Avaliação do padrão de metilação de regiões promotoras dos genes ESR1, ESR2 e PGR na endometriose profunda intestinal

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Seasonal aspects of infectious diseases and their causes -USSR,

Mode of access: Internet.

Diet, nutrition and the prevention of chronic diseases : report of a Joint WHO/FAO Expert Consultation

This report examines the science base of the relationship between diet and physical activity patterns and the major nutrition-related chronic diseases. Recommendations are made to help prevent death and disability from major nutrition-related chronic diseases.

The Rpf/DSF system and the regulation of virulence in the plant pathogen Xanthomonas campestris

The full virulence of Xanthomonas campestris pv. campestris (Xcc) to plants depends upon cell-to-cell signalling mediated by the signal molecule DSF (for diffusible signal factor), that has been characterised as cis-11-methyl-2-dodecenoic acid. DSF-mediated signalling regulates motility, biofilm dynamics and the synthesis of particular virulence determinants. The synthesis and perception of the DSF signal molecule involves products of the rpf (regulation of pathogenicity factors) gene cluster. DSF synthesis is fully dependent on RpfF, which encodes a putative enoyl-CoA hydratase. A two-component system, comprising the complex sensor histidine kinase RpfC and the HD-GYP domain regulator RpfG, is implicated in DSF perception. The HD-GYP domain of RpfG is a phosphodiesterase working on cyclic di-GMP; DSF perception is thereby linked to the turnover of this intracellular second messenger. The full range of regulatory influences of the Rpf/DSF system and of cyclic di-GMP in Xcc has yet to be established. In order to further characterise the Rpf/DSF regulatory network in Xcc, a proteomic approach was used to compare protein expression in the wildtype and defined rpf mutants. This work shows that the Rpf/DSF system regulates a range of biological functions that are associated with virulence and biofilm formation but also reveals new functions mediated by DSF regulation. These functions include antibiotic resistance, detoxification and stress tolerance. Mutational analysis showed that several of these regulated protein functions contribute to virulence in Chinese radish. Interestingly, it was demonstrated that different patterns of protein expression are associated with mutations of rpfF, rpfC and rpfG. This suggests that RpfG and RpfC have broader roles in regulation other than perception and transduction of DSF. Taken together, this analysis indicates the broad and complex regulatory role of Rpf/DSF system and identifies a number of new functions under Rpf/DSF control, which were shown to play a role in virulence.

Cardiovascular health behaviours and health needs among people with psychiatric disabilities

Recent research in Australia has found that people with a mental illness experience higher mortality rates from preventable illnesses, such as cardiovascular disease, respiratory disease and diabetes compared to the general population. Lifestyle and other behavioural factors contribute significantly to these illnesses. Lifestyle behaviours that affect these illnesses include lack of physical activity, consumption of a poor diet and cigarette smoking. Research on the influence of these factors has been mainly directed towards the mainstream population in Australia. Consequently, there remains limited understanding of health behaviours among individuals with psychiatric disabilities, their health needs, or factors influencing their participation in protective health behaviours. This thesis presents findings from two studies. Study 1 evaluated the utility of the main components of Roger’s (1983) Protection Motivation Theory (PMT) to explain health behaviours among people with a mental illness. A clinical population of individuals with schizophrenia (N=83), Major Depressive Disorder (MDD) (N=70) and individuals without a mental illness (N=147) participated in the study. Respondents provided information on intentions and self-reported behaviour of engaging in physical activity, following a low-fat diet, and stopping smoking. Study 2 investigated the health care service needs of people with psychiatric disabilities (N=20). Results indicated that the prevalence of overweight, cigarette smoking and a sedentary lifestyle were significantly greater among people with a mental illness compared to that reported for individuals without a mental illness. Major predictors of the lack of intentions to adopt health behaviours among individuals with schizophrenia and MDD were high levels of fear of cardiovascular disease, lack of knowledge of correct dietary principles, lower self-efficacy, a limited social support network and a high level of psychiatric symptoms. In addition, findings demonstrated that psychiatric patients are disproportionately higher users of medical services, but they are under-users of preventive medical care services. These differences are primarily due to a lack of focus on preventive health, feelings of disempowerment and lower satisfaction of patient-doctor relationships. Implications of these results are discussed in terms of designing education and preventive programs for individuals with schizophrenia and MDD.

