<p>The principal aim was to study selected aspects of indoor environment in dwellings and their association with symptoms compatible with the sick building syndrome (SBS). A validated questionnaire was developed specifically for residential indoor investigations, using sociological principles and test procedures. The questionnaire was mailed to 14,243 multi-family dwellings in Stockholm, selected by stratified random sampling. Females, subjects with a history of atopy, those above 65 y, and those in new buildings reported more symptoms. Subjects owning their own dwelling had less symptoms. A multiple regression model was developed, to identify residential buildings with a higher than expected occurrence of SBS. In total, 28.5% reported at least one sign of building dampness in their home (condensation on windows, humidity in the bathroom, mouldy odour, water leakage). All indicators of dampness were related to symptoms, even when adjusting for demographic data, and other building characteristics (OR=2.9-6.0). Associations between symptoms and other building data was evaluated in older houses, built before 1961. Subjects in older buildings with a mechanical ventilation system had fewer symptoms. Heating by electric radiators, and wood heating was associated with an increase of most types of symptoms (OR=1.2-5.0). Multiple sealing measures (OR=1.3), and major reconstruction (OR=1.1-1.9), was associated with an increase of symptoms. The effect of seasonal adapted ventilation (SAV) was studied in a small experimental study. A 20% reduction of ventilation flow from 0.5-0.8 ac/h to 0.4-0.5 ACH during the heating season increased the perception of poor indoor air quality in the dwelling in general, and in the bedroom. In conclusion, low building age, and building dampness in the dwelling are associated with SBS. In older houses, mechanical ventilation is beneficial. The thesis did not support the view that energy saving measures in general is an important risk factor for SBS, but major reconstruction and multiple sealing measures can be risk factor for symptoms. Reducing the outdoor ventilation flow below the current Swedish ventilation standard (0.5 ACH) may increase the perception of impaired air quality. </p>

The principal aim was to study selected aspects of indoor environment in dwellings and their association with symptoms compatible with the sick building syndrome (SBS). A validated questionnaire was developed specifically for residential indoor investigations, using sociological principles and test procedures. The questionnaire was mailed to 14,243 multi-family dwellings in Stockholm, selected by stratified random sampling. Females, subjects with a history of atopy, those above 65 y, and those in new buildings reported more symptoms. Subjects owning their own dwelling had less symptoms. A multiple regression model was developed, to identify residential buildings with a higher than expected occurrence of SBS. In total, 28.5% reported at least one sign of building dampness in their home (condensation on windows, humidity in the bathroom, mouldy odour, water leakage). All indicators of dampness were related to symptoms, even when adjusting for demographic data, and other building characteristics (OR=2.9-6.0). Associations between symptoms and other building data was evaluated in older houses, built before 1961. Subjects in older buildings with a mechanical ventilation system had fewer symptoms. Heating by electric radiators, and wood heating was associated with an increase of most types of symptoms (OR=1.2-5.0). Multiple sealing measures (OR=1.3), and major reconstruction (OR=1.1-1.9), was associated with an increase of symptoms. The effect of seasonal adapted ventilation (SAV) was studied in a small experimental study. A 20% reduction of ventilation flow from 0.5-0.8 ac/h to 0.4-0.5 ACH during the heating season increased the perception of poor indoor air quality in the dwelling in general, and in the bedroom. In conclusion, low building age, and building dampness in the dwelling are associated with SBS. In older houses, mechanical ventilation is beneficial. The thesis did not support the view that energy saving measures in general is an important risk factor for SBS, but major reconstruction and multiple sealing measures can be risk factor for symptoms. Reducing the outdoor ventilation flow below the current Swedish ventilation standard (0.5 ACH) may increase the perception of impaired air quality.

