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In this paper, several radiomics-based predictive models of response to induction chemotherapy (IC) in sinonasal cancers (SNCs) are built and tested. Models were built as a combination of radiomic features extracted from three types of MRI images: T1-weighted images, T2-weighted images and apparent diffusion coefficient (ADC) maps. Fifty patients (aged 54 ± 12 years, 41 men) were included in this study. Patients were classified according to their response to IC (25 responders and 25 nonresponders). Not all types of images were acquired for all of the patients: 49 had T1-weighted images, 50 had T2-weighted images and 34 had ADC maps. Only in a subset of 33 patients were all three types of image acquired. Eighty-nine radiomic features were extracted from the MRI images. Dimensionality reduction was performed by using principal component analysis (PCA) and by selecting only the three main components. Different algorithms (trees ensemble, K-nearest neighbors, support vector machine, naïve Bayes) were used to classify the patients as either responders or nonresponders. Several radiomic models (either monomodality or multimodality obtained by a combination of T1-weighted, T2-weighted and ADC images) were developed and the performance was assessed through 100 iterations of train and test split. The area under the curve (AUC) of the models ranged from 0.56 to 0.78. Trees ensemble, support vector machine and naïve Bayes performed similarly, but in all cases ADC-based models performed better. Trees ensemble gave the highest AUC (0.78 for the T1-weighted+T2-weighted+ADC model) and was used for further analyses. For trees ensemble, the models based on ADC features performed better than those models that did not use those features (P < 0.02 for one-tail Hanley test, AUC range 0.68–0.78 vs 0.56–0.69) except the T1-weighted+ADC model (AUC 0.71 vs 0.69, nonsignificant differences). The results suggest the relevance of ADC-based radiomics for prediction of response to IC in SNCs.  相似文献   
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Consolidation treatment in acute myeloid leukemia (AML) patients achieving complete remission (CR) is warranted. High-dose cytarabine (HDAC) is considered first choice in favorable risk and an option in intermediate-risk AML. However, its optimal dose and schedule, as well as the benefit of additional chemotherapy agents remain controversial. Herein, we report on the long-term outcome of consecutive unselected AML patients treated with repeated courses of HDAC, with the addition of idarubicin, followed by autologous peripheral blood stem cell (PBSC) support, in order to limit toxicity, according to Northern Italy Leukemia Group (NILG) AML-01/00 study (EUDRACT number 00400673). Among 338 patients consecutively diagnosed from 2001 to 2017 at our center, 148 with high-risk AML (adverse cytogenetic, isolated FLT3-internal tandem duplication mutation, refractory to first induction) were addressed to allogeneic stem cell transplant. All other cases, 186 patients (55%), median age 53 (range 19–75), were considered standard-risk and received the NILG AML-01/00 program. After achieving CR, patients were mobilized with cytarabine 8 g/sqm to collect autologous CD34+-PBSC and received three consolidation cycles with HDAC (20 g/sqm) plus idarubicin (20 mg/sqm) per cycle, followed by reinfusion of limited doses of CD34+ PBSC (1-2x106/kg). The program was completed by 160 (86%) patients. Toxicity was acceptable. Neutrophils recovered a median of 10 days. Treatment-related mortality was 3/160 (1.8%). After a median follow-up of 66.4 months, overall survival (OS) and relapse-free survival (RFS) at 5-years were 61.4% and 52.4%, respectively. Twenty-eight selected patients aged >65 had similar outcomes. According to European leukemia net-2010 classification, the OS and RFS at 5-years were 76.4% and 65% in favorable risk, without differences between molecular subgroups, 52.3% and 47.2% in Intermediate-I, 45.2% and 36.5% in Intermediate-II risk patients, respectively. In conclusion, consolidation including repeated courses of high dose cytarabine and idarubicin, with limited PBSC support, proved feasible and very effective in nonhigh risk patients. The incorporation of novel agents in its backbone may be tested to further improve patient's prognosis.  相似文献   
