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排序方式: 共有474条查询结果,搜索用时 218 毫秒
1.
Marco Bocchetti Maria Grazia Ferraro Filippo Ricciardiello Alessandro Ottaiano Amalia Luce Alessia Maria Cossu Marianna Scrima Wing-Yan Leung Marianna Abate Paola Stiuso Michele Caraglia Silvia Zappavigna Tung On Yau 《International journal of molecular sciences》2021,22(8)
Colorectal cancer (CRC) is the third most deadly cancer worldwide, and inflammatory bowel disease (IBD) is one of the critical factors in CRC carcinogenesis. IBD is responsible for an unphysiological and sustained chronic inflammation environment favoring the transformation. MicroRNAs (miRNAs) belong to a class of highly conserved short single-stranded segments (18–25 nucleotides) non-coding RNA and have been extensively discussed in both CRC and IBD. However, the role of miRNAs in the development of colitis-associated CRC (CAC) is less clear. The aim of this review is to summarize the major upregulated (miR-18a, miR-19a, miR-21, miR-31, miR-155 and miR-214) and downregulated (miR-124, miR-193a-3p and miR-139-5p) miRNAs in CAC, and their roles in genes’ expression modulation in chronic colonic-inflammation-induced carcinogenesis, including programmed cell-death pathways. These miRNAs dysregulation could be applied for early CAC diagnosis, to predict therapy efficacy and for precision treatment. 相似文献
2.
Adele Boccuto Filippo Dragoni Francesca Picarazzi Alessia Lai Carla Della Ventura Carla Veo Federica Giammarino Francesco Saladini Gianguglielmo Zehender Maurizio Zazzi Mattia Mori Ilaria Vicenti 《International journal of molecular sciences》2021,22(5)
The nucleotide analog sofosbuvir, licensed for the treatment of hepatitis C, recently revealed activity against the Zika virus (ZIKV) in vitro and in animal models. However, the ZIKV genetic barrier to sofosbuvir has not yet been characterized. In this study, in vitro selection experiments were performed in infected human hepatoma cell lines. Increasing drug pressure significantly delayed viral breakthrough (p = 0.029). A double mutant in the NS5 gene (V360L/V607I) emerged in 3 independent experiments at 40–80 µM sofosbuvir resulting in a 3.9 ± 0.9-fold half- maximal inhibitory concentration (IC50) shift with respect to the wild type (WT) virus. A triple mutant (C269Y/V360L/V607I), detected in one experiment at 80 µM, conferred a 6.8-fold IC50 shift with respect to the WT. Molecular dynamics simulations confirmed that the double mutant V360L/V607I impacts the binding mode of sofosbuvir, supporting its role in sofosbuvir resistance. Due to the distance from the catalytic site and to the lack of reliable structural data, the contribution of C269Y was not investigated in silico. By a combination of sequence analysis, phenotypic susceptibility testing, and molecular modeling, we characterized a double ZIKV NS5 mutant with decreased sofosbuvir susceptibility. These data add important information to the profile of sofosbuvir as a possible lead for anti-ZIKV drug development. 相似文献
3.
Federico Cernuschi Paolo Bison Daniel E. Mack Marco Merlini Stefano Boldrini Stefano Marchionna Stefano Capelli Stefano Concari Alessia Famengo Alessandro Moscatelli Werner Stamm 《Journal of the European Ceramic Society》2018,38(11):3945-3961
In the perspective of fuelling the future generations of gas turbines by hydrogen rich syngas, the evaluation of the effect of a higher water vapour content into the flue gases on the TBC used, or potentially usable, is a need. For this purpose YPSZ APS TBC with two different microstructures have been exposed for 500?h at different temperatures in the range 1000?°C–1250?°C either in air and air +20% vol. H2O. The comparison between the different testing conditions has been performed in terms of sintering kinetics and phase stability, as evaluated by thermal diffusivity measurements and Synchrotron X-Rays diffraction, respectively. Furthermore the characterisation of thermal properties of two innovative TBCs (GZO-YPSZ and YAG) potentially able to withstand the CMAS attack and erosive environments, respectively, has been carried out.No clear evidence of a different behaviour of TBC has been observed, at least in the considered aging time and temperature range. 相似文献
4.
IC Lavery F Lopez-Kostner VW Fazio M Fernandez-Martin JW Milsom JM Church 《Canadian Metallurgical Quarterly》1997,122(4):779-84; discussion 784-5
BACKGROUND: The goal of this study was to compare patterns of recurrence and long-term outcome after sphincter-saving procedures (SSPs) and abdominoperineal resection (APR) in patients with tumors located in the lower third of the rectum. METHODS