45,434 6‐ to 7‐year‐olds (‘children’), with average response proportions of 90% and 79%, respectively. Many centres showed highly significant (p < .001) changes in prevalence of rhinoconjunctivitis in the past year (‘current rhinoconjunctivitis’) compared with ISAAC. The direction and magnitude of centre‐level trends varied significantly (p < .001) both within and between countries. Overall, current rhinoconjunctivitis prevalence decreased slightly from ISAAC Phase III to GAN: −1.32% per 10 years, 95% CI [−2.93%, +0.30%] among adolescents; and −0.44% [−1.29%, +0.42%] among children. Together, these differed significantly (p < .001) from the upward trend within ISAAC. Among adolescents, centre‐level trends in current rhinoconjunctivitis were highly correlated with those for eczema symptoms (rho = 0.72, p < .0001) but not with centre‐level trends in asthma symptoms (rho = 0.15, p = .48). Among children, these correlations were positive but not significant. Conclusion Symptoms of non‐infective rhinoconjunctivitis among schoolchildren may no longer be on the increase globally, although trends vary substantially within and between countries.

The International Study of Asthma and Allergies in Childhood (ISAAC) uses standardized symptombased questionnaires to describe the prevalence of symptoms of asthma, rhinoconjunctivitis and eczema in children worldwide. Three governorates in the Syrian Arab Republic (Aleppo, Lattakia and Tartous) participated in ISAAC phase 3 in 2001-03. Adolescents in the 13-14 year age group and parents of the 6-7-year-old children completed the questionnaire about asthma symptoms. The prevalence of current symptoms of asthma (wheezing in the last 12 months) in different centres ranged from 4.7% to 5.7% for 6-7-year-olds and 3.9% to 6.5% for 13-14-year-olds. In 13-14-year-olds the prevalence of severe speech-limiting wheeze was 2.0%-3.5%, of rhinoconjunctivitis was 8.6%-14.6% and of eczema was 3.3%-4.2%. Étude internationale de l'asthme et des allergies de l'enfant : phase 3 en République arabe syrienne RÉSUMÉ L'étude internationale de l'asthme et des allergies de l'enfant (ISAAC) utilise des questionnaires standardisés basés sur les symptômes de l'asthme, de la rhinoconjonctivite et de l'eczéma touchant les enfants dans le monde entier. Entre 2001 et 2003, trois gouvernorats de la République arabe syrienne (Alep, Lattaquié et Tartous) ont participé à la phase 3 de l'ISAAC. Les adolescents appartenant à la tranche d'âge 13-14 ans et les parents d'enfants âgés de 6 à 7 ans ont rempli le questionnaire concernant les symptômes de l'asthme. La prévalence des symptômes actifs de l'asthme (sifflement respiratoire au cours des 12 derniers mois) dans différents hôpitaux était comprise entre 4,7 % et 5,7 % pour les enfants âgés de 6 à 7 ans et entre 3,9 % et 6,5 % pour ceux âgés de 13 à 14 ans. Au sein du groupe des 13-14 ans, la prévalence du sifflement respiratoire sévère limitant la parole était comprise entre 2,0 % et 3,5 %, celle de la rhinoconjonctivite variait entre 8,6 % et 14,6 % et celle de l'eczéma oscillait entre 3,3 % et 4,2 %. ‫املتوسط‬ ‫لرشق‬ ‫الصحية‬ ‫املجلة‬ ‫عرش‬ ‫السادس‬ ‫املجلد‬ ‫السابع‬ ‫العدد‬ 711

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