Thesis (MSc)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: The uropygial gland of most birds produces a variety of hydrocarbons, lipids, waxes, fatty acids, alcohols and other organic compounds. These compounds have two widely recognized functions, viz. they are considered essential for the maintenance of a good plumage condition, and may be used for fungicidal, bactericidal or other hygienic purposes. Scimitar-billed woodhoopoes, Rhinopomastus cyanomelas, are groupterritorial birds that live in groups comprising between two and twelve individuals. Individuals enter the roost cavities shortly after sunset and exit the following morning soon after sunrise. During the period that the birds are inside the roost, they are vulnerable to a range of vertebrate predators, including snakes, genets and rats. When disturbed while roosting, woodhoopoes immediately face away from the threat hence presenting their uropygial glands in the direction of the threat. Typically, a drop of brown, highly pungent secretion is then formed at the tip of the papilla to the uropygial gland, and kept in place by a few tuft-like feathers. This response pattern has led some observers to believe that the secretion serves an anti-predatory role. It has been found that the synthetic volatile constituents of the uropygial secretion of the green woodhoopoe, P. purpureus, individually or as a mixture, have potent defensive properties against feline and reptilian predators. In addition, the compounds also showed activity against a range of bacteria. The aim of the present study was to determine the chemical composition of the uropygial secretion of the scimitar-billed woodhoopoe, Rhinopomastus cyanomelas, as a first step towards the evaluation of, inter alia, the semiochemical function of the secretion. Using gas chromatography-mass spectrometry, 179 constituents of the uropygial secretion of the scimitar-billed woodhoopoe have been identified. The majority of the constituents of the secretion are branched and unbranched aldehydes (aliphatic and aromatic), acids (aliphatic and aromatic), sulfides and ketones. This group of volatile compounds is responsible for the obnoxious odour of the secretion and possibly also for its defensive action against predators. The secretion also contains a large number of branched and unbranched alkanes and wax esters. The chemical composition of the secretion was compared with the secretion of P. purpureus as well as with that of the hoopoe, Upupa africana. The uropygial gland secretion of the scimitar-billed woodhoopoe is quite similar to that of the green woodhoopoe, although it is much more complex than that of the green woodhoopoe. In contrast to the uropygial secretions of the green and the scimitar-billed woodhoopoes, the secretion of Upupa africana does not have a strongly obnoxious odour and it also does not contain large quantities of alkanes and wax esters. / AFRIKAANSE OPSOMMING: Die uropigiale klier van die meeste voëls produseer 'n verskeidenheid van koolwaterstowwe, lipiede, was-esters, vetsure, alkohole en ander organiese verbindings. Hierdie verbindings het twee algemeen erkende funksies, naamlik die instandhouding van die goeie kondisie van die vere, en 'n swam- en kiemdodende werking. Swartbekkakelaars (Engels: scimitar-billed woodhoopoes ), Rhinopomastus cyanomelas, is groep-territoriale voëls wat in groepe van tussen twee en twaalf saam woon. Individue gaan hul neste net na sononder binne en verlaat dit weer die volgende oggend net na sonsopkoms. Terwyl die voëls binne die neste is, is hulle kwesbaar ten opsigte van aanval deur verskeie gewerwelde roofdiere, insluitende slange, muskeljaatkatte en rotte. Wanneer hulle in hul neste gesteur word, sal kakelaars onmiddellik wegdraai van die bedreiging sodat die uropigiale klier in die rigting van die bedreiging gekeer is. 'n Druppel bruin, uiters onwelriekende afskeiding vorm dan by die punt van die papil na die uropigiale klier, en word in posisie gehou deur 'n verekwassie. Hierdie gedragspatroon het aanleiding gegee tot die gedagte by sommige waarnemers dat die afskeiding as afweerstof teen roofdiere dien. Daar is gevind dat die sintetiese vlugtige komponente van die uropigiale afskeiding van die groenkakelaar, P. purpureus, individueel of as 'n mengsel, sterk afweer-eienskappe teen katte en reptiele toon. Daarbenewens het die verbindings ook aktiwiteit getoon teen 'n reeks van bakterieë. Die doel van die huidige studie was om die chemiese samestelling van die uropigiale afskeiding van die swartbekkakelaar, Rhinopomastus cyanomelas, te bepaal as 'n eerste stap met die oog op die evaluering van, onder andere, die semiochemiese funksie van die afskeiding. Deur van gaschromatografie-massaspektrometrie gebruik te maak, is 179 komponente van die uropigiale afskeiding van die swartbekkakelaar geïdentifiseer. Die meeste van die komponente is vertakte en onvertakte aldehiede (alifaties en aromaties), sure (alifaties en aromaties), sulfiede en ketone. Hierdie groep vlugtige verbindings is verantwoordelik vir die afstootlike reuk van die afskeiding en waarskynlik ook vir sy afweer-aksie teen roofdiere. Die afskeiding bevat ook 'n groot aantal vertakte en onvertakte alkane en wasesters. Die chemiese samestelling van die afskeiding is vergelyk met die van P. purpureus sowel as dié van die hoepoe, Upupa africana. Die uropigiale klierafskeiding van die swartbekkakelaar stem tot 'n groot mate ooreen met dié van die groenkakelaar, alhoewel dit veel meer kompleks is as dié van die groenkakelaar. In teenstelling met die uropigiale afskeidings van die groen- en die swartbekkakelaars, het die afskeiding van Upupa africana nie 'n afstootlike reuk nie en bevat dit ook nie groot hoeveelhede alkane en was-esters nie.

