110 research outputs found

    The Fetal Brain Sparing Response to Hypoxia: Physiological Mechanisms

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    How the fetus withstands an environment of reduced oxygenation during life in the womb has been a vibrant area of research since this field was introduced by Joseph Barcroft, a century ago. Studies spanning five decades have since used the chronically instrumented fetal sheep preparation to investigate the fetal compensatory responses to hypoxia. This defence is contingent on the fetal cardiovascular system, which in late gestation adopts strategies to decrease oxygen consumption and redistribute the cardiac output away from peripheral vascular beds and towards essential circulations, such as those perfusing the brain. The introduction of simultaneous measurement of blood flow in the fetal carotid and femoral circulations by ultrasonic transducers has permitted investigation of the dynamics of the fetal brain sparing response for the first time. Now we know that major components of fetal brain sparing during acute hypoxia are triggered exclusively by a carotid chemoreflex and that they are modified by endocrine agents and the recently discovered vascular oxidant tone. The latter is determined by the interaction between nitric oxide and reactive oxygen species. The fetal brain sparing response matures as the fetus approaches term, in association with the prepartum increase in fetal plasma cortisol and treatment of the preterm fetus with clinically-relevant doses of synthetic steroids mimics this maturation. Despite intense interest into how the fetal brain sparing response may be affected by adverse intrauterine conditions, this area of research has been comparatively scant but it is likely to take centre stage in the near future.Dino Giussani is supported by the British Heart Foundation, The Biotechnology and Biological Sciences Research Council, The Royal Society, The Wellcome Trust, Action Medical Research and the Isaac Newton Trust. I am grateful to past and present members of my group and Professor Abigail Fowden and Dr Caroline Shaw for insightful discussion.This is the author accepted manuscript. The final version is available from Wiley via http://dx.doi.org/10.1113/JP27109

    Atrial fibrillation and its association with type 2 diabetes and hypertension in a Swedish community.

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    Aim: To explore the prevalence of atrial fibrillation in patients with hypertension and type 2 diabetes and to identify possible mechanisms for the development of atrial fibrillation. Methods: A community-based, cross-sectional observational study was conducted in the primary health care in Skara, Sweden, and 1739 subjects (798 men, 941 women) were surveyed. Patients were categorized as those with hypertension only (n = 597); those with both hypertension and type 2 diabetes (n = 171), and those with type 2 diabetes only (n = 147). In the reference population, 824 normotensive subjects without diabetes were identified and used as controls. Participants were examined for cardiovascular risk factors including fasting blood glucose, serum insulin, blood pressure, lipids and anthropometric measures. Resting electrocardiogram (ECG) was recorded and Minnesota-coded. Insulin resistance was measured by the homeostasis model assessment (HOMA). Results: Age-adjusted prevalence of atrial fibrillation was 2% in patients with hypertension only, 6% in patients with both hypertension and type 2 diabetes, 4% in patients with type 2 diabetes only and 2% in controls, respectively. Age and sex adjusted odds ratios (OR) (95% CI) were; hypertension 0.7 (0.30-1.5), combined hypertension and type 2 diabetes 3.3 (1.6-6.7), and type 2 diabetes 2.0 (0.9-4.7). The association with combined hypertension and type 2 diabetes remained significant when adjusted for cardiovascular disease (CVD) risk factors and body mass index (BMI), was attenuated with adjustment for ischemic ECG; 2.4 (1.1-5.0) and lost significance with adjustment for insulin resistance; 1.3 (0.5-3.1). Conclusions: Atrial fibrillation is associated with the combined occurrence of type 2 diabetes and hypertension. Insulin resistance may be a common underlying mechanism

    The influence of social phobia in first episode of psychosis and attentional processing and the ability to use theory of mind

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    Chapter One: Literature Review This chapter reviews the research surrounding the prevalence of comorbid social phobia in people diagnosed with schizophrenia. It then critically evaluates the eight studies that have specifically explored the relationships, if any, between social phobia and psychotic symptoms. The review surmises that the research findings are inconsistent, which seem to be attributable to methodological differences between all the studies in terms of participant selection, chronicity of psychotic symptoms and lack of consistent measures. Chapter Two: Research Report This study investigates attentional processing, the influence of social phobia and the ability to use Theory of Mind (ToM: the ability to infer other people's mental states and behaviour) in people diagnosed with their first episode of psychosis, when compared to healthy matched controls. The results showed that the first episode group attended towards negative evaluation, somatic sensations, physical threat, but not social situation word groups. Social phobia was highly prevalent in the first episode of psychosis cohort (37%) and this anxiety disorder was unrelated to psychotic symptoms. ToM processing was impaired in the first episode group. ToM was not related to social phobia symptoms, but was related to social functioning. Chapter Three: Critical Appraisal This section presents an overview of the experiences and personal reflections of the work that constitutes this thesis and includes the main personal learning points.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

    Healthy aging and age-adjusted nutrition and physical fitness

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    Expected life span is gradually increasing worldwide. Healthy dietary and exercise habits contribute to healthy ageing. Certain types of diet can prevent or reduce obesity, and may reduce the risk of diseases (e.g. cardiovascular disease). Exercise also reduces the risk of diseases (e.g. cardiovascular disease, osteoporosis, some cancers and some mental disturbances). A less sedentary life style seems at least as important as regular exercise. Exercise can probably be tailored to reduce the risk of cardiovascular disease and extent of bone loss. To ensure adherence, it is important to increase slowly the frequency, duration and intensity of exercise, and to find activities that suit the individual. More research is needed to find ideal modes and doses of exercise, and to increase long-term adherence. Dietary and exercise modification seem to be strong promoters of healthy ageing
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