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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

Melatonin and thyroid hormones in the cold and in darkness:association with mood and cognition

Pääkkönen, T. (Tiina) 16 February 2010 (has links)
Abstract The purpose of the study was to examine the cold-induced effects on pineal and thyroid hormones, as well as the associations of these hormones with psychological performance and to determine how psychological performance could be affected by demographic, anthropometric, physiological or biochemical measures during cold acclimatisation. The feasibility of urinary melatonin (MT), rather than 6-sulphatoxymelatonin (aMT6s), as an indicator of MT secretion was also examined. In the laboratory study, seasonal cold acclimatisation, its effects on hormones and their associations with mood and cognition were assessed in 15 young urban subjects exposed to cold in winter or summer in bright or dim light. In the field study, the associations of mood and cognition with demographic, anthropometric, physiological and biochemical measures were determined in healthy, euthyroid subjects (n = 133) in Antarctica in the beginning and at the end of summer and winter seasons. In both seasons, simple task performance was consistently impaired in the cold in experimental and field conditions. In complex tasks, negative, positive and mixed effects were observed. In the experimental study, serum MT and thyroid hormone levels were positively associated with mood. MT was negatively associated with simple task performance. Free triiodothyronine (T3) and thyrotropin (TSH) had mixed effects on simple task performance. TSH was positively associated with complex task performance. In the field study, higher age was associated with impaired cognition, especially in complex task performance. Total T3 was positively associated with mood and total thyroxine (T4) with complex task accuracy. Both urinary MT and aMT6s were good indicators of MT secretion, but the variation was smaller for MT. In conclusion, the associations of serum MT, TSH and thyroid hormone levels with mood and cognition found in experimental and field conditions are consistent with the psychological changes associated with the onset and consequent stages of the previously established polar T3 syndrome. In the field study, cognition and mood were associated with subject’s age and gender, which seemed to affect the physiological changes during acclimatisation to cold and darkness in Antarctica. / Tiivistelmä Tutkimuksen tarkoituksena oli selvittää kylmäaltistuksen aiheuttamia muutoksia käpy- ja kilpirauhasen hormonien tasoissa, hormonien yhteyttä psyykkiseen toimintakykyyn sekä demografisten, antropometristen, fysiologisten ja biokemiallisten tekijöiden yhteyttä psyykkiseen toimintakykyyn kylmäakklimatisaation aikana. Lisäksi verrattiin virtsan melatoniinin (MT) ja 6-sulfatoksimelatoniinin (aMT6s) soveltuvuutta MT-erityksen kuvaajina. Laboratoriotutkimuksessa selvitettiin talveen liittyvää kylmäsopeutumista, sen vaikutusta hormonitasoihin ja näiden yhteyttä mielialaan ja älylliseen toimintakykyyn 15 nuorella miehellä, jotka altistettiin kylmälle talvella ja kesällä sekä kirkkaassa että hämärässä valossa. Kenttäkokeessa Antarktiksella selvitettiin mielialan ja älyllisen toimintakyvyn sekä demografisten, antropometristen, fysiologisten ja biokemiallisten tekijöiden välistä yhteyttä terveillä henkilöillä (n =  133) kesä- ja talvikauden alussa ja lopussa. Suoriutuminen yksinkertaisista tehtävistä huononi kylmässä kesällä ja talvella sekä laboratorio- että kenttäoloissa. Kylmä vaikutti monimutkaisista tehtävistä suoriutumiseen vaihtelevasti. Laboratoriotutkimuksessa seerumin MT- ja kilpirauhashormonitasot korreloivat positiivisesti mielialan kanssa. MT korreloi negatiivisesti yksinkertaisista tehtävistä suoriutumisen kanssa. Vapaa trijodotyroniini (T3) ja tyrotropiini (TSH) korreloivat vaihtelevasti yksinkertaisista tehtävistä suoriutumisen kanssa. TSH korreloi positiivisesti monimutkaisista tehtävistä suoriutumisen kanssa. Kenttätutkimuksessa korkeampi ikä oli yhteydessä huonontuneeseeen älylliseen toimintakykyyn erityisesti monimutkaisissa tehtävissä. T3:n kokonaismäärä korreloi positiivisesti mielialan ja tyroksiinin (T4) kokonaismäärä monimutkaisista tehtävistä suoriutumisen kanssa. Sekä virtsan MT että aMT6s olivat hyviä MT-erityksen mittareita, mutta MT:ssa vaihtelu oli pienempää. Laboratorio- ja kenttäolosuhteissa havaitut MT:n, TSH:n ja kilpirauhashormonien yhteydet mielialaan ja älylliseen toimintakykyyn vahvistavat aiemmin havaittuja tuloksia polaarisen T3 -oireyhtymän synnystä ja oireyhtymän eri vaiheisiin liittyvistä psyykkisistä muutoksista. Kenttätutkimuksessa mieliala ja älyllinen toimintakyky olivat yhteydessä koehenkilön ikään ja sukupuoleen, jotka puolestaan voivat vaikuttaa fysiologisiin muutoksiin kylmään ilmastoon ja pimeyteen sopeutumisen aikana.
132