A Imunodeficiência Comum Variável (ICV) e a Deficiência Seletiva de Imunoglobulina A (DIgA) são as imunodeficiências primárias humorais de maior freqüência na população mundial. Ambas as doenças são caracterizadas pela ausência ou redução significativa de imunoglobulinas no soro. Embora diversas anormalidades imunológicas tenham sido associadas a estas doenças, nenhuma hipótese unificadora a respeito das bases moleculares das mesmas foi proposta até o presente momento, sendo que o único defeito comum a todos os pacientes é a falha na diferenciação de células B em plasmócitos e conseqüente secreção de anticorpos. Devido à alta incidência de auto-imunidade e alergia em pacientes com ICV e DIgA, no presente trabalho, visamos analisar por citometria de fluxo a população de linfócitos CD4+ com potencial regulador nesses pacientes, para avaliar se possíveis defeitos quantitativos ou funcionais nesta população reguladora poderiam explicar a alta incidência de doenças auto-imunes ou alérgicas associadas a estas imunodeficiências. / Common Variable Immunodeficiency (CVID) and Selective Immunoglobulin A deficiency (IgAD) are the humoral primary immunodeficiencies with the highest incidence in the population. Both diseases are characterized by the absence or significant reduction of serum immunoglobulins. Although several immunological abnormalities have been associated with these diseases, no unifying hypothesis regarding the molecular basis of CVID and IgAD have been proposed to date, and the only defect common to all patients is the failure in differentiation of B cells into plasma cells and consequent secretion of antibodies. Due to the high incidence of autoimmunity and allergy in patients with CVID and IgAD, in the present work we analyzed by flow cytometry the population of CD4+ lymphocytes with regulatory potential in these patients to assess whether possible quantitative or functional defects in this regulatory population could explain the high incidence of autoimmune diseases or allergic reactions associated with these immunodeficiencies.

Abstract Advances in perinatal treatment practices—such as antenatal corticosteroids, surfactant replacement therapy, and gentler ventilator modalities—have improved the survival of infants born preterm. Consequently, later morbidity and pulmonary outcome for survivors has attracted increasing interest. The incidence of bronchopulmonary dysplasia (BPD) remains high and the condition is manifesting in infants born at earlier gestational weeks than before. This so-called new BPD results from the arrest of alveolar development and is associated with less structural airway injury and interstitial fibrosis than previously. Long-term follow-up data on lung function, lung structure and respiratory morbidity of children treated with modern methods is insufficiently known. We performed a follow-up study of 88 preterm-born children and 88 matched term-born controls at school age. Children born preterm had lower values in lung function measurements than term-born peers. Reductions were most marked in those with a history of BPD. In accordance with the foetal origins hypothesis, children with intrauterine growth restriction (IUGR) had lower lung function than gestation-controls. This indicates that poor growth in utero is an additional burden on pulmonary health. Both IUGR and BPD predicted lower lung function independently. High-resolution computed tomography of the lung was obtained from 21 children with a history of BPD. Structural abnormalities were common, children with severe BPD being most affected. Preterm children were hospitalised more often than controls, mainly because of wheezing disorders. However, BPD did not influence the hospitalisations. According to the meta-analysis of the contemporary data available, the respiratory outcome of children who had only mild BPD may have improved in comparison to old follow-up data, whereas the results for those without BPD or moderate-to-severe BPD have remained remarkably stable despite progress in treatment practices during early life. In conclusion, preterm children had subtle impairments in lung function at school age. Although they were fairly asymptomatic, concern about the possible long-term effects of preterm birth on pulmonary health is justified. It has been proposed that BPD may predispose individuals to an early COPD-like disorder. Preterm children must be protected from any additional burden on respiratory health and should be monitored appropriately for early detection of lung disease. / Tiivistelmä Keskosten tehohoito on kehittynyt viime vuosikymmeninä merkittävästi, ja yhä epäkypsempänä syntyvät keskoset selviävät hengissä syntymän jälkeen. Keskosten pitkäaikainen keuhkosairaus, bronkopulmonaalinen dysplasia (BPD), on perinteisesti johtunut hengityskonehoidon ja happikaasun aiheuttamasta keuhkovauriosta ja johtanut keuhkokudoksen arpeutumiseen. Aiempaa ennenaikaisemmilla keskosilla esiintyy kuitenkin nykyään niin sanottua uutta BPD:tä, jonka ajatellaan johtuvan