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The herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) is used on a wide variety of terrestrial and aquatic broadleaf weeds. 2,4-D has been shown to produce a wide range of adverse effects on animal and human health. The aim of the current study was to evaluate the effects of pre- and postnatal exposure to 2,4-D on rat ventral prostate (VP). Pregnant rats were exposed daily to oral doses of 70?mg/kg/day of 2,4-D from 16 days of gestation up to 23 days after delivery. Then, the treated groups (n?=?8) were fed with a 2,4-D added diet until sacrificed by decapitation on postnatal day (PND) 45, 60, or 90. Morphometric studies were performed and androgen receptor (AR) protein levels in the VP were determined. AR, insulin-like growth factor-I (IGF-1) and insulin-like growth factor-I receptor (IGF-1R) mRNA expression in the VP along with testosterone (T), dihydroxytestosterone (DHT), growth hormone (GH) and IGF-1 serum levels were also determined to ascertain whether these parameters were differentially affected. Results of this study showed that 2,4-D exposure during gestation and until adulthood altered development of the prostate gland in male rats, delaying it at early ages while increasing its size in adults, indicate that 2,4-D could behave as endocrine disruptors (EDs).  相似文献   
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The aim of this work was to investigate the effects of chronic treatment with the combination of ezetimibe and simvastatin on gluconeogenesis in rat liver. Rats were treated daily for 28 days with the combination of ezetimibe and simvastatin (10/40 mg/kg) by oral gavage. To measure gluconeogenesis and the associated pathways, isolated perfused rat liver was used. In addition, subcellular fractions, such as microsomes and mitochondria, were used for complementary measures of enzymatic activities. Treatment with the combination of simvastatin and ezetimibe resulted in a decrease in gluconeogenesis from pyruvate (?62%). Basal oxygen consumption of the treated animals was higher (+22%) than that of the control rats, but the resulting oxygen consumption that occurred after pyruvate infusion was 43% lower in animals treated with the combination of simvastatin and ezetimibe. Oxygen consumption in the livers from treated animals was completely inhibited by cyanide (electron transport chain inhibitor), but not by proadifen (cytochrome P450 inhibitor). Chronic treatment with ezetimibe/simvastatin decreased the activity of the key enzymes glucose‐6‐phosphatase and fructose‐1,6‐bisphosphatase by 59% and 45%, respectively, which is probably the major reason for the decreased gluconeogenesis seen in ezetimibe‐/simvastatin‐treated rats. It is also possible that part of the effect of this combination on gluconeogenesis and on the oxygen consumption is related to the impairment of mitochondrial energy transduction.  相似文献   
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Behçet’s syndrome (BS) is a complex disease with different organ involvement. The vascular one is the most intriguing, considering the existence of a specific group of patients suffering from recurrent vascular events involving the venous and, more rarely, the arterial vessels. Several clinical clues suggest the inflammatory nature of thrombosis in BS, especially of the venous involvement, thus BS is considered a model of inflammation-induced thrombosis. Unique among other inflammatory conditions, venous involvement (together with the arterial one) is currently treated with immunosuppressants, rather than with anti-coagulants. Although many in-vitro studies have suggested the different roles of the multiple players involved in clot formation, in-vivo models are crucial to study this process in a physiological context. At present, no clear mechanisms describing the pathophysiology of thrombo-inflammation in BS exist. Recently, we focused our attention on BS patients as a human in-vivo model of inflammation-induced thrombosis to investigate a new mechanism of clot formation. Indeed, fibrinogen displays a critical role not only in inflammatory processes, but also in clot formation, both in the fibrin network and in platelet aggregation. Reactive oxygen species (ROS)-derived modifications represent the main post-translational fibrinogen alterations responsible for structural and functional changes. Recent data have revealed that neutrophils (pivotal in the pathogenetic mechanisms leading to BS damage) promote fibrinogen oxidation and thrombus formation in BS. Altogether, these new findings may help understand the pathogenetic bases of inflammation-induced thrombosis and, more importantly, may suggest potential targets for innovative therapeutic approaches.  相似文献   
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