Siblings, asthma, rhinoconjunctivitis and eczema: a worldwide perspective from the International Study of Asthma and Allergies in Childhood.

BACKGROUND: Associations of larger families with lower prevalences of hay fever, eczema and objective markers of allergic sensitization have been found fairly consistently in affluent countries, but little is known about these relationships in less affluent countries. METHODS: Questionnaire data for 210,200 children aged 6-7 years from 31 countries, and 337,226 children aged 13-14 years from 52 countries, were collected by Phase Three of the International Study of Asthma and Allergies in Childhood (ISAAC). Associations of disease symptoms and labels of asthma, rhinoconjunctivitis and eczema were analysed by numbers of total, older and younger siblings, using mixed (multi-level) logistic regression models to adjust for individual covariates and at the centre level for region, language and national affluence. RESULTS: In both age groups, inverse trends (P < 0.0001) were observed for reported 'hay fever ever' and 'eczema ever' with increasing numbers of total siblings, and more specifically older siblings. These inverse associations were significantly (P < 0.005) stronger in more affluent countries. In contrast, symptoms of severe asthma and severe eczema were positively associated (P < 0.0001) with total sibship size in both age groups. These associations with disease severity were largely independent of position within the sibship and national GNI per capita. CONCLUSIONS: These global findings on sibship size and childhood asthma, rhinoconjunctivitis and eczema suggest at least two distinct trends. Inverse associations with older siblings (observations which prompted the 'hygiene hypothesis' for allergic disease) are mainly a phenomenon of more affluent countries, whereas greater severity of symptoms in larger families is globally more widespread

Estudio y control automático de la operación de extrusión de baldosas cerámicas

The ever-larger tile sizes demanded by the market, the higher quality requirements, and the increasingly similar installation to that of pressed products make it necessary to narrow the tolerance limits of final extruded tile size in order to maintain the product’s competitiveness. The results of this study show that, though mixing water has a great influence on drying shrinkage, it hardly affects extruded tile firing shrinkage. This indicates that control of the water added in the extrusion process is indispensable in order avoid variations in drying shrinkage and, thus, to assure good dimensional stability of the end produc

Validación de dos radioinmuneoensayos clínicos de hormonas tiroideas (T3 y T4) para el análisis de muestras de rata

Para emplear un método de radioinmunoensayo (RIA) en el análisis de muestras de diferente naturaleza de las muestras para las que fue desarrollado y validado, aunque haya identidad antigénica, es necesario validar nuevamente el método para comprobar la ausencia de interferencias analíticas. Se han realizado pruebas de validación (paralelismo, recuperación, precipitación inespecífica) en dos métodos comerciales de RIA para la determinación clínica de hormonas tiroideas (T3 y T4) al aplicarlos al análisis de muestras de suero de rata. El RIA de T4 no muestra paralelismo entre las muestras analizadas y la curva patrón, y la recuperación alcanza valores de 147,5%. De ello deducimos que en el RIA de T4 ensayado hay interferencias analíticas que no permiten la obtención de resultados válidos si se analizan muestras de suero de rata. El RIA de T3 ensayado cumple satisfactoriamente la prueba de paralelismo, la de recuperación, y la precipitación inespecífica es similar en las muestras de suero de rata y en la curva patrón. Por ello el RIA de T3 ensayado es válido para el análisis de muestras de suero de rata.When a radioimmunoasay method is used to analyze samples of a type different than these for wich it was developed, the method needs to be validated to asses the absence of analytical interferences even if antigenic identity exist. We have perfomed validation tests (parallelism, recovery and non specific binding) when applying two comercial RIA methods for clínical determination of thyroid hormones (T3, T4) to rat serum samples. The T 4 shows lack of parallelism between the samples analyzed and the standard curve, the recovery reaches values of 147,5%, so we infer the existence of analytical interferences in the RIA assayed wich precludes obtaining valid results when used to analyze rat serum samples. The T3 RIA assayed fullfills to satisfaction the parallelism test, the average recovery obtained is 95,7% and NSB in rat serum is similar to that of the standard curve, so we conclude this T). RIA is able for the sample analysis of rat serum

Validación de dos radioinmuneoensayos clínicos de hormonas tiroideas (T3 y T4) para el análisis de muestras de rata

When a radioimmunoasay method is used to analyze samples of a type different than these for wich it was developed, the method needs to be validated to asses the absence of analytical interferences even if antigenic identity exist. We have perfomed validation tests (parallelism, recovery and non specific binding) when applying two comercial RIA methods for clínical determination of thyroid hormones (T3, T4) to rat serum samples. The T4 shows lack of parallelism between the samples analyzed and the standard curve, the recovery reaches values of 147,5%, so we infer the existence of analytical interferences in the RIA assayed wich precludes obtaining valid results when used to analyze rat serum samples. The T4 RIA assayed fullfills to satisfaction the parallelism test, the average recovery obtained is 95,7% and NSB in rat serum is similar to that of the standard curve, so we conclude this T). RIA is able for the sample analysis of rat serum.Para emplear un método de radioinmunoensayo (RIA) en el análisis de muestras de diferente naturaleza de las muestras para las que fue desarrollado y validado, aunque haya identidad antigénica, es necesario validar nuevamente el método para comprobar la ausencia de interferencias analíticas. Se han realizado pruebas de validación (paralelismo, recuperación, precipitación inespecífica) en dos métodos comerciales de RIA para la determinación clínica de hormonas tiroideas (T3 y T4) al aplicarlos al análisis de muestras de suero de rata. El RIA de T4 no muestra paralelismo entre las muestras analizadas y la curva patrón, y la recuperación alcanza valores de 147,5%. De ello deducimos que en el RIA de T4 ensayado hay interferencias analíticas que no permiten la obtención de resultados válidos si se analizan muestras de suero de rata. El RIA de T3 ensayado cumple satisfactoriamente la prueba de paralelismo, la de recuperación, y la precipitación inespecífica es similar en las muestras de suero de rata y en la curva patrón. Por ello el RIA de T3 ensayado es válido para el análisis de muestras de suero de rata

