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INTRODUCTION: Mitochondrial disorders are a group of metabolic conditions caused by impairment of the oxidative phosphorylation system. The treatment of mitochondrial diseases is still inadequate. Therapies that have been attempted include: respiratory chain cofactors, other metabolites secondarily decreased in mitochondrial disorders, antioxidants, and agents acting on lactic acidosis. However, their role in the treatment of the majority of mitochondrial diseases is still unclear. Furthermore, some drugs may potentially have detrimental effects on mitochondrial dysfunction. AREAS COVERED: To critically review this still unclear field, this paper attempts to answer, on the basis of the basic and clinical literature available to date, the 'frequently asked questions', such as: Is valproic acid safe in mitochondrial patients? What about other antiepileptic drugs? May metformin trigger lactic acidosis in mitochondrial patients? Are statins safe in these subjects? EXPERT OPINION: Randomized clinical trials are necessary to establish efficacy and safety of drugs. Multicenter collaboration is essential for the advancement of therapy for mitochondrial disorders.  相似文献   
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Resting state electroencephalographic (EEG) rhythms do not deteriorate with the increase of white matter vascular lesion in amnesic mild cognitive impairment (MCI) subjects [1], although white matter is impaired along Alzheimer's disease (AD). Here we tested whether this is true even in AD subjects. Closed-eye resting state EEG data were recorded in 40 healthy elderly (Nold), 96 amnesic MCI, and 83 AD subjects. White matter vascular lesions were indexed by magnetic resonance imaging recorded in the MCI and AD subjects (about 42% of cases following ADNI standards). The MCI subjects were divided into two sub-groups based on the median of the white matter lesion, namely MCI+ (people with highest vascular load; n = 48) and MCI- (people with lowest vascular load; n = 48). The same was true for the AD subjects (AD+, n = 42; AD-, n = 41). EEG rhythms of interest were delta (2-4 Hz), theta (4-8 Hz), alpha1 (8-10.5 Hz), alpha2 (10.5-13 Hz), beta1 (13-20 Hz), beta2 (20-30 Hz), and gamma (30-40 Hz). LORETA software estimated cortical EEG sources. When compared to Nold group, MCI and AD groups showed well known abnormalities of delta and alpha sources. Furthermore, amplitude of occipital, temporal, and limbic alpha 1 sources were higher in MCI+ than MCI- group. As a novelty, amplitude of occipital delta sources was lower in AD+ than AD- group. Furthermore, central, parietal, occipital, temporal, and limbic alpha sources were higher in amplitude in AD+ than AD- group. Amplitude of these sources was correlated to global cognitive status (i.e., Mini Mental State Evaluation score). These results suggest that in amnesic MCI and AD subjects, resting state posterior delta and alpha EEG rhythms do not deteriorate with the increase of white-matter vascular lesion. These rhythms might be more sensitive to AD neurodegenerative processes and cognitive status rather than to concomitant lesions to white matter.  相似文献   
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Oxidative stress is a metabolic condition arising from imbalance between the production of potentially reactive oxygen species and the scavenging activities. Mitochondria are the main providers but also the main scavengers of cell oxidative stress. The role of mitochondrial dysfunction and oxidative stress in the pathogenesis of neurodegenerative diseases is well documented. Therefore, therapeutic approaches targeting mitochondrial dysfunction and oxidative damage hold great promise in neurodegenerative diseases. Despite this evidence, human experience with antioxidant neuroprotectants has generally been negative with regards to the clinical progress of disease, with unclear results in biochemical assays. Here we review the antioxidant approaches performed so far in neurodegenerative diseases and the future challenges in modern medicine.  相似文献   
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A common polymorphism (rs3851179) in the PICALM (phosphatidylinositol-binding clathrin assembly protein) gene has been recently associated with reduced risk of developing late-onset Alzheimer’s disease (LOAD). We analyzed the genotype and allele distributions of the PICALM polymorphism in 813 Italian subjects, including LOAD patients and centenarians. The segregation of the PICALM rs3851179 showed no statistically significant difference between LOAD cases and controls. The implication of a genetic variant at PICALM is confirmed for the first time, in centenarians, thus suggesting a possible role in longevity.  相似文献   
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Headache is a frequent symptom of polycythemia. A case study of a polycythemia vera patient affected by migraines, with and without aura, who developed headache attacks with aura in association with elevated haematocrit and haemoglobin levels is presented. A vasculoneural pathogenesis is supposed.  相似文献   
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Opiates and/or nonsteroidal anti-inflammatory drugs (NSAIDs) are among the most effective therapies for chronic pain, but their prolonged time of use can affect health conditions through physical and psychological side effects. They include the very common gastrointestinal effects and changes that can induce osteoporosis, depression, impaired cognition and a generally poor quality of life, which per se can induce and maintain a chronic painful condition. For this reason it is becoming imperative to expand our knowledge of the interaction of these substances with body functions apparently not directly involved in nociception and pain, such as neuroendocrine functions. The purpose of this study was to determine, in male and female patients suffering from chronic pain, the effect of conventional pain therapy (opiates, NSAIDs) on hypothalamic-pituitary-adrenal (HPA) axis function. This was assessed by measuring the blood levels of adrenal-related hormones (adrenocorticotrophin hormone, ACTH; cortisol; dehydroepiandrosterone, DHEA and dehydroepiandrosterone sulfate, DHEAS). The second purpose of the study was to test the hypothesis that these hormones are associated with the psychological profile shown by the chronic pain patients. The results showed significant changes induced by pain therapy on the HPA axis: ACTH, cortisol, DHEA and DHEAS blood levels decreased in all subjects taking opiates or NSAIDs to treat pain. Moreover these changes showed significant correlations with psychological features of the subjects depending on age and sex.  相似文献   
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Pelvic fractures account for 4–5% of all fracturated patients, and they occur in 4–5% of politraumatized patients. In the most of the cases, they are consequent to high-energy trauma with a high percentage of lesions of other organs (cerebral, thoracic, and abdominal lesions. The most of the patients (80%) who die are dying within the first hours after trauma for a massive hemorrhagic shock. When the pelvic fracture and the patient’s hemodynamic conditions are both unstable, osteosynthesis of the fracture is mandatory. Fracture stabilization should be performed within the first hour after trauma (as soon as possible), and it should be considered as part of the resuscitation procedure. We usually make an urgent stabilization of pelvic fracture with an anterior external fixator technique. We have revised all unstable pelvic fractures treated in our department (Orthopaedic Clinic Pisa University) from 2000 up to the 2005 to determine a correct treatment protocol for these lesions. Pelvic stabilization, reducing the pelvic volume and bleeding from the stumps of fracture, determines the arrest of the hemorrhage, as evidenced by the sharp decline in the number of transfusions in postoperative period. In these cases, there is an absolute indication for an urgent pelvic stabilization. Pelvic stabilization, whether temporary or permanent, allows to control the bleeding because it (1) leads to a reduction in the volume pelvis with a containment on the retro-peritoneal hematoma (2) reduces bleeding from the fracture fragments (3) reduces motility fracture promoting the blood clotting. The stabilization of the pelvis also makes it easier to manage the patient and his mobilization for the implementation of subsequent investigations. In our experience, external fixator accounts for its characteristics the gold standard approach for the urgent stabilization of these lesions, and, for most of them, it can be used as the definitive treatment. External fixation is a quick and easy procedure for pelvic fractures stabilization for surgeons with experience with this technique.  相似文献   
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