Exposure to environmental tobacco smoke, animals and pollen grains as determinants of atopic diseases and respiratory infections

Hugg, T. (Timo) 16 September 2009 (has links)
Abstract Little is known about a) the differences in allergic and respiratory diseases between the Finnish and Russian populations, and the environmental factors associated with those differences, and b) exposure to pollen grains indoors and the efficiency of penetration of pollen from outdoor to indoor air. This thesis is based on a cross-sectional population-based epidemiological study conducted in Imatra (Finland) and Svetogorsk (Russia) in 2003 and a rotorod-type-sampler-based pollen study conducted in the province of South Karelia (Finland) between 2003 and 2004. The prevalence of allergic diseases was higher among Finnish than Russian schoolchildren. The symptoms among allergic children were more severe, and the occurrence of respiratory infections was in general more frequent in Russia than in Finland. In the logistic regression analyses the risk of asthma was particularly related to high maternal smoking exposure, and the risk of the common cold was related to high combined parental smoking during infancy (adjusted OR 1.83, 95% CI 1.06–3.17) in Finnish children. Among Russian children, allergic conjunctivitis was related to maternal smoking, while the common cold was inversely related to paternal and parental smoking (0.60, 0.37–0.98 and 0.31, 0.11–0.83, respectively) during the study period. The risk of asthma was inversely related to any indoor dog-keeping in Finland (0.35, 0.13–0.95), whereas in Russia the risk of asthma was increased in relation to combined indoor cat exposure during infancy and the study period (4.56, 1.10–18.91). The concentrations of pollen grains decreased from abundant (0–855 pollen grains per cubic meter, pg/m3) to low (0–3 pg/m3), when moving from outdoors to indoors and further. The differences in diseases and symptoms in these two closely related populations could be ascribed to differences in culture, exposures, diagnostic criteria and treatment. The concentrations of pollen in indoor air during the flowering period were mostly on a level high enough to cause reactions in only the most sensitive subjects. The results suggest that more efforts should be directed to reducing parental smoking, to studying the role and effects of nationally different animal exposures in childhood, and to assessing the importance of different penetration routes of pollen grains. / Tiivistelmä Suomen ja Venäjän välisistä allergioiden ja hengitystietulehdusten esiintymiseroista ja esiintymiseen vaikuttavista ympäristötekijöistä tiedetään varsin vähän. Myös tutkimuksia siitepölyille altistumisesta sisätiloissa ja siitepölyjen tunkeutumiskyvystä ulkoilmasta sisäilmaan on niukasti. Tutkimus yhdistää sekä lääketieteellisen että luonnontieteellisen tutkimusalan tutkimustraditiot sekä atooppisten sairauksien ja/tai hengitystietulehdusten tärkeimpien määrittäjien tarkastelun yhdeksi tutkimuskokonaisuudeksi. Väestö- ja kyselylomakepohjainen poikkileikkaustutkimus toteutettiin Suomen ja Venäjän rajan molemmin puolin sijaitsevissa Imatran ja Svetogorskin kaupungeissa vuonna 2003. Tutkimusväestö koostui 512 suomalaisesta ja 581 venäläisestä 7–16-vuotiaasta koululaisesta (osallistumisaste 79 %). Rotorod-tyyppisen keräimen käyttöön perustuva siitepölytutkimus toteutettiin erilaisissa ulko- ja sisätiloissa Lappeenrannan ja Imatran kaupungeissa, Rautjärven kunnassa ja valtatie 6:lla vuosina 2003 ja 2004. Atooppisten sairauksien esiintyvyys oli runsaampaa suomalaisten koululaisten keskuudessa. Sitä vastoin allergisten lasten kokemat oireet olivat voimakkaampia ja hengitystietulehdusten esiintyvyys oli runsaampaa venäläisten koululaisten keskuudessa. Astmariski kytkeytyi erityisesti äidin runsaalle tupakoinnille altistumiseen raskauden (vakioitu OR 3.51, 95 % luottamusväli 1.00–12.3), ensimmäisen elinvuoden (3.34, 1.23–9.07) ja tutkimuksen aikana (3.27, 1.26–8.48). Nuhakuumeen riski oli suurentunut suomalaisten koululaisten keskuudessa, jotka olivat altistuneet molempien vanhempien runsaalle tupakoinnille ensimmäisen elinvuoden aikana (1.83, 1.06–3.17). Äidin tupakoinnille ensimmäisen elinvuoden (4.53, 1.49–13.8) ja tutkimuksen aikana (2.82, 1.07–7.44) altistuneilla venäläisillä oli suurentunut allergisen silmän sidekalvotulehduksen riski. Tutkimuksen aikainen isän ja vanhempien tupakointi vähensi nuhakuumeen riskiä (0.60, 0.37–0.98; 0.31, 0.11–0.83) Venäjällä. Suomessa koiranpito sisätiloissa vähensi astmariskiä (0.35, 0.13–0.95), vastaavasti Venäjällä raskauden jälkeinen sisätiloissa tapahtuva kissa-altistus lisäsi koululaisten astmariskiä (4.56, 1.10–18.91). Siitepölyjen pitoisuudet pienenivät siirryttäessä ulkoa (0–855 siitepölyhiukkasta ilmakuutiossa; sp/m3) sisätiloihin (0–17 sp/m3). Ympäristöaltisteisiin ja sairauden ennusteeseen vaikuttavat sekä kansallinen kulttuuri ja vakiintuneet tavat, että erot diagnosointikriteereissä, yleisessä tautitietoisuudessa ja lääkkeiden saatavuudessa. Näin ollen altisteiden voimakkuus ja kesto sekä terveysvaikutukset voivat vaihdella merkittävästi lähellä toisiaan sijaitsevien alueiden välillä. Siitepölypitoisuudet sisätiloissa olivat pääosin tasolla, jolle altistuminen aiheuttaa oireita vain kaikkein herkimmille allergisille. Tutkimuksen tulosten mukaan lisää voimavaroja tulisi suunnata passiiviselle tupakoinnille altistumisen vähentämiseen erityisesti yksilökehityksellisesti herkkien varhaisvaiheiden aikana, kansallisten eläinaltistuserojen terveysvaikutusten selvittämiseen sekä siitepölyjen erilaisten kulkeutumisreittien merkityksen tutkimiseen.
133

