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排序方式: 共有1462条查询结果,搜索用时 15 毫秒
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Roberto Zefferino Claudia Piccoli Sante Di Gioia Nazzareno Capitanio Massimo Conese 《International journal of molecular sciences》2021,22(5)
Connexin- and pannexin (Panx)-formed hemichannels (HCs) and gap junctions (GJs) operate an interaction with the extracellular matrix and GJ intercellular communication (GJIC), and on account of this they are involved in cancer onset and progression towards invasiveness and metastatization. When we deal with cancer, it is not correct to omit the immune system, as well as neglecting its role in resisting or succumbing to formation and progression of incipient neoplasia until the formation of micrometastasis, nevertheless what really occurs in the tumor microenvironment (TME), which are the main players and which are the tumor or body allies, is still unclear. The goal of this article is to discuss how the pivotal players act, which can enhance or contrast cancer progression during two important process: “Activating Invasion and Metastasis” and the “Avoiding Immune Destruction”, with a particular emphasis on the interplay among GJIC, Panx-HCs, and the purinergic system in the TME without disregarding the inflammasome and cytokines thereof derived. In particular, the complex and contrasting roles of Panx1/P2X7R signalosome in tumor facilitation and/or inhibition is discussed in regard to the early/late phases of the carcinogenesis. Finally, considering this complex interplay in the TME between cancer cells, stromal cells, immune cells, and focusing on their means of communication, we should be capable of revealing harmful messages that help the cancer growth and transform them in body allies, thus designing novel therapeutic strategies to fight cancer in a personalized manner. 相似文献
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Chitosan (CHT) is a non-toxic and inexpensive compound obtained by deacetylation of chitin, the main component of the exoskeleton of arthropods as well as of the cell walls of many fungi. In agriculture CHT is used to control numerous diseases on various horticultural commodities but, although different mechanisms have been proposed, the exact mode of action of CHT is still unknown. In sycamore (Acer pseudoplatanus L.) cultured cells, CHT induces a set of defense/stress responses that includes production of H2O2 and nitric oxide (NO). We investigated the possible signaling role of these reactive molecules in some CHT-induced responses by means of inhibitors of production and/or scavengers. The results show that both reactive nitrogen and oxygen species are not only a mere symptom of stress conditions but are involved in the responses induced by CHT in sycamore cells. In particular, NO appears to be involved in a cell death form induced by CHT that shows apoptotic features like DNA fragmentation, increase in caspase-3-like activity and release of cytochrome c from the mitochondrion. On the contrary, reactive oxygen species (ROS) appear involved in a cell death form induced by CHT that does not show these apoptotic features but presents increase in lipid peroxidation. 相似文献
4.
Michele Carenini Angus Whyte Lorenzo Bertorello Massimo Vanocchi 《Intelligent Systems, IEEE》2007,22(1):20-27
E-democracy, the design and development of new techniques for improving communication between public administration and citizens, is a major application field for natural language processing and language engineering. Helping citizens access information in a friendly, intuitive way is the primary objective of a global e-democracy framework. The E-democracy European Network project (EDEN) aimed at discovering whether a particular NLP (natural language processing) approach could further e-democracy by increasing citizens' participation in the decision-making process. The goal was twofold: to test whether e-democracy requirements could be meet using advanced linguistic technology and to test whether augmented phrase structure grammars (APSGs) were robust and well-assessed enough to use in a real-world environment. Also, the aim is to develop two toolsets to improve communication between PAs and citizens in the context of urban planning: a set of NLP-based tools to simplify access to information and knowledge and a set of forum and polling devices 相似文献
5.
