Systematics and enzymatic activity of Foliar ascomycetes (Fungi) on Lepidozamia peroffskyana and Macrozamia lucida in Eastern Australia

The kingdom Fungi is deeply entangled in the evolutionary history and ecology of life on Earth. The diversity of fungi is poorly known with only 150,000 species described from at least 4 million species by most estimates. The leaf surfaces of plants shelter an extensive diversity of fungi, including filamentous, single-celled, and dimorphic forms. Many extant species may become extinct before their discovery and preservation, due to habitat destruction and a changing climate. Many plants are further under threat in their natural habitats from illegal removal because of their horticultural value. Cycads are one of these horticulturally valuable plants. Cycads are the earliest seed-bearing plants. The fungi found on cycad leaves are often subject to extreme conditions of temperature, humidity, and ultraviolet radiation, which makes them interesting candidates for bioprospecting. This thesis reports the foliar fungi found in association with the leaves of two endemic Australian cycads, Lepidozamia peroffskyana and Macrozamia lucida. Samsoniella sp. and Penicillium sp. were isolated from L. peroffskyana and represent novel species. Periconia cyperacearum was isolated from L. peroffskyana and represents a new host record. A novel species of Acrocalymma and an unidentified fungus were isolated from M. lucida. Several Cladosporium species were isolated from L. peroffskyana and M. lucida. The production of proteases, amylases, cellulases, and mannanases by these fungi was qualitatively investigated using skim milk, starch, cellulose, and galactomannan, as substrates, respectively. Acrocalymma sp. (BRIP 71369a) produced amylase. Cladosporium spp. (BRIP 71372a, BRIP 71364a and BRIP 71173c), and Samsoniella sp. (BRIP 71359b) produced protease and amylase

Stress, ageing and their influence on functional, cellular and molecular aspects of the immune system

The immune response is essential for keeping an organism healthy and for defending it from different types of pathogens. It is a complex system that consists of a large number of components performing different functions. The adequate and controlled interaction between these components is necessary for a robust and strong immune response. There are, however, many factors that interfere with the way the immune response functions. Stress and ageing now consistently appear in the literature as factors that act upon the immune system in the way that is often damaging. This review focuses on the role of stress and ageing in altering the robustness of the immune response first separately, and then simultaneously, discussing the effects that emerge from their interplay. The special focus is on the psychological stress and the impact that it has at different levels, from the whole system to the individual molecules, resulting in consequences for physical health

The Vaccination Model in Psychoneuroimmunology Research: A Review

This chapter explores the reasoning behind using the vaccination model to examine the influence of psychosocial factors on immunity. It then briefly discusses the mechanics of the vaccination response and the protocols used in psychoneuroimmunology vaccine research, before giving examples from the research literature of the studies examining relationships such as the association between stress and vaccination response. It also explores the ways the vaccination model can be used to answer key questions in psychoneuroimmunology, such as the following: “Does it matter when stressful life events occur relative to when the vaccine is received?” “What are the effects of prior exposure to the antigen?” “Do other psychosocial factors influence vaccine response besides stress?” Finally, it briefly considers the mechanisms underlying psychosocial factors and vaccination response associations and the future research needed to understand these better, and indeed to use current and future knowledge to improve and enhance vaccine responses in key at-risk populations

Prospective study of early bereavement on psychological and behavioural cardiac risk factors

Background: Increasing evidence supports the role of emotional stress in the onset of cardiovascular disease. Although bereavement is a major emotional stress with both acute and more long-term features, the mechanism of its association with cardiovascular risk is not well understood, in particular because of limited studies of acute bereavement. The aim of the study was to identify psychological and behavioural changes in acute bereavement and potential modifiers of these changes. Methods: Bereaved (n= 62) and non-bereaved individuals (n= 50) were evaluated within 2 weeks and at 6 months following loss using the Centre for Epidemiologic Studies Depression, Spielberger State Anxiety and Anger, Social Support Questionnaire and changes in appetite, cigarette and alcohol consumption, cortisol and lipids. Results: Compared with non-bereaved, acutely bereaved had increased symptoms of depression (26.7 ± 1.7 vs 5.9 ± 0.7, P < 0.001), anxiety (47.4 ± 2.0 vs 28.2 ± 1.4, P < 0.001) and anger (median 16.0 vs 15.0, P < 0.001). Greater depressive symptoms were associated with being unprepared for the death, decreased sleep duration and younger age. Acutely, bereaved slept less than non-bereaved (5.8 ± 0.2 vs 7.2 ± 0.2 h, P < 0.001). Reduced sleep time was associated with increased anger and depression and decreased satisfaction with social support. Compared with the non-bereaved, the acutely bereaved had higher cortisol (median 306 vs 266, P= 0.003), reduced appetite (P < 0.001) and lower total cholesterol (median 4.9 vs 5.4, P= 0.006) and low-density lipoprotein (median 2.4 vs 2.9, P < 0.001)