Évolution du cancer du testicule en Europe : expositions environnementales et professionnelles / Burden of testicular cancer in Europe : environmental and occupational exposures

Le Cornet, Charlotte 10 December 2014 (has links)
Les tumeurs germinales du testicule (TGT) représentent le cancer le plus fréquent chez les hommes Européens âgés de 15 et 39 ans. L'incidence a doublé dans la plupart des pays Européens depuis 30 ans. Cette augmentation rapide, les variations géographiques d'incidence et les études chez les populations migrantes suggèrent un rôle des facteurs environnementaux dans le développement des TGT. Cette thèse propose de contribuer à l'amélioration des connaissances concernant l'évolution du TGT en clarifiant l'impact des expositions environnementales et professionnelles, notamment pendant la période prénatale. Les objectifs principaux sont de: 1. Prédire l'incidence du TGT jusqu'en 2025 en estimant la part d'augmentation due aux changements démographiques afin d'obtenir une estimation de l'augmentation due aux risques. 2. Faire un bilan de l'état des connaissances sur l'association entre les expositions environnementales et professionnelles et le développement du TGT dans une revue systématique de littérature 3. Investiguer l'association entre l'exposition parentale professionnelle aux pesticides en période prénatale et le TGT parmi la descendance Les résultats montrent que l'incidence du TGT continue d'augmenter, mettant en avant un fort impact environnemental dans l'évolution du TGT. Néanmoins, la revue de littérature ne permettait pas d'identifier de facteurs de risque environnementaux avérés, mais montrait un manque d'études investiguant les expositions prénatales sur le risque de TGT. L'étude NORD-TEST menée sur les données de registre de quatre pays nordiques est l'étude la plus puissante à ce jour et ne montre aucune association entre l'exposition parentale professionnelle aux pesticides en période prénatale et le TGT / Testicular germ cell tumours (TGCT) are the most common cancer diagnosed among young European men aged between 15 and 39 years. TGCT incidence rates have doubled in most European countries over the last 30 years. This rapid increase in incidence, the geographical variations and the studies in migrant populations suggest a role of environmental factors in TGCT aetiology. This thesis aims to contribute to the knowledge of TGCT evolution by studying the impact of environmental and occupational exposures, especially during the prenatal period. The objectives are: 1. To estimate the proportion of the increased incidence due to overall changes in risk patterns compared to the proportion due to demographic changes, by predicting the future testicular cancer trends in Europe 2. To summarize and evaluate the current knowledge on environmental and occupational exposures related to TGCT risk by means of a systematic literature review 3. To investigate the association between the prenatal parental occupational exposure to pesticides and TGCT risk in the offspring. The results show that the TGCT incidence continues to increase, supporting an environmental impact on TGCT evolution. From the epidemiological literature to date no specific environmental risk factors emerge; however, there have clearly been a lack of studies investigating prenatal exposures on TGCT risk. The NORD-TEST study, based on registry data from four Nordic countries, is the largest study to date. No association was found between parental occupational exposure to pesticides during prenatal period and TGCT risk
134

