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Several hundreds of studies recently investigated mean platelet volume (MPV) as measured by electronic cell counters in a wide variety of acquired diseases, and most of them found that platelet size was significantly increased with respect to healthy subjects. On this basis, it has been suggested that MPV can be used for diagnostic purposes. Moreover, investigation of subjects with arterial thrombosis not only revealed that their platelets were larger than those of controls, but also found that a high MPV predicted poor prognosis. Despite the large amount of available data, the pathogenesis of increased platelet size in these conditions is unclear. In particular, we do not know whether the increased platelet size is the cause or the consequence of thrombosis. Differences in MPV between patients and controls are usually very small and they reach the statistical significance because of the large number of investigated patients and the standardized methodology for MPV measurement. In real life, the wide variability of MPV possibly due to platelet count, sex, age, and ethnicity, as well as the very poor standardization of the methodologies used for MPV measurement, makes it impossible to decide whether an individual patient has normal or instead slightly increased MPV. So, MPV has presently no role in making diagnosis and defining prognosis in any acquired illness.  相似文献   
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To evaluate outcome in patients treated with stereotactic body radiotherapy (SBRT) on bone oligometastases from castration-sensitive prostate cancer after primary treatment. We retrospectively collected data of patients with less than five lesions at time of SBRT and hormone-naïve disease at the first extra-regional localization, treated between 03/2012 and 11/2016. Prostate-specific antigen (PSA) was measured every 3 months after SBRT. Imaging was performed in case of progression. Survival analysis was performed with Kaplan–Meier (log-rank test) approach. Fifty-five patients were treated on 77 bone oligometastases. Median age, initial PSA and pre-SBRT PSA were 72 years, 9.12 and 3.5 ng/mL, respectively. Twenty-five patients (45%) received SBRT alone while the remaining 30 patients (55%) received concomitant ADT. Median follow-up was 24.6 months (range 3.0–67.2 months). No acute or late toxicity of grade?>?1 was reported. Clinical progression was observed in 38 (69%) patients. 1-year biochemical progression-free survival (b-PFS), clinical progression-free survival (c-PFS), prostate-specific survival (PCSS) and local control (LC) rates were 51, 56, 100 and 83%, respectively. Comparing patients treated with SBRT alone and with concomitant ADT, no significant differences were found for those outcomes. SBRT is safe and allows high 1-year LC rate (83%) with low toxicity profile. No significant improvement in outcomes was registered with the addition of ADT to SBRT.  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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Group A Streptococcus (GAS) is a human pathogen causing a wide range of mild to severe and life-threatening diseases. The GAS M1 protein is a major virulence factor promoting GAS invasiveness and resistance to host innate immune clearance. M1 displays an irregular coiled-coil structure, including the B-repeats that bind fibrinogen. Previously, we found that B-repeat stabilisation generates an idealised version of M1 (M1*) characterised by decreased fibrinogen binding in vitro. To extend these findings based on a soluble truncated version of M1, we now studied the importance of the B-repeat coiled-coil irregularities in full length M1 and M1* expressed in live GAS and tested whether the modulation of M1–fibrinogen interactions would open up novel therapeutic approaches. We found that altering either the M1 structure on the GAS cell surface or removing its target host protein fibrinogen blunted GAS virulence. GAS expressing M1* showed an impaired ability to adhere to and to invade human endothelial cells, was more readily killed by whole blood or neutrophils and most importantly was less virulent in a murine necrotising fasciitis model. M1-mediated virulence of wild-type GAS was strictly dependent on the presence and concentration of fibrinogen complementing our finding that M1–fibrinogen interactions are crucial for GAS virulence. Consistently blocking M1–fibrinogen interactions by fragment D reduced GAS virulence in vitro and in vivo. This supports our conclusion that M1–fibrinogen interactions are crucial for GAS virulence and that interference may open up novel complementary treatment options for GAS infections caused by the leading invasive GAS strain M1.  相似文献   
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Aging is associated with impaired scavenging of reactive oxygen species (ROS). Here, we show that TAp73, a p53 family member, protects against aging by regulating mitochondrial activity and preventing ROS accumulation. TAp73-null mice show more pronounced aging with increased oxidative damage and senescence. TAp73 deletion reduces cellular ATP levels, oxygen consumption, and mitochondrial complex IV activity, with increased ROS production and oxidative stress sensitivity. We show that the mitochondrial complex IV subunit cytochrome C oxidase subunit 4 (Cox4i1) is a direct TAp73 target and that Cox4i1 knockdown phenocopies the cellular senescence of TAp73-null cells. Results indicate that TAp73 affects mitochondrial respiration and ROS homeostasis, thus regulating aging.  相似文献   
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