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In the C3(1)/SV40 T-antigen (Tag) FVB/N mouse model of human estrogen and progesterone receptor-negative breast cancer, the stress response elicited by social isolation is associated with increased expression of metabolic genes in...
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In the C3(1)/SV40 T-antigen (Tag) FVB/N mouse model of human estrogen and progesterone receptor-negative breast cancer, the stress response elicited by social isolation is associated with increased expression of metabolic genes in the mammary gland. To further understand accelerated tumor growth associated with social isolation, we separated mammary gland adipocytes from ductal epithelium and stroma and then analyzed individual fractions for changes in metabolic gene expression and function. The increased expression of the key metabolic genes Acaca, Hk2 and Acly was found to be significantly elevated in the adipocytes of the mammary gland, and surprisingly, was not significantly increased in visceral adipose depots of socially isolated female mice. Increased metabolic gene expression in the mammary gland of socially isolated mice coincided with increased glucose metabolism, lipid synthesis, and leptin expression. Furthermore, culture media from isolated versus group-housed mouse mammary adipose tissue resulted in relatively increased proliferation of mammary cancer cells. These results suggest that exposure to chronic social isolation results in metabolic changes in mammary gland adipocytes that contribute to increased growth of adjacent epithelial cell tumors. We propose a model in which environmental stress affects estrogen-independent mammary tumor growth, at least in part, through changes in mammary adipocyte biology.
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Symptoms related to chronic stress and post-traumatic stress were investigated in registered nurses working on intensive care and nonintensive care burn wards and compared to comparable nurses assigned to selected intensive care a...
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Symptoms related to chronic stress and post-traumatic stress were investigated in registered nurses working on intensive care and nonintensive care burn wards and compared to comparable nurses assigned to selected intensive care and nonintensive care wards. Self-report questionnaires assessed job stress, job satisfaction, stressful non-work events, emotional support, coping style, symptoms associated with chronic stress, behaviors associated with post traumatic stress, and demographic data. It was hypothesized: (1) Burn nurses would report more job stress and symptoms and less job satisfaction; (2) there would be a positive correlation between job stress and outside stressors; (3) emotional support would be inversely correlated with job stress; (4) nurses reporting more stress would use fewer coping responses and that the predominant coping style would be emotion-focused; (5) nurses reporting less stress would use more coping responses and that the predominant coping style would be environment-focused. Two analytic designs were used: (l)location of assignment (burn versus nonburn) by category of nursing care (ICU versus NonICU): and (2)location of assignment by level of job stress. Burn nurses were not more stressed or dissatisfied than Nonburn nurses. A significant difference was found on the job related stress scale. Both Nonburn groups reported higher levels of job stress than did both of the burn groups. Nonburn nurses reported significantly more anxiety than did Burn nurses. Burn nurses reported significantly less avoidance behavior than did Nonburn nurses. There were no differences on the job satisfaction scale. There was a significant difference between the high and low stress groups: the high stress group used more emotion-focused responses. A positive correlation was found between job stress and outside stress. An inverse relationship was found between job stress and emotional support.
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Stress management and healthy eating are ongoing struggles for many people in the developed world. The consequences of chronic stress and unhealthy diets are borne at both individual and societal level. Currently, ischemic heart d...
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Stress management and healthy eating are ongoing struggles for many people in the developed world. The consequences of chronic stress and unhealthy diets are borne at both individual and societal level. Currently, ischemic heart disease is the leading cause of death in the world, and depression is the leading cause of disability.Their early prevention calls for scalable and affordable means to provide support for healthy dietary choices and daily recovery from stress. Modern technology offers potential solutions for daily self-management but few health-promoting application shave reached widespread use despite promising research findings.The aims of this thesis were to assess the real-world use of health-promoting online and mobile applications, to evaluate their objective and subjective benefits,and to draw design guidelines for preventive applications. Six studies on online and mobile applications for stress management and healthy eating were conducted with diverse settings and target groups. Two of the studies assessed the use of an online and a mobile application for healthy eating and found that less than 10%of the almost 200,000 users they attracted remained active. Two studies evaluated the benefits of technology tools combined with group intervention for stress management and found improved well-being and active use of tools, although human contact was appreciated most. The last two studies analyzed stress management applications and suggested new design principles for them.Based on the findings, freely available applications can reach a large number of users, but the attrition is likely to be very high and it is unclear whether the intended audience is reached. Applications can contribute to improved well-being and provide support for behavioral changes and skills learning as long as they are simple, attractive and easy to integrate into everyday life. The design of applications should support small daily actions that result in immediate benefits, emphasize self-improvement and reflection, and offer guidance while maintaining freedom of choice. The results support the feasibility and applicability of online and mobile applications for health promotion at individual level and highlight the importance of a systematic theory-driven, user-centric and business-oriented approach to intervention development. The societal impact of the applications may remain small unless real-world implementation, maintenance and dissemination are planned from the very beginning of the development process.
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Chronic stress is associated with increased risk of cardiovascular diseases. Aging is also associated with vascular dysfunction. We hypothesize that chronic stress accelerates collateral dysfunction in old mice. Mice were subjecte...