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

Asher, M Innes, Stewart, Alistair W, Mallol, Javier, Montefort, Stephen, Lai, Christopher K W, Aït-Khaled, Nadia, Odhiambo, Joseph, Chiarella, Pascual, The ISAAC Phase One Study Group 21 January 2010 (has links)
Revisión por pares
135

Are Environmental Factors for Atopic Eczema in ISAAC Phase Three due to Reverse Causation?

Rutter, Charlotte E, Silverwood, Richard J, Williams, Hywel C, Ellwood, Philippa, Asher, Innes, Garcia-Marcos, Luis, Strachan, David P, Pearce, Neil, Langan, Sinéad M, Chiarella, Pascual, ISAAC Phase Three Study Group 01 May 2019 (has links)
Some previously described environmental associations for atopic eczema may be due to reverse causation. We explored the role of reverse causation by comparing individual- and school-level results for multiple atopic eczema risk factors. The International Study of Asthma and Allergies in Childhood (i.e, ISAAC) Phase Three surveyed children in schools (the sampling unit) regarding atopic eczema symptoms and potential risk factors. We assessed the effect of these risk factors on atopic eczema symptoms using mixed-effect logistic regression models, first with individual-level exposure data and second with school-level exposure prevalence. Overall, 546,348 children from 53 countries were included. At ages 6–7 years, the strongest individual-level associations were with current paracetamol use (odds ratio [OR] = 1.45, 95% confidence interval [CI] = 1.37–1.54), which persisted at school-level (OR = 1.55, 95% CI = 1.10–2.21), early-life antibiotics (OR = 1.41, 95% CI = 1.34–1.48), and early-life paracetamol use (OR = 1.28, 95% CI = 1.21–1.36), with the former persisting at the school level, whereas the latter was no longer observed (OR = 1.35, 95% CI = 1.00–1.82 and OR = 0.94, 95% CI = 0.69–1.28, respectively). At ages 13–14 years, the strongest associations at the individual level were with current paracetamol use (OR = 1.57, 95% CI = 1.51–1.63) and open-fire cooking (OR = 1.46, 95% CI = 1.33–1.62); both were stronger at the school level (OR = 2.57, 95% CI = 1.84–3.59 and OR = 2.38, 95% CI = 1.52–3.73, respectively). Association with exposure to heavy traffic (OR = 1.31, 95% CI = 1.27–1.36) also persisted at the school level (OR = 1.40, 95% CI = 1.07–1.82). Most individual- and school-level effects were consistent, tending to exclude reverse causation. / Revisión por pares
136

Estimativa  da carga de exposição diária a material particulado em indivíduos expostos a poluição ambiental de origem veicular / Daily exposure load estimate of particulate matter in individuals exposed to environmental vehicular pollution

