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Cancer cells undergo genetic changes allowing their adaptation to environmental changes, thereby obtaining an advantage during the long metastatic route, disseminated of several changes in the surrounding environment. In particular, plasticity in cell motility, mainly due to epigenetic regulation of cancer cells by environmental insults, engage adaptive strategies aimed essentially to survive in hostile milieu, thereby escaping adverse sites. This review is focused on tumor microenvironment as a collection of structural and cellular elements promoting plasticity and adaptive programs. We analyze the role of extracellular matrix stiffness, hypoxia, nutrient deprivation, acidity, as well as different cell populations of tumor microenvironment.  相似文献   
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ObjectiveThe purpose of the present research was to compare the residual microbial load in Solo System microfiber mops with silver and in normal microfiber mops without silver to see whether those with the silver prevent bacterial proliferation and spread more effectively during normal cleaning operations.MethodsMops with and without silver were experimentally contaminated with suspension of Staphylococcus aureus ATCC 6538. The bioburden was evaluated by a filtering procedure according to UNI EN 1174 after contamination, after washing and after different times of impregnation in an alcohol-base detergent.Results and discussionThe results obtained lead to the conclusion that silver microfiber mop was significantly more effective in reducing bacterial load despite initial high level contamination (106-107 CFU/50 cm2). Indeed, after low temperature washing, the bacterial load was already completely eliminated while the mop without silver still presented relatively high levels of the microorganism (approximately 102 CFU/50 cm2) even after being soaked for 8 hours in a detergent/disinfectant.  相似文献   
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Background  

Thromboelastography is a technique that surveys the properties of viscoelastic blood clot. The purpose of this paper was to evaluate the hypercoagulability state and the effect of antithrombotic prophylaxis on thromboelastogram (TEG) results in bariatric surgery.  相似文献   
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AIMS: Treatment delay is a powerful predictor of survival in ST-elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (PCI). We investigated effectiveness of pre-hospital diagnosis of STEMI with direct referral to PCI, alongside more conventional referral strategies. METHODS AND RESULTS: From January 2003 to December 2004, 658 STEMI patients were referred for primary PCI at our intervention laboratory. Three predefined referral routes were compared: (1) for patients within 90 min drive of the PCI centre, pre-hospital diagnosis and direct transportation (n=166), (2) diagnosis at the interventional hospital emergency department (n=316), (3) diagnosis at local hospitals before transportation (n = 176). Pre-hospital diagnosis was associated with more than 45 min reduction in treatment delay (P = 0.001). No significant difference in in-hospital mortality was apparent in the overall study population. In the cardiogenic shock subgroup (n = 80), pre-hospital diagnosis was associated with a two-thirds reduction in in-hospital mortality (P = 0.019); mortality was only 6.2% in shock patients who underwent PCI in < 2 h. CONCLUSION: This study shows that pre-hospital diagnosis can provide a reduction in primary PCI treatment delay, and suggests the hypothesis that this referral strategy might provide survival benefits to patients with cardiogenic shock.  相似文献   
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Previous studies have documented the involvement of the central nervous system serotonin in promoting wakefulness. There are few and conflicting results over whether there is an actual association between bearing the short allele of serotonin transporter promoter polymorphism (5‐HTTLPR) and worse sleep quality. This study examined whether sleep onset latency complaint is associated with the 5‐HTTLPR triallelic polymorphism in the SLC6A4 gene promoter and whether this polymorphism influences the relationship between sleep onset latency complaint and depressive symptoms in elderly people. A total of 1321 community‐dwelling individuals aged 70–74 years were interviewed for sleep onset latency complaint and for sleep medication consumption. Participants’ genomic DNA was typed for 5‐HTTLPR and rs25531 polymorphisms. Depressive symptoms were evaluated with the Geriatric Depression Scale Short form and general medical comorbidity was assessed by the Cumulative Illness Rating Scale. The presence of a past history of depression was recorded. The S′ allele of the 5‐HTTLPR triallelic polymorphism was associated with sleep onset latency complaint. This association was maintained after adjusting for depressive symptoms, sex, age, history of depression and medical comorbidity. After stratification for 5‐HTTLPR/rs25531, only in S′S′ individuals high depressive symptoms were actually associated with sleep onset latency complaint. These data indicate that the low‐expressing 5‐HTTLPR triallelic polymorphism is an independent risk factor for sleep onset latency disturbance. Furthermore, the 5‐HTTLPR genotype influences the association between depressive symptoms and sleep onset latency complaint.  相似文献   
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Introduction: Amyotrophic Lateral Sclerosis (ALS) is a progressive, incurable neurodegenerative disease that targets motoneurons. Cell-based therapies have generated widespread interest as a potential therapeutic approach but no conclusive results have yet been reported either from pre-clinical or clinical studies.

Areas covered: This is an integrated review of pre-clinical and clinical studies focused on the development of cell-based therapies for ALS. We analyze the biology of stem cell treatments and results obtained from pre-clinical models of ALS and examine the methods and the results obtained to date from clinical trials. We discuss scientific, clinical, and ethical issues and propose some directions for future studies.

Expert opinion: While data from individual studies are encouraging, stem-cell-based therapies do not yet represent a satisfactory, reliable clinical option. The field will critically benefit from the introduction of well-designed, randomized and reproducible, powered clinical trials. Comparative studies addressing key issues such as the nature, properties, and number of donor cells, the delivery mode and the selection of proper patient populations that may benefit the most from cell-based therapies are now of the essence. Multidisciplinary networks of experts should be established to empower effective translation of research into the clinic.  相似文献   

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