INTRODUCTION: Cystic fibrosis is a recessive genetic systemic exocrinopathy caused by a variety of mutations in the cystic fibrosis transmembrane conductance regulator gene (CFTR). The disease is characterized by alterations of the secretions, which become thickened and viscous. Both the paranasal sinuses and the lung parenchyma are involved in all cases. The aim of this study was to assess a correlation between the rhinosinusal and lung parenchyma changes in cystic fibrosis patients. MATERIAL AND METHODS: Eighteen patients (11 men and 7 women, age range: 8 to 22 years) were examined with chest HRCT and sinonasal low dose CT. Lung symptoms were found in all patients; 13 of them, also affected with rhinosinusal symptoms, had been examined with ENT and nasal endoscopy. The other 5 patients, without rhinosinusal symptoms and previously examined with ENT, were evaluated as control group. Chest CT was performed with the high-resolution technique, 2 mm slice thickness and 10 mm table feed. Rhinosinusal CT was performed with the low dose technique, acquiring contiguous 2-4 mm thickness coronal sections. The CT patterns were analyzed by two radiologists and scored as slight, medium and diffuse involvement of both districts. RESULTS: No statistically significant correlation between lung and sinonasal damage was found in our study. Parenchymal lung involvement appeared more severe than sinonasal involvement in 14/18 patients. The retention of secretions in the paranasal sinuses, even if limited, was demonstrated in all symptomatic and asymptomatic patients. CONCLUSIONS: The absence of correlation between pulmonary and sinonasal damage and more generally, the different severity of cystic fibrosis can be caused by different allele mutations of the cystic fibrosis transmembrane conductance regulator gene, the most frequent of which is Delta F-508. 相似文献
6.
MG Tozzi-Ciancarelli C Di Massimo G Ascani A Corbacelli 《Canadian Metallurgical Quarterly》1998,18(2-3):151-156
A number of retinal proteins are phosphorylated by a variety of kinases, resulting in well-known regulatory effects. The identity and role of corresponding phosphatases is less clear. We simultaneously measured the activity of serine/ threonine protein phosphatases type 1, 2A and 2C in bovine retinae. The enzymes were classified according to substrate specificity, divalent cation requirement and the effect of phosphatase subtype-specific inhibitors. The total- and specific activity of phosphatase type 2A was prevalent. Type 2C was 10-fold less abundant. 80% of type 1 and 50% of type 2A and type 2C, respectively, were soluble. An economic purification scheme was developed. We demonstrated the presence of phosphatase isozymes 2Calpha and 2Cbeta in bovine rod outer segments by enzymatic analysis as well as immunological techniques. The results suggest a yet unknown role of phosphatase type 2C in phototransduction. On the other hand, the immense amount of protein phosphatases found to be soluble - therefore not associated with rod outer segment membranes - points towards participation of these enzymes in the process of visual transduction not considered thus far. 相似文献
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Christine Di Massimo Paul A. Lant Aidan Saunders Gary A. Montague Ming T. Tham A. Julian Morris 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1992,53(3):265-277
The last decade has seen the development of a number of approaches for estimating those variables which are difficult to measure on-line in industrial process situations. Whilst a range of techniques is available, a common element is the use of process knowledge in the form of a system model. In the case of bioprocess systems, although a large range of models has been presented in the literature, their use in estimation schemes on an industrial scale has been limited. A number of reasons can be identified for their low level of utilisation. Of particular significance is the uncertainty which exists in quantifying system performance and the process-model mismatch which inevitably results. The level of ‘pre-defined model’ uncertainty, together with the knowledge gained during the course of the fermentation, serves to dictate estimator structure. The paper considers a range of estimation strategies and contrasts, through industrial applications, their performance characteristics and utility. 相似文献
9.
Gennaro?Della?Vecchia Luigi?GalloEmail author Massimo?Esposito Antonio?Coronato 《Multimedia Tools and Applications》2012,59(1):341-362
In healthcare facilities most of the daily activities require strict coordination between clinicians, who often operate under
heavy workloads and minimal workforce conditions in environments filled with increasingly complex technology. Ubiquitous Computing
applications constitute a suitable solution for both reducing medical costs and improving patient safety by better supporting
clinical processes. In this study we introduce an intelligent infrastructure for smart hospitals which implements basic services
to optimize medical staff/patient interactions and grants ubiquitous and transparent access to clinical data stored in standard
clinical databases. This infrastructure relies on the integration of Radio Frequency IDentification (RFID) and photosensor
technologies to identify, locate and track clinicians and patients equipped with mobile devices and wearable RFID tags. 相似文献
10.