Cozza, Izabela Campos 04 November 2013 (has links)
Introdução: O uso de amostradores individuais de poluentes e a medida da ventilação (Ve) tem sido avaliados para estimar a dose de exposição a poluição. Por ser a Ve uma medida de difícil mensuração em campo, tem-se estimado a Ve a partir da frequência cardíaca (FC) utilizando equações de regressão construídas em teste de esforço cardiopulmonar (TECP). Entretanto, ainda persistem dúvidas quanto à sua aplicabilidade para estimar a Ve em indivíduos com características semelhantes, porem que não realizaram o TECP. O objetivo do estudo foi avaliar modelos para a estimativa da Ve a partir da FC, construído a partir de TECP, e testar sua aplicabilidade com o uso de medidas da FC em campo, em diferentes grupos expostos a poluentes. Métodos: Avaliados 60 homens, não tabagistas, 33 que trabalham em vias públicas (Grupo Via Publica - GVP), 17 que trabalham em um Parque (Grupo Parque - GP) e 10 outros participantes (Grupo teste - GT) para validação dos modelos utilizados. Todos tiveram registros da FC e da concentração de MP2,5, durante 24 horas, e realizaram TECP. Resultados: Foram encontradas grandes variações nas equações de regressão entre os indivíduos, e entre os grupos avaliados, mas o emprego de equações de regressão médias, para estimar a carga de exposição com registro da FC de 24 horas em campo revelou-se adequado para situações de FC média abaixo de 80 bpm. Conclusão: Equações individuais estimam de maneira mais precisa a Ve e a carga inalada de poluentes, mas equações construídas em um grupo de indivíduos podem ser empregadas para estimar a Ve em atividades onde a FC média não é elevada, como ocorre com a maioria das situações habituais de atividades de vida diárias / Background: To evaluate the degree of exposure to air pollutants, ventilation (Ve) measurements and individual pollutant sampler have been used. Given that Ve is difficult to measure in field studies, it has been estimated based on the heart rate (HR) using regression equations that were built with cardiopulmonary exercise test (CPET) results. However, doubt still exists as to its applicability to estimate Ve in groups of individuals who did not perform the CPET. The purpose of this study was to evaluate different models for estimating Ve based on HR, constructed from CPET, and to test the models\' applicability using HR measurements in the field, in different groups exposed to pollutants. Methods: We evaluated 60 men, nonsmokers: 33 public streets workers (Public Street Group - GPS), 17 park workers (Park Group - GP), and 10 other participants (Test Group - GT) for model validation. All subjects underwent HR and PM2.5 concentration recording throughout 24 hours and CPET. Results: We found wide variations in the regression equations between individuals and the assessed groups. Nonetheless, the use of average regression equations to estimate the exposure load within the 24-hour HR monitoring proved to be suitable for situations of average HR, under 80 bpm. Conclusion: Individual equations estimate Ve and pollutant load inhaled more accurately, but equations constructed based on a group of individuals can be used to estimate Ve in activities where the HR remains lower
137

Exercício físico e variabilidade da frequência cardíaca em diferentes locais e concentrações de poluição do ar em São Paulo, Brasil / Exercise and heart rate variability in different locations and concentrations of air pollution in São Paulo, Brazil