The International Study of Asthma and Allergies in Childhood (ISAAC) Phase Three: A global synthesis

This ISAAC Phase Three synthesis provides summarised information on the main findings of the study, regional tables and figures related to the prevalence and severity of current symptoms of asthma, rhinoconjunctivitis and eczema in the main regions of the world. The large number of surveyed children (≈1,200,000), the large number of centres (233) and countries (98) that participated in ISAAC Phase Three makes this study the most comprehensive survey of these diseases ever undertaken. Globally, the prevalence for current asthma, rhinoconjunctivitis and eczema in the 13-14-year age group was 14.1%, 14.6% and 7.3%, respectively. In the 6-7-year age group the prevalence for current asthma, rhinoconjunctivitis and eczema was 11.7%, 8.5% and 7.9%, respectively. The study shows a wide variability in the prevalence and severity of asthma, rhinoconjunctivitis and eczema which occurs not just between regions and countries but between centres in the same country and centres in the same city. This study definitively establishes that the prevalence of those diseases can be very high in non-affluent centres with low socioeconomic conditions. The large variability also suggests a crucial role of local environment characteristics to determine the differences in prevalence between one place and another. Thus, ISAAC Phase Three has provided a large body of epidemiological information on asthma, rhinoconjunctivitis and eczema in childhood from contrasting environments which is expected to yield new clues about the aetiology of those conditions and reasons for their marked global variability. © 2012 SEICAP

Urban environment soundscape evaluation: Milan case study of noise events perceptions by citizens

As one of the main urban environmental pollutants, noise is becoming a real public health concern due to its impact on citizen's well-being. Real-operation noise monitoring can help policy makers in improving the quality of urban environments. To this end, Wireless Acoustic Sensor Networks (WASNs) have been deployed in crowded city centers in both America and Europe. The main application of WASNs is to measure the noise levels from road traffic. Yet, other types of sounds can be found in urban areas, which may also affect citizen's health. Here, we aim to evaluate the citizen's perception of different urban sounds considering their psychoacoustic characteristics, namely loudness, sharpness, roughness, fluctuation strength and tonality. To this end, we have conducted an on-line and off-site listening test using a urban acoustic event dataset collected by WASNs in Milan. The dataset includes seven common urban noises such as sirens, horns, people talking, truck, works, among others. Participants have been asked to rate the level of agreement with adjectives such as loud, shrilling, disturbing, sharp or pleasant. The test responses from one hundred volunteers allow us to gather valuable information about people's perceptions of common urban noises

Orexin-Corticotropin-Releasing Factor Receptor Heteromers in the Ventral Tegmental Area as Targets for Cocaine

Release of the neuropeptides corticotropin-releasing factor (CRF) and orexin-A in the ventral tegmental area (VTA) play an important role in stress-induced cocaine-seeking behavior. We provide evidence for pharmacologically significant interactions between CRF and orexin-A that depend on oligomerization of CRF1 receptor (CRF1R) and orexin OX1 receptors (OX1R). CRF1R–OX1R heteromers are the conduits of a negative crosstalk between orexin-A and CRF as demonstrated in transfected cells and rat VTA, in which they significantly modulate dendritic dopamine release. The cocaine target σ1 receptor (σ1R) also associates with the CRF1R–OX1R heteromer. Cocaine binding to the σ1R–CRF1R–OX1R complex promotes a long-term disruption of the orexin-A–CRF negative crosstalk. Through this mechanism, cocaine sensitizes VTA cells to the excitatory effects of both CRF and orexin-A, thus providing a mechanism by which stress induces cocaine seeking

Which population level environmental factors are associated with asthma, rhinoconjunctivitis and eczema? Review of the ecological analyses of ISAAC Phase One.

The International Study of Asthma and Allergies in Childhood (ISAAC) Phase One showed large worldwide variations in the prevalence of symptoms of asthma, rhinoconjunctivitis and eczema, up to 10 to 20 fold between countries. Ecological analyses were undertaken with ISAAC Phase One data to explore factors that may have contributed to these variations, and are summarised and reviewed here.In ISAAC Phase One the prevalence of symptoms in the past 12 months of asthma, rhinoconjunctivitis and eczema were estimated from studies in 463,801 children aged 13 - 14 years in 155 centres in 56 countries, and in 257,800 children aged 6-7 years in 91 centres in 38 countries. Ecological analyses were undertaken between symptom prevalence and the following: Gross National Product per capita (GNP), food intake, immunisation rates, tuberculosis notifications, climatic factors, tobacco consumption, pollen, antibiotic sales, paracetamol sales, and outdoor air pollution.Symptom prevalence of all three conditions was positively associated with GNP, trans fatty acids, paracetamol, and women smoking, and inversely associated with food of plant origin, pollen, immunisations, tuberculosis notifications, air pollution, and men smoking. The magnitude of these associations was small, but consistent in direction between conditions. There were mixed associations of climate and antibiotic sales with symptom prevalence.The potential causality of these associations warrant further investigation. Factors which prevent the development of these conditions, or where there is an absence of a positive correlation at a population level may be as important from the policy viewpoint as a focus on the positive risk factors. Interventions based on small associations may have the potential for a large public health benefit