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Chronic stress is associated with increased risk of cardiovascular diseases. Aging is also associated with vascular dysfunction. We hypothesize that chronic stress accelerates collateral dysfunction in old mice. Mice were subjected to either chronic social defeat (CSD) or chronic cold stress (CCS). The CSD mice were housed in a box inside an aggressor s cage and exposed to the aggressor. The CCS group was placed in iced water. After chronic stress, mice underwent femoral artery ligation (FAL) and flow recovery was measured. For the CSD group, appearance and use scores of the foot and a behavioral test were performed. CSD impaired collateral flow recovery after FAL. Further, stressed mice had greater ischemic damage, impaired foot function, and altered behavior. The CCS mice also showed impaired collateral flow recovery. Chronic stress causes hind limb collateral dysfunction in old mice, a conclusion reinforced by the fact that two types of stress produced similar changes.
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A newly instituted 3 to 4 day/12-hr rotating shift schedule was compared to the previous 5 to 7 day/8-hr schedule using standard laboratory-type measures of performance and alertness, and a questionnaire on sleep patterns and othe...
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A newly instituted 3 to 4 day/12-hr rotating shift schedule was compared to the previous 5 to 7 day/8-hr schedule using standard laboratory-type measures of performance and alertness, and a questionnaire on sleep patterns and other personal habits. After seven months adaptation to the new schedule, a preliminary analysis indicates that there were some decrements in alertness, reductions in sleep, and disruptions of other personal activities during 12-hr workdays. Gastro-intestinal state improved during night shift, however, and increases in self-reported stress were reduced by the shortened workweek. These results are discussed in terms of trade-offs between longer workdays and shorter workweeks. It is emphasized that at this time no determination can be made of the extent of risk associated with these changes in alertness. (ERA citation 12:010009)
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With this project, we propose the development of a novel tool in stress research; a non-invasive method to measure long-term cortisol levels in cetaceans. Cortisol in cetacean skin samples is expected to reflect levels of chronic ...
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With this project, we propose the development of a novel tool in stress research; a non-invasive method to measure long-term cortisol levels in cetaceans. Cortisol in cetacean skin samples is expected to reflect levels of chronic stress, as the acute stress potentially caused by the sampling itself is not expected to enter this matrix for days or even weeks. Skin samples can thus provide information on the long-term physiological status of the animal.
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Our overarching goal is to develop indicators and methods to quantify chronic stress in bottlenose dolphins. Much research has focused on the stimuli which induce stress in marine mammals, as well as the hormonal mediators of the ...
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Our overarching goal is to develop indicators and methods to quantify chronic stress in bottlenose dolphins. Much research has focused on the stimuli which induce stress in marine mammals, as well as the hormonal mediators of the stress response. Stress may be induced by a variety factors, including noise, pollutant or toxin exposure, presence of predators, loss of prey, and/or habitat changes. The stress response is complex and difficult to study experimentally in marine mammals due to ethical and logistical considerations, but has been well characterized in other laboratory mammal species. In mammals as well as other vertebrates, the stress response has two modes of operation: The fast mode involves the rapid release of fast-acting agents, such catecholamines, by the medulla which drive the fight-or-flight response, enhancing vigilance, alertness, arousal, and attention. The catecholamines in turn play a major role in excitation of the hypothalamic- pituitary-adrenal (HPA) axis, initiating a hormonal cascade which culminates in stimulation of the adrenal cortex to secrete glucocorticoids (GCs). The delayed but more sustained response driven by GCs coordinates brain and body functions to cope with stress and facilitate recovery, adaptation, and re-establishment of homeostasis. These functions include mobilization of substrates for energy metabolism, suppression of immune and inflammatory reactions, and inhibition of bone and muscle growth. Studies of both captive and free-ranging individuals support the existence of these same stress response pathways in marine mammals. While the HPA axis and physiological processes driven by the GCs are essential for an individual s ability to respond and adapt to stress, prolonged stimulation can overly burden the body s regulatory systems and induce deleterious effects. Prolonged elevation of GC hormones can lead to chronic immune suppression and inhibition of other energy expending hormonal systems, including reproduction.
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The purpose of this project is to explore the effects of chronic activation of the brain corticotropin releasing factor (CRF) stress system and to investigate individual susceptiblity to this pathological cascade. It is our hypoth...
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The purpose of this project is to explore the effects of chronic activation of the brain corticotropin releasing factor (CRF) stress system and to investigate individual susceptiblity to this pathological cascade. It is our hypothesis that sustained central CRF activation results in damage to the brain dopamine system through oxidative mechanisms and that certain populations may be uniquely susceptible. In Specific Aim I, the goal is to selectively breed rats for high and low response to stressors on the basis of their hypothalamic pituitary adrenal axis response to footshock. Two independent lines (replications) are being bred (the fifth generation of Line 1 is currently in utero and the third generation of Line 2 is nearing weaning). The lines appear to be separating at a steady, although moderate, rate, possibly reflecting a locking in of the original selection. In Specific Aim 2, the goal is to explore the effects of chronic hyperactivity of the brain CRF stress system on dysregulation of brain monoamine systems with a focus on dopamine. Chronic hyperactivity of the CRF system by repeated central administration of CRF produced a temporary dysfunction of the mesocortical and nigrostriatal dopaminergic systems possibly mediated by oxidative damage.
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