enemmän keuhkorakkuloiden kehityshäiriöstä kuin hoitojen aiheuttamasta keuhkovauriosta. Selvitimme, miten nykyaikaisilla menetelmillä hoidettujen keskosten keuhkojen rakenne ja toiminta kehittyvät kouluikään mennessä. Seurantatutkimukseemme osallistui 88 ennenaikaisena syntynyttä, kouluikään ehtinyttä lasta ja 88 täysiaikaisena syntynyttä, kaltaistettua verrokkia. Keskosena syntyneiden lasten keuhkofunktio oli kouluiässä huonompi kuin täysiaikaisena syntyneiden verrokkien. Alhaisin keuhkofunktio oli niillä keskosena syntyneillä lapsilla, jotka olivat sairastaneet vastasyntyneenä BPD:n. Myös kohdunsisäiseen kasvuhäiriöön (intrauterine growth restriction, IUGR) liittyi alentunut keuhkofunktio. BPD ja IUGR ennustivat alentunutta keuhkofunktiota toisistaan riippumatta. Tutkimuksessa tehtiin myös keuhkojen ohutleiketietokonekuvaus 21 keskoselle, jotka olivat sairastaneet BPD:n. Lähes kaikilla havaittiin poikkeavia löydöksiä – eniten niillä, joilla oli ollut vastasyntyneenä BPD:n vaikea tautimuoto. Keskosina syntyneet joutuivat kahden ensimmäisen vuoden aikana verrokkeja useammin sairaalahoitoon. Yleisimpiä syitä olivat hengityksen vinkumista aiheuttavat taudit kuten ilmatiehyttulehdus, ahtauttava keuhkoputkitulehdus tai akuutti astmakohtaus. Vastasyntyneenä sairastettu BPD ei kuitenkaan lisännyt todennäköisyyttä joutua sairaalahoitoon. Tutkimuksessa tehtiin myös meta-analyysi nykyaikaisilla menetelmillä hoidettujen keskosten keuhkofunktiosta: lievää BPD:tä sairastavien tulokset näyttävät parantuneen, kun taas keskivaikeaa tai vaikeaa tautimuotoa sairastavien ja ilman BPD:tä selvinneiden keuhkofunktio ei ole muuttunut uusien hoitojen myötä. Yhteenvetona voidaan todeta, että keskosten keuhkojen toimintakyky on jonkin verran alentunut täysiaikaisiin verrattuna. Lievästi alentunut keuhkofunktio ei kuitenkaan yleensä aiheuttanut koululaisille oireita. Keskosena syntyneiden lasten hengityselinten toimintaa on syytä seurata, sillä niin sanotun uuden BPD:n pitkäaikaisesta ennusteesta ei ole vielä tietoa.

L'asma és una malaltia d'etiologia complexa, formada per factors genètics i ambientals, on la interrelació de ambdós factors mitjançant interaccions gen-ambient juga un paper clau. L'objectiu d'aquesta tesi ha sigut aprofundir en el coneixement del paper dels polimorfismes genètics, i la seva interacció amb factors ambientals, en la ocurrència d'asma, atòpia i hiperreactivitat bronquial. Aquest objectiu ha estat desenvolupat a través de la replicació de variants genètiques prèviament identificades, l'avaluació d'interaccions gen-ambient i la identificació de nous gens de susceptibilitat mitjançant un disseny basat en el genotipatge de variants genètiques all llarg del genoma en pools d'ADN. La tesi ha estat majoritàriament duta a terme dins l'estudi European Community Respiratory Health Survey (ECRHS) que està comprès per 5.000 individus seguits durant 9 anys, pels quals es disposa d'un qüestionari complet sobre símptomes respiratoris, avaluacions clíniques, informació sobre exposicions ambientals i mostres de ADN. Aquesta tesi a replicat l'associació del polimorfismes dels gens TNFA i NPSR1 amb asma. A més s'han establert les interaccions entre TNFA i obesitat, NQO1 i contaminació atmosfèrica, i NPSR1 i edat d'inici d'asma. L'anàlisi de pools d' ADN ha permès associar la regió on es situa el gen SGK493 amb atòpia. Aquesta tesi contribueix al coneixement de l'etiologia d'asma amb la identificació i replicació d'associacions genètiques i interaccions gen-ambient. / Asthma is a disease with a complex etiology, involving multiple genetic and environmental factors, and with an important role of the interplay of these factors through gene-environment interactions. In this thesis I aimed to advance our knowledge on the importance of genetic polymorphisms and their interaction with environmental data for the occurrence of asthma and related phenotypes (atopy and bronchial hyperreactivity). This objective was developed through the replication of genetic associations previously reported, the assessment of gene-environment interactions and the identification of new susceptibility genes using genome-wide analysis based on a pooling DNA strategy. The thesis was, mostly, performed within the European Community Respiratory Health Survey (ECRHS). This cohort has information and DNA samples from approximately 5,000 adult subjects followed-up for 9 years, with extensive questionnaires on respiratory symptoms, clinical evaluations and information on environmental exposures. This thesis replicates previous effects on asthma of polymorphisms in TNFA and NPSR1 genes. In addition, interactions have been established between TNFA and obesity, NQO1 and air-pollution, and NPSR1 and age at onset of asthma. The approach based on genome-wide analysis of DNA pools identified the SGK493 region being associated with atopy. This thesis contributes to the understanding of the etiology of asthma through the identification and replication of genetic associations and gene-environment interactions.