Paceli, Renato Batista 08 December 2016 (has links)
Introdução: A Poluição do ar é um dos principais fatores de risco de morte no mundo. Estudos têm demonstrado que o exercício regular pode retardar o aparecimento de doenças. Por outro lado, o exercício físico aumenta o volume de ar inalado, resultando em uma maior deposição de poluentes nos pulmões. Objetivos: Avaliar a variabilidade da frequência cardíaca (VFC) durante a realização de exercícios físicos de moderado a intenso, em ambientes com diferentes concentrações de poluentes, em jovens saudáveis que praticam exercícios regularmente. Métodos: 58 indivíduos jovens e saudáveis foram submetidos a avaliação da VFC antes, durante e após a atividade física (7,5 km), em dias diferentes, em um circuito na via pública (CVP) e um circuito em um parque arborizado (CPq). O Polar RS800 foi o equipamento usado para registrar a frequência cardíaca (FC) e VFC, durante 15 minutos em repouso, durante os 45 minutos de corrida e durante os 15 minutos de recuperação. O MP2.5, temperatura (°C) e umidade relativa do ar, em porcentagem, foram monitorados durante as corridas. Resultados: Cinquenta e oito voluntários completaram o protocolo em ambos os circuitos. A idade média dos participantes foi de 19,2 (± 1,1) anos. A concentração média de MP2,5 foi 24,5 (± 12,9) ug/m3 no CPq e 74,8 (± 41,5) ug/m3 no CVP. A FC média observada durante o exercício foi menor no CVP (p = 0,0017). Correr no circuito CVP foi associado com uma maior redução no índice SDNN index em relação ao circuito CPq. Conclusão: A atividade física no CVP foi associada a um efeito adverso na FC e na VFC, acentuando o desequilíbrio autonômico / Introduction: Air pollution is one of major death risks factors on worldwide. Studies have shown that regular exercise can slow down the emergence of diseases. On the other hand, physical exercise increases the volume of air inhaled and, as a result, greater deposition of pollutants in the lungs. Aims: To evaluate the heart rate variability (HRV) during moderate to intense exercise, in environments with different concentrations of pollutants, in healthy young people who practice exercises regularly. Methods: 58 young, healthy individuals underwent HRV assessment before, during, and after physical activity (7.5 km), on different days, which consisted of running a circuit on a public street (PS) and running a circuit in a wooded park (PK). Polar RS800 equipment was used to record the heart rate (HR) and HRV, after 15 minutes at rest, after 45 minutes of running, and after 15 minutes of recovery. MP2.5, temperature (°C), and Percent relative air humidity were monitored during the races. Results: Fifty-eight volunteers completed the protocol in both circuits. Age of participants was 19.2 (± 1.1) years. The average concentration of MP2.5 was 24.5 (± 12.9) ug/m3 in the PK circuit and 74.8 (± 41.5) ug/m3 in the PS circuit. The HR average observed during the exercise was smallest in the PS circuit (p=0.0017). Running in the PS circuit was associated with a greater reduction in the SDNN index regarding PK circuit. Conclusion: Physical activity in PS was associated with an adverse effect in HR and HRV, accentuating the autonomic imbalance
138

Wheeze during the first 18 months of life: a prospective cohort study to explore the associations with indoor nitrogen dioxide, formaldehyde and family history of asthma. / 對室内二氧化氮、甲醛、哮喘家族史和18個月或以下幼童初發性哮喘的關係序列研究 / CUHK electronic theses & dissertations collection / Dui shi nei er yang hua dan, jia quan, xiao chuan jia zu shi he 18 ge yue huo yi xia you tong chu fa xing xiao chuan de guan xi xu lie yan jiu

January 2011 (has links)
Fung, Kit Ching. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 134-144). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / Some appendixes in Chinese.
139

Estimativa  da carga de exposição diária a material particulado em indivíduos expostos a poluição ambiental de origem veicular / Daily exposure load estimate of particulate matter in individuals exposed to environmental vehicular pollution

Izabela Campos Cozza 04 November 2013 (has links)
Introdução: O uso de amostradores individuais de poluentes e a medida da ventilação (Ve) tem sido avaliados para estimar a dose de exposição a poluição. Por ser a Ve uma medida de difícil mensuração em campo, tem-se estimado a Ve a partir da frequência cardíaca (FC) utilizando equações de regressão construídas em teste de esforço cardiopulmonar (TECP). Entretanto, ainda persistem dúvidas quanto à sua aplicabilidade para estimar a Ve em indivíduos com características semelhantes, porem que não realizaram o TECP. O objetivo do estudo foi avaliar modelos para a estimativa da Ve a partir da FC, construído a partir de TECP, e testar sua aplicabilidade com o uso de medidas da FC em campo, em diferentes grupos expostos a poluentes. Métodos: Avaliados 60 homens, não tabagistas, 33 que trabalham em vias públicas (Grupo Via Publica - GVP), 17 que trabalham em um Parque (Grupo Parque - GP) e 10 outros participantes (Grupo teste - GT) para validação dos modelos utilizados. Todos tiveram registros da FC e da concentração de MP2,5, durante 24 horas, e realizaram TECP. Resultados: Foram encontradas grandes variações nas equações de regressão entre os indivíduos, e entre os grupos avaliados, mas o emprego de equações de regressão médias, para estimar a carga de exposição com registro da FC de 24 horas em campo revelou-se adequado para situações de FC média abaixo de 80 bpm. Conclusão: Equações individuais estimam de maneira mais precisa a Ve e a carga inalada de poluentes, mas equações construídas em um grupo de indivíduos podem ser empregadas para estimar a Ve em atividades onde a FC média não é elevada, como ocorre com a maioria das situações habituais de atividades de vida diárias / Background: To evaluate the degree of exposure to air pollutants, ventilation (Ve) measurements and individual pollutant sampler have been used. Given that Ve is difficult to measure in field studies, it has been estimated based on the heart rate (HR) using regression equations that were built with cardiopulmonary exercise test (CPET) results. However, doubt still exists as to its applicability to estimate Ve in groups of individuals who did not perform the CPET. The purpose of this study was to evaluate different models for estimating Ve based on HR, constructed from CPET, and to test the models\' applicability using HR measurements in the field, in different groups exposed to pollutants. Methods: We evaluated 60 men, nonsmokers: 33 public streets workers (Public Street Group - GPS), 17 park workers (Park Group - GP), and 10 other participants (Test Group - GT) for model validation. All subjects underwent HR and PM2.5 concentration recording throughout 24 hours and CPET. Results: We found wide variations in the regression equations between individuals and the assessed groups. Nonetheless, the use of average regression equations to estimate the exposure load within the 24-hour HR monitoring proved to be suitable for situations of average HR, under 80 bpm. Conclusion: Individual equations estimate Ve and pollutant load inhaled more accurately, but equations constructed based on a group of individuals can be used to estimate Ve in activities where the HR remains lower
140