Effect of dietary arachidonic acid and n-3 polyunsaturated fatty acids on the production of eicosanoids

The major polyunsaturated fatty acid (PUFA) in the western diet is linoleic acid (LA), which is considered to be the major source of tissue arachidonic acid (AA), the principal precursor for the vaso-active eicosanoids via the cyclooxygenase enzymatic pathway. However, dietary AA may contribute significantly to tissue levels of AA in humans, leading to an increase in the production of eicosanoids, particularly the platelet aggregating, vasoconstricting, thromboxane (TXA2), hence increasing thrombosis risk. The aims of this study were to determine the extent to which dietary AA contributed to prostacyclin (PGI2) and TXA2 production in vivo and whether dietary long chain (LC) n-3 PUFA have a modulating influence on the metabolism of AA to these vaso-active eicosanoids. A gas chromatography -mass spectrometry (GCMS) method for urinary PGI2-M determination and a tandem GCMS/MS method for urinary TXA2-M determination were perfected for use within our laboratory (with the assistance of Dr Howard Knapp, University of Iowa and Professor Reinhard Lorenz, Ludwig Maximilian's University, Munich, respectively). An initial animal study compared the in vitro production of PGI2 by aorta segments with the whole body in vivo production of PGI2 in rats fed ethyl arachidonate or the ethyl ester of eicosapentaenoic acid (EPA), at levels many times higher than encountered in human diets. During AA feeding both measures of PGI2 increased, although in vitro TXA2 production was not affected. EPA feeding lowered in vitro TXA2 and in vivo PGI2. Prior to determining the effects of AA and LC n-3 PUFA in humans, a study was carried out to determine the AA and LC n-3 PUFA content of foods and from these, an estimate of the mean daily intake of AA and other LC PUFA. Eggs, organ meats and paté were found to be the richest sources of AA. Of the meat and fish analysed, white meat was found to be relatively rich in AA but poor in LC n-3 PUFA. Lean red meat, particularly kangaroo had similar LC n-3 PUFA and AA content. Fish, although rich in AA, had extremely high levels of LC n-3 PUFA. The calculated mean daily intakes of AA in Australian adults was 130mg (males) and 96mg (females). For total LC n-3 PUFA intake, the mean daily values were 247mg (males) and 197mg (females). Two human pilot studies involving dietary intervention trials examined the effects of dietary AA and AA plus long chain n-3 PUFA on thrombosis risk, gauged by the change in the ratio of PGI2 / TXA2 as well as alterations to other recognised risk factors, such as lipoprotein lipids and platelet aggregation. The desired dietary amounts of AA and LC n-3 PUFA were achieved in the first study by combining food items with known levels of each fatty acid. In the second study, where a diet with approximately equal quantities of AA and LC n-3 PUFA was being examined, kangaroo meat was consumed, following a low-fat vegetarian diet used as a baseline. Diets rich in AA alone (~500mg/day) increased plasma phospholipid (PL) AA levels, PGIi and TXA2 production. When foods containing equal quantities of AA and EPA (∼500mg/day of each) were fed to subjects PGI2 increased, with no change in TXAs production. Low fat vegetarian diets lowered PGI2 production, the level of which was reestablished by an AA rich diet (∼300mg AA/day + ∼260mg/day LC n-3 PUFA) of kangaroo meat. However, TXA2 production was not altered. A final, larger human dietary intervention trial then examined the effects of diets relatively rich in AA alone, AA plus LC n-3 PUFA and LC n-3 PUFA, on the ratio of PGI2/TXA2- The dietary sources of these fatty acids were white meat, red meat and fish, respectively. Each contained a mean level of AA of ∼140mg/day, with varying LC n-3 PUFA levels (59, 161 and 3380mg/day, respectively). Neither meat diet altered PGI2 or TXA2 production significantly, despite increasing serum PL AA levels. The fish diet resulted in a decrease in the serum and platelet PL AA/EPA ratio and TXA2 production, thus increasing the PGI2 / TXA2 ratio. These results would indicate that stores of AA in the body are sufficiently high to have effectively saturated the cyclooxygenase pathway for production of both PGI2 and TXA2, thus making any small change in the plasma level of AA due to 'normal' dietary levels, inconsequential. However, as seen in the rat study and the two pilot studies higher dietary levels of AA can increase both PGI2 and TXA2 production. Increases in platelet levels of EPA and DHA were associated with a decrease in TXA2 production, or the maintenance of a constant TXA2 level, while AA tissue levels and PGI2 production increased. This suggests a possible inhibitory effect of LC n-3 PUFA on the metabolism of AA to TXA2, particularly in platelets. From these short term studies, conducted over 2-3 week periods, it can be concluded that diets rich in lean meats can raise plasma AA levels but do not affect TXA2 or PGI2 production, hence are not pro-thrombotic. Diets rich in long chain n-3 PUFA from fish, raise plasma EPA and DHA levels, lower TXA2 production and are anti-thrombotic. Diets which combine equal quantities of AA and LC n-3 PUFA appear to increase PGI2 production while keeping TXA2 production constant. In order for these LC PUFA to have a significant effect on eicosanoid production the dietary intake of these fatty acids through foods such as red meat or white meat would have to be higher than average current Australian consumption levels.

