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71.
The ankylosed spine is prone to fracture even after minor trauma due to its changed biomechanical properties. The two central features of ankylosing spondylitis (AS) that promote the pathological remodeling of the spine are inflammation and new bone formation. AS is also associated with osteoporosis that is attributed to an uncoupling of the bone formation and bone resorption processes. Therefore, bone resorption occurs and promotes weakening of the spine as well as increased risk of vertebral fractures which can be hugely different in terms of clinical relevance. Even in the presence of symptomatic clinical vertebral fractures, the diagnosis can be overruled by attributing the pain to disease activity. Furthermore, given the highly abnormal structure of the spine, vertebral fracture diagnosis can be difficult on the basis of radiography alone. CT can show the fractures in detail. Magnetic resonance imaging is considered the method of choice for the imaging of spinal cord injuries, and a reasonable option for exclusion of occult fractures undetected by CT. Since it is equally important for radiologists and clinicians to have a common knowledge base rather than a compartmentalized view, the aim of this review article was to provide the required clinical knowledge that radiologists need to know and the relevant radiological semiotics that clinicians require in diagnosing clinically significant injury to the ankylosed spine.  相似文献   
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Several epidemiological, cellular, and molecular studies demonstrate the role of environmental chemicals with endocrine disrupting activities, typical of Westernized societies, in the pathogenesis of numerous diseases including cancer. Nonetheless this information, the design and execution of studies on endocrine disruptors are not yet cognizant that the specific actions of individual hormones often change with development and ageing, they may be different in males and females and may be mediated by different receptors isoforms expressed in different tissues or at different life stages. These statements are particularly true when assessing the hazard of endocrine disruptors against 17β-estradiol (E2) actions in that this hormone is crucial determinant of sex-related differences in anatomical, physiological, and behavioral traits which characterize male and female physiology. Moreover, E2 is also involved in carcinogenesis. The oncogenic effects of E2 have been investigated extensively in breast and ovarian cancers where hormone-receptor modulators are now an integral part of targeted treatment. Little is known about the E2 preventive signalling in colorectal cancer, although this disease is more common in men than women, the difference being more striking amongst pre-menopausal women and age-matched men. This review aims to dissect the role and action mechanisms of E2 in colorectal cancer evaluating the ability of estrogen disruptors (i.e., xenoestrogens) in impair these E2 actions. Data discussed here lead to define the possible role of xenoestrogens in the impairment and/or activation of E2 signals important for colorectal cancer prevention.  相似文献   
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Diet is considered the cornerstone for the prevention of age-related diseases, and a low-fat diet has been considered for decades as the most suitable alternative to achieve this goal. However, mounting evidence supports the efficacy of other alternatives, such as the Mediterranean diet. Nevertheless, it is well known that people present a dramatic range of responses to similar environmental challenges, and it has been shown that some of this variability is rooted in the genome. In fact, this knowledge is driving the field of nutrigenetics. The finding of interactions between diet and genetic variants has led to intense research and debate about the effectiveness of personalized nutrition as a more suitable tool for the prevention of chronic diseases than the traditional 1-size-fits-all recommendations. Here, we provide some of our own examples that illustrate the progression of nutrigenetics through the years, from the initial studies within the Framingham Heart Study, to the most recent use of large consortia, such as the Cohorts for Heart and Aging Research in Genomic Epidemiology, and ending up with large dietary intervention studies, such as the PREDIMED (Prevención con Dieta Mediterránea) study. These recent approaches are providing more robust and clinically relevant gene–diet interactions. Therefore, although the current evidence level of applying genomic information to tailoring is at its early stages, the prospect of widespread incorporation of nutrigenetics to the clinical practice is encouraging.  相似文献   
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Our aim was to investigate and determine the associations between oxidative stress (OS), dyslipidemia and inflammation in patients treated with continuous ambulatory peritoneal dialysis (CAPD) and hemodialysis (HD) using observational cross‐sectional study. Twenty patients in CAPD and 48 in HD for at least 8 weeks and aged ≥18 years were included in the study. Individuals with malignant or acute inflammatory disease were excluded. A control group of 17 healthy individuals was also recruited. The biochemical parameter evaluations were analyzed using colorimetric kits for albumin, serum glucose, total cholesterol (TC) and lipid fractions. To determine the inflammatory status, CRP, IL‐6 and TNF‐α were analyzed by automated chemiluminescence kits. Plasma advanced oxidation protein products (AOPP) were determined by spectrophotometry. Mean AOPP levels were significantly higher for the HD group compared to the control, and there was no difference in AOPP concentrations between the control and CAPD groups. Dialysis patients had levels of inflammatory parameters higher than controls, and showed a high prevalence of patients with dyslipidemia, especially in CAPD. In the HD group, AOPP was positively correlated with triglycerides (TG) and inversely associated with HDL. Also the HD group was observed to have negative associations between TNF‐α and HDL, LDL and TC. In the CAPD group, CRP was inversely correlated with HDL. Hemodialysis patients had increased protein OS and associations of inflammation and dyslipidemia were also observed in these dialysis groups. A more detailed characterization of the relations between oxidative stress and other more traditional risk factors has therapeutic importance, since cardiovascular diseases are the leading cause of death among dialysis patients.  相似文献   
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Even‐number, medium‐chain dicarboxylic acids (DAs), naturally occurring in higher plants, are a promising alternative energy substrate. Unlike the homologous fatty acids, DAs are soluble in water as salts. They are β‐oxidized, providing acetyl‐CoA and succinyl‐CoA, the latter being an intermediate of the tricarboxylic acid cycle. Sebacic acid and dodecanedioic acid, DAs with 10 and 12 carbon atoms respectively, provide 6.6 and 7.2 kcal g−1 each; therefore, their energy density is intermediate between glucose and fatty acids. Dicarboxylic acids have been proved to be safe in both experimental animals and humans, and their use has recently been proposed in diabetes. Studies in animals and humans with type 2 diabetes showed that oral administration of sebacic acid improved glycaemic control, probably by enhancing insulin sensitivity, and reduced hepatic gluconeogenesis and glucose output. Moreover, dodecanedioic acid intake reduced muscle fatigue during exercise in subjects with type 2 diabetes, suggesting an improvement of energy utilization and ‘metabolic flexibility’. In this article, we review the natural sources of DAs, their fate in animals and humans and their effect in improving glucose metabolism in type 2 diabetes.  相似文献   
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