Exercício físico e variabilidade da frequência cardíaca em diferentes locais e concentrações de poluição do ar em São Paulo, Brasil / Exercise and heart rate variability in different locations and concentrations of air pollution in São Paulo, Brazil

Renato Batista Paceli 08 December 2016 (has links)
Introdução: A Poluição do ar é um dos principais fatores de risco de morte no mundo. Estudos têm demonstrado que o exercício regular pode retardar o aparecimento de doenças. Por outro lado, o exercício físico aumenta o volume de ar inalado, resultando em uma maior deposição de poluentes nos pulmões. Objetivos: Avaliar a variabilidade da frequência cardíaca (VFC) durante a realização de exercícios físicos de moderado a intenso, em ambientes com diferentes concentrações de poluentes, em jovens saudáveis que praticam exercícios regularmente. Métodos: 58 indivíduos jovens e saudáveis foram submetidos a avaliação da VFC antes, durante e após a atividade física (7,5 km), em dias diferentes, em um circuito na via pública (CVP) e um circuito em um parque arborizado (CPq). O Polar RS800 foi o equipamento usado para registrar a frequência cardíaca (FC) e VFC, durante 15 minutos em repouso, durante os 45 minutos de corrida e durante os 15 minutos de recuperação. O MP2.5, temperatura (°C) e umidade relativa do ar, em porcentagem, foram monitorados durante as corridas. Resultados: Cinquenta e oito voluntários completaram o protocolo em ambos os circuitos. A idade média dos participantes foi de 19,2 (± 1,1) anos. A concentração média de MP2,5 foi 24,5 (± 12,9) ug/m3 no CPq e 74,8 (± 41,5) ug/m3 no CVP. A FC média observada durante o exercício foi menor no CVP (p = 0,0017). Correr no circuito CVP foi associado com uma maior redução no índice SDNN index em relação ao circuito CPq. Conclusão: A atividade física no CVP foi associada a um efeito adverso na FC e na VFC, acentuando o desequilíbrio autonômico / Introduction: Air pollution is one of major death risks factors on worldwide. Studies have shown that regular exercise can slow down the emergence of diseases. On the other hand, physical exercise increases the volume of air inhaled and, as a result, greater deposition of pollutants in the lungs. Aims: To evaluate the heart rate variability (HRV) during moderate to intense exercise, in environments with different concentrations of pollutants, in healthy young people who practice exercises regularly. Methods: 58 young, healthy individuals underwent HRV assessment before, during, and after physical activity (7.5 km), on different days, which consisted of running a circuit on a public street (PS) and running a circuit in a wooded park (PK). Polar RS800 equipment was used to record the heart rate (HR) and HRV, after 15 minutes at rest, after 45 minutes of running, and after 15 minutes of recovery. MP2.5, temperature (°C), and Percent relative air humidity were monitored during the races. Results: Fifty-eight volunteers completed the protocol in both circuits. Age of participants was 19.2 (± 1.1) years. The average concentration of MP2.5 was 24.5 (± 12.9) ug/m3 in the PK circuit and 74.8 (± 41.5) ug/m3 in the PS circuit. The HR average observed during the exercise was smallest in the PS circuit (p=0.0017). Running in the PS circuit was associated with a greater reduction in the SDNN index regarding PK circuit. Conclusion: Physical activity in PS was associated with an adverse effect in HR and HRV, accentuating the autonomic imbalance

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