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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In recent years, the perception has grown that conflicts of interest are having a detrimental effect on medical science as it influences health policy and clinical practice, leading medical journals to enforce self-declaration of potential biases in the attempt to counteract or compensate for the problem. Conflict of interest (CoI) declarations have traditionally been considered inappropriate in pure science since its evaluation systems themselves constitute a mechanism for eliminating the effect of individual biases. Pure science is primarily evaluated by 'peer usage', in which scientific information is 'replicated' by being incorporated in the work of other scientists, and tested by further observation of the natural world. ⋯ But since peer review does not adequately filter-out conflicts of interest in applied medical science, there is a need for the evolution of specialist post-publication institutional mechanisms. The suggested solution is to encourage the establishment of independent 'CoI consultancy' services, whose role would be to evaluate conflicts of interest and other biases in published applied medical science prior to their implementation. Such services would be paid-for by the groups who intend to implement applied medical research.
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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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Bone metastasis are a frequent complication of cancer, occurring in up to 70% of patients with advanced breast or prostate cancer. The consequences of bone metastasis are often devastating. Osteolytic metastasis can cause different kinds of skeletal related events including severe pain, pathologic fractures, life-threatening hypercalcemia, spinal cord compression, and other nerve-compression syndromes. ⋯ Local calcium also promotes tumor growth and the production of parathyroid hormone-related peptide which in turn stimulates bone resorption. Vitamin D and calcium supplementation during bisphosphonate administration for the purpose of elimination of the side effects related to hypocalcemia in patients with bone metastasis may increase the bone resorption and decrease the efficacy of bisphosphonates. Therefore, vitamin D and calcium supplementation must not be routinely recommended during bisphosphonate administration.
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Clinical Trial Controlled Clinical Trial
Is pigment epithelium-derived factor level in cerebrospinal fluid a promising biomarker for early diagnosis of Alzheimer's disease?
Alzheimer's disease (AD) is the most common cause of dementia in Western countries and in Japan. Early diagnosis and treatment is needed to slow down the degenerative process and dementia in AD. The main histopathological characteristics of AD are senile plaques and neurofibrillary tangles. ⋯ These results suggest that PEDF overexpression may indicate a compensation mechanism to fight against neuronal cell injury in AD. Our present observations suggest that PEDF in CSF might reflect cerebral PEDF turnover and provide a means for monitoring neuronal perturbation induced by oxidative stress in the early stage of AD. Clinical use of CSF-PEDF as a biomarker for AD might enable more effective diagnosis and treatment of patients with this disorder.