The relationship between stress and the symptomatology of fibromyalgia

Fibromyalgia is an unexplained but often debilitating syndrome, characterised primarily by widespread pain. This thesis provides direct evidence that physical and emotional stress exacerbates pain, fatigue and other symptoms of Fibromyalgia and supports the assertion that symptoms may be related to disordered stress-response mechanisma in the human brain. The professional portfolio presents four clinical case studies that demonstrate the utility of Acceptance and Commitment Therapy (ACT) in the psychotherapeutic treatment of people with chronic illness.

The impact of violent video-games on cognition, affect and personality

This research investigated the impact of playing violent videogames. Aggressive or anxious responses were most likely: when the player perceived the violence in the games to be extreme, when the player experienced a heightened sense of becoming 'absorbed' into the game, and during a relatively brief exposure to the game. The portfolio explores the use of manualised interventions in psychology research and practice. Four illustrative case studies regarding the efficacy and effectiveness of adapting manualised interventions for clients with chronic health conditions are presented.

Body image in adolescent girls

This study investigated the Tripartite Influence Model of body image and eating disturbance in adolescent females. The model was found to be a satisfactory representation of the social, cultural and individual factors proposed to promote body dissatisfaction, dieting and bulimic behaviours in 14 to 18 year old girls. The portfolio presents four case situations in which the specialist knowledge of a clinical psychologist has shown to be beneficial to pediatric patients, their families, and medical staff at a major metropolitan hospital.

PTSD symptomatology in children and adolescents : treatment development and evaluation

This thesis developed, implemented and evaluated a cognitive-behavioural group treatment programme for children and adolescents experiencing symptoms of PTSD (Post-traumatic stress disorder). Results of the study indicate that symptoms of sleep disturbance and flashbacks, reduced markedly in the participants, providing a useful tool in reducing synptoms experiences by individuals exposed to trauma. The Professional portfolio presents four case studies that demonstrate the clinical application of the affect of chronic illness on the psychological adjustment of the sufferer and their families.

Cellular and molecular components of plant defence against pathogens

This project investigated how plants respond to invading pathogens using microscopic, biochemical and genetic approaches. The development of transgenic plants containing the green fluorescent protein cloned from jellyfish enabled a new approach to studying plant defence genes. In particular, the role and involvement of the plant gene PAL1 was analysed.

Characterisation and comparison of bovine RNA polymerase III promoters for RNA interference

The characterisation of novel bovine RNA polymerase III promoters for the expression of short hairpin RNAs for gene silencing resulted in the identification of a highly efficient promoter sequence. The replication of bovine viral diarrhea virus was them suppressed using short hairpin RNAs expressed form this promoter in vitro.

The neuroanatomical correlates of subjective wellbeing following head injury

The thesis found results supporting the involvement of the Right Frontal area of the brain in the subjective wellbeing (SWB) of individuals. Additional results suggested SWB is dependent upon Core Affect, itself dependent upon the Right Parietal area of the brain. These results provide evidence that SWB and Core Affect are based upon a neurological substrate. The portfolio investigated the association between chronic medical conditions and anxiety disorders, and how the occurence of anxiety issues can affect overall psychological adjustment to illness.

A hypothesised model of disordered eating in overweight women

This thesis found that predicted risk factors for disordered eating were similar for overweight and non-overweight women. However, overweight women reported more stigmatisation and body shame, had a higher risk for developing an eating disorder, and were twice as likely to be diagnosed with a subclinical/clinical eating disorder than non-overweight women. The portfolio presents four case studies demonstrating the considerations and challenges of psychologically assessing and treating individuals with chronic health conditions.