published_or_final_version / Community Medicine / Master / Master of Public Health

published_or_final_version / Community Medicine / Master / Master of Philosophy

Objectives: In recent decades, obesity reached epidemic proportions in western countries, while cigarette smoking decreased. Traditionally, smoking is associated with lower relative weight (body mass index, BMI) but high abdominal obesity (waist-hip ratio, WHR). However, several recent studies suggest that BMI is higher among today’s smokers compared with non-smokers. Therefore, the present study examined whether the relationship between smoking and each of the body measures, BMI and WHR, has changed over time. Material and Methods: Data were collected from 5907 male and female residents of Gothenburg, Sweden, aged 25-65 years, and drawn randomly in four sequential cross-sections (1985, 1990, 1995, 2002) from the city’s population register. The study used general linear models to test trends over time, and adjusted all differences for age. Results: The data reported here showed higher WHR in both male and female smokers compared with non-smokers. BMI was lower in female smokers compared with female non-smokers, but did not differ significantly between male smokers and male non-smokers. Among female participants, differences in WHR between smokers and non-smokers increased significantly throughout the study. Although male participants showed a similar tendency, the differences were not significant. Adjustment for educational level did not affect the results. Conclusions: WHR was higher among smokers compared with non-smokers; this difference increased over time. Thus, concern for obesity does not provide a valid reason to continue smoking; on the contrary, it may be a reason to quit. / <p>ISBN 978-91-86739-06-5</p>

The primary objective of the work presented in this thesis was to identify trends in maternal body mass index (BMI) over time, the demographic predictors of those women most at risk of being obese in pregnancy, health inequalities, and the impact of maternal obesity on maternity services. A mixed methodology utilised quantitative and qualitative research to address these objectives. Data were collated from 34 maternity units across England, including 619,323 deliveries between 1989 and 2007 inclusive. Analysis identified an increasing incidence of maternal obesity over time, regional differences in incidence, and significant inequalities with women residing in the highest levels of deprivation, and Black ethnic group. A systematic review was carried out including 49 studies investigating obesity and pregnancy outcomes with acute maternity resource implications. The meta-analysis found significantly increased odds of a number of outcomes, and concluded that maternal obesity had a considerable impact on maternity resources, and contributed towards a poorer prognosis for the mother and the baby during delivery and in the immediate post-partum period. Qualitative interviews and focus groups with 30 HCPs across eight NHS Trusts in the North East of England were carried out to identify barriers in implementing maternal obesity services, and to gain HCPs perspectives on what they felt was required in order to address maternal obesity effectively. The study identified the themes of ‘Service Development’, ‘Psychosocial Issues and Maternal Obesity Services’, ‘Information, Evidence, and Training’, and ‘Where to go From Here?’. Overall this programme of research has identified that maternal obesity is increasing over time and is significantly associated with health inequalities. The increase in maternal obesity has an impact on acute services, and HCPs feel that a holistic approach is required through partnership work in order to address maternal obesity effectively. This programme of research has primarily contributed to the knowledge of maternal obesity with the provision of the first national level statistics for trends in maternal obesity. The research has also provided a holistic view of the impact of obesity in pregnancy on maternity services, including the impact on resources and the issues relating to addressing the maternal obesity in clinical practice. The research has also identified aspects of service that need to be improved, and knowledge gaps in how to move services forward to effective address maternal obesity. The contribution of this research to the knowledge base is emphasised in the journal pre-publications, dissemination through UK and European, and international conference presentations, being an invited speaker at a number of conferences in the UK, and I received the 2007 Association for the Study of Obesity (ASO) Student Researcher Award for producing exemplary work in the study of obesity.

