Medical hypotheses
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The inflammatory response is an important determinant of outcome after major surgery. Perioperative excessive stimulation of the inflammatory and hemostatic systems plays a role in the development of postoperative ileus, ischemia-reperfusion syndromes (e.g. myocardial infarction), hypercoagulation syndromes (e.g. deep venous thrombosis) and pain; together, these represent a significant fraction of major postoperative disorders. ⋯ Clinical studies have shown that perioperative local anesthetic administration significantly reduces the incidence of thrombosis and postoperative pain, shortens postoperative ileus and decreases hospital stay. On this basis we hypothesize that continuous intravenous administration of local anesthetic perioperatively might prevent or reduce several postoperative disorders resulting from excessive stimulation of inflammatory and hemostatic systems, and thereby improve surgical outcome.
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The classic explanation that women outlive men solely due to hormonal and lifestyle differences, does not withstand a critical analysis. In developed countries, the average gap in life expectancy between the sexes is 7 years. It has widened over the last decades, despite the trend of women copying the 'unhealthy' lifestyle of men. ⋯ Accordingly, the replicative history of male cells might be longer than that of female cells, resulting in the exhaustion of the regeneration potential and the early onset of age-associated diseases predominantly in large-bodied males. Inherited telomere length variation between unrelated individuals might have obscured a clear correlation between body height and mortality, leading to conflicting results in some studies. Finally, I propose that the secular height increase over the last decades, of about 2.5 cm per generation in the western world, has to be blamed for the widening of the gender gap in life expectancy.
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A model previously presented by Uchida in this journal [Med. Hypotheses 53 (1997) 103] described a mechanism for postoperative delirium. It described an increased level of melatonin resulting in a central "serotonin shortage". ⋯ These findings suggest that this initial paradigm requires modification. We propose that both the agitation seen in hyperactive delirium, and the somnolence associated with the hypoactive form could be explained by a disturbance of central tryptophan homeostasis. It is postulated that intervention in the form of melatonin administration may restore tryptophan levels, and prevent delirium.
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The common physiological rationale for migraine, anger, and epileptic attacks is discussed. The potential importance of homeostatic reactions in brain blood perfusion is described. The author speculates that these attacks are induced to meet some urgent biological needs. ⋯ Migraine attack is a subacute local vasomotor response. In contrast, anger and epileptic attacks are different manifestations of acute solemn general neuropsychiatric vasomotor reflexes. The newer paradigm of the etiological integration of these three kinds of attacks based on cerebral hemodynamic change does not only explain the mechanism of seizure-producing treatments such as electroconvulsive therapy, but also indicates the significance of cerebral vasodilative demands for the particular treatment of migraine, aggressive behavior, and epileptic seizures.
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There is growing dissatisfaction regarding the available diagnostic systems for psychiatric disorders (DSM, ICD). Psychiatrists acknowledge that though mental disease reflects brain disorders, the descriptive and symptom based nature of psychiatric diagnosis bears no relation to brain functions. According to Helmut's article published in the October 2003 issue of Science, in the coming decade researchers and psychiatrists will be called upon to propose a basis for the psychiatric diagnostic system of the future. ⋯ Depression and anxiety have been recently linked to alterations of adaptive neuronal plasticity thus reconceptualized as disorders of matching complexity. Finally, psychoses, including schizophrenia spectrum disorders, are reconceptualized as disturbances of neural complexity resulting in altered fast stabilizing plasticity. The new diagnostic system generates testable predictions regarding diagnosis and treatments of mental disorders which may be the future of psychiatry.