The aims of the present study were to investigate the association between overweight and cognitive ability and dementia, and to evaluate the usefulness of self-reported body mass index (BMI) in late life and various data sources commonly used in epidemiological studies to identify persons with dementia. Data were drawn from three population-based studies: the Swedish Adoption/Twin Study of Aging (SATSA), Aging in Women and Men: A Longitudinal Study of Gender Differences in Health Behaviour and Health among Elderly (the Gender Study), and the Finnish Lieto Study. In Study I, the agreement between self-reported and measured BMI over time was evaluated among 774 men and women, ages 40 to 88 years at baseline (mean age 63.9) participating in both the questionnaire phase and in-person testing of SATSA. Latent growth curve (LGC) modeling showed a small but significant increase between self-reported and measured BMI (0.02 kg/m2/y) over time, which would probably not affect the results if self-reported BMI were used as a continuous variable in longitudinal research. In Study II, the agreement between dementia diagnoses from various sources and dementia diagnoses set at a consensus conference was evaluated. Among the 498 elderly people ages 70 to 81 at baseline (mean age 74.5) enrolled in the Gender Study, 87 were diagnosed with dementia during an eight-year period. Review of medical records and nurse evaluations yielded the highest sensitivity (0.83 and 0.80, respectively) and a high specificity (0.98 and 0.96), indicating that these sources might be good proxies of dementia, while data extraction from the Swedish Inpatient Discharge Registry underestimated the prevalence of dementia (sensitivity 0.26). In Study III, the association between being overweight in midlife and cognitive ability in late life was examined in SATSA. The 781 participants ages 25 to 63 at baseline (mean age 41.6) in 1963 or 1973 self-reported their height and weight. From 1986 until 2002, they were assessed five times using a cognitive test battery. LGC models showed that people with higher midlife BMI scores had significantly lower cognitive ability and a significantly steeper decline than their thinner counterparts, an association that persisted when those who developed dementia during the study period were excluded from the analysis. This finding indicates that being overweight might affect cognitive ability independently of dementia. In Study IV, the association between BMI and dementia risk in older persons was described among 605 persons without dementia and ages 65 to 92 at baseline (mean age 70.8) in the Lieto Study. Among these, 86 persons were diagnosed with dementia during eight years of follow-up. Cox regression analyses indicated that for each unit increase in BMI score, the risk of dementia decreased 8% (hazard ratio = 0.92, 95% confidence interval = 0.87–0.97) and the association remained significant when individuals who developed dementia during the first four years of follow-up were excluded from the analyses. This result suggests that low BMI scores are present almost a decade before clinical dementia onset.

ABSTRACT The Implications of Chronic Stress on Obesity: Allostatic Load on Body Mass Index (BMI) Classification in the United States, NHANES 2005-2006 INTRODUCTION: In this modern environment, our world is reflecting an exponential increase in not only population, but in body size. Obesity is an overwhelming public health concern among the United States population. Research has shown there is a positive correlation between adiposity and stress. Allostatic load (AL) has been presented to be a consistent measure of chronic stress damage on the body. Yet, there is few studies exemplifying the presence AL on classification of body mass index (BMI). AIM: The aim of this study is to find a relationship between allostatic load (AL) and body mass index (BMI) classification in the United States adult population on a large national scale. This complex interaction can predetermine who among the US population will be at greater risk for excess adiposity following this psychoneuroendocrinology. METHODS: A representative sample size of n=3826 was gathered using NHANES data (2005-2006). Criteria for sample included all United States adults that had numerical values for 10 biomarkers chosen to represent chronic stress damage (allostatic load) along with individual body mass index (BMI). Allostatic load (low, high) and BMI classification (underweight to class III obese) were further categorized on severity and computed in SPSS to find significance between gradients of each variable (α=.05). Cross-sectional analysis and logistical regression (multivariate) were used to further decipher an association between allostatic load and BMI category. RESULTS: A strong positive correlation between allostatic load risk and BMI category was found (p<.001). Also among the variables in the study, significance was found within the strata of age, gender, race, smoking status and poverty income ratio (PIR). Findings show a strong statistically significant relationship between allostatic load and BMI. DISCUSSION: It is imperative to decipher the directional relationship between stress and obesity to provide effective treatment. Understanding the pathology of how stress affects adiposity could open the door for many clinical and public health interventions to eradicate a very preventable outcome. By addressing the effect of chronic stress, a new avenue of prevention can be developed to combat the growing obesity rates in the United States.

The population of the United States is increasingly gaining weight each year.Americans are heavier than they have ever been. African American women are at the forefront of this pandemic. This study addresses the higher prevalence of overweight and obesity among African American women in comparison to White women. Behavioral, psychological, and social known contributors to overweight and obesity using the National Health Interview Survey, 2001 dataset were examined in this study. The research concluded that even when controlling for vigorous exercise, education, income, depression, emotional support, smoking, health coverage, and age, race is the most important predictor of body mass index. Consistent with previous studies, strong race effects still remained.

Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Bc. Barbora Šmídová Supervisor: Prof. MUDr. Jaroslav Dršata, CSc. Supervisor - specialist: RNDr. Mgr. Alena Tichá, PhD. Title of diploma thesis: CHANGES OF LIPID SPECTRUM DURING BODY MASS REDUCTION IN PATIENTS WITH DIABETES MELLITUS The thesis deals with the determination of lipid parameters (plasma total fatty acids, plasma total cholesterol, lipoprotein cholesterol, plasma triglycerides, plasma cholesterol precursors (lathosterol and squalene) and markers of cholesterol absorption (β-sitosterol and campesterol)) in obese patiens with diabetes mellitus type 1 and type 2 who were tested with a seven-day fasting, followed by low-calorie diabetic diet. It is assumed that weight loss should improve insulin resistence. The aim of this work is to evaluate the lipid parameters during the body weight reduction in obese patients suffering with diabetes mellitus. Lipids were determined before and after a seven-day fasting and after one month from the beginning of fasting (in patiens with diabetes mellitus type 1 also after one year). Gas chromatography was used for the determination of fatty acids and non-cholesterol sterols and squalene. Cholesterol and triglycerides were determined by a routine...

Introdução No Brasil a obesidade é um importante problema de saúde pública com prevalência mais elevada em mulheres do que em homens. A gestação e o período pós-parto são momentos críticos devido à ocorrência de ganho ponderal excessivo na gravidez e retenção de peso pós-parto. Objetivos Estudar a influência da paridade sobre o IMC em mulheres brasileiras com idade entre 20 e 49 anos .Investigar o possível efeito de modificação do poder aquisitivo,escolaridade e utilização do SUS sobre a associação entre paridade e IMC. Métodos Foram analisados dados da Pesquisa Nacional de Demografia e Saúde 2006, inquérito que utilizou amostragem complexa representativa de todo o território brasileiro. A associação entre o fator de estudo (paridade: 0,1,2, 3 e + ) e o desfecho (IMC) foi testada mediante análise de regressão linear. O efeito ajustado do fator de estudo sobre o IMC foi avaliado em modelo múltiplo contendo como variáveis de controle: idade, classes de poder aquisitivo ABEP (A+B1, B2+C+D e E), e escolaridade (<8 e 8 anos de estudo completo). Para testar as interações de interesse foram realizados modelos múltiplos, em separado,incluindo três variáveis que combinam paridade dicotômica (nulíparas e demais) com poder aquisitivo,escolaridade e utilização do SUS.Foram considerados significativos valores de p inferiores a 0,05. Resultados Das 13.087 mulheres investigadas foram excluídas do estudo 14,4 % (gestantes, mulheres com filhos menores de 6 meses e aquelas com dados incompletos para peso e altura). A análise foi conduzida em uma amostra de 11.961 mulheres, levando-se em consideração a estrutura complexa da amostra. A média de IMC para o conjunto das mulheres brasileiras foi de 25,6 Kg/m2 (IC95%: 25,4 - 25,8). O IMC médio foi maior entre as pertencentes à classe de poder aquisitivo intermediária (B2,C,D) e baixa (E). Observou-se elevação do IMC com o aumento do número de filhos e idade. Na análise ajustada,confirmou-se a associação positiva entre paridade e IMC (p de tendência < 0,001). Dentre as interações testadas foi estatisticamente significativa a existente entre poder aquisitivo,paridade e IMC. As mulheres com um filho ou mais pertencentes à classe intermediária de poder aquisitivo quando comparadas às nulíparas da classe alta, apresentaram um incremento de 1,40 unidades de IMC (IC95% : 0,64 2,19 p < 0,001 ). Nas demais classes (A+B1) e (E) não foi detectada associação estatisticamente significativa entre paridade e IMC.Conclusões Nas mulheres brasileiras,a paridade exerce influência positiva sobre o IMC após controle de variáveis de confundimento. Detectou-se interação entre poder aquisitivo, paridade e IMC: o efeito da paridade é estatisticamente significativo apenas nas mulheres da classe intermediária de poder aquisitivo (B2,C eD). / Introduction - In Brazil, obesity is a public health problem and its prevalence is higher among women. Pregnancy and the postpartum period are critical moments for the occurrence of excessive weight gain and weight retention. Objectives - To study the influence of parity on BMI in Brazilian women aged between 20 and 49 years. To investigate the possible modifying effect of the purchasing power, schooling and the use of public health system in the relation between parity and BMI. Methods - We used data from the National Demographic and Health Survey 2006, a survey with a complex sample, nationally representative of the Brazilian territory. The association between the study factor (parity: 0,1,2, and 3 +) and the outcome (BMI) was tested by linear regression analysis. The effect of parity on BMI was evaluated by a multivariate model adjusted by control variables: age, score ABEP (A + B1, B2 + C + D and E) and education (<8 and 8 years of study). To test the interactions, multivariate models were performed in separate with three different variables combining parity (nulliparous and others) with purchasing power, education and use of the public health system. The level of significance adopted was p < 0,05. Results - From the 13.087 women screened, 14,4% were excluded (pregnant women, women with children under 6 months and those with incomplete data for height and weight). The analysis was conducted on a sample of 11.961 women, adjusted by the complex structure. The mean BMI of the Brazilian women was 25,6 kg/m2 (95% CI: 25,4 to 25,8). It was higher among women in the middle class purchasing power (B2, C, D) and in the lower class (E). The BMI was elevated with the increase of parity and age. In adjusted analysis, the positive association of parity on BMI was confirmed (p trend <0,001). There was a statistically significant interaction among purchasing power, parity and BMI. When compared to nulliparous upper class women, those with one or more children in the middle class had an increase of 1,40 BMI units (95% CI: 0,64 to 2,19 p <0,001). Among the other purchasing classes (A + B1) and (E) there wasnt significant association between parity and BMI. Conclusion In the Brazilian women, parity influences positively the mean BMI, after adjustment for confounding variables. An interaction was detected among purchasing power, parity and BMI: the effect of parity is statistically significant only in women from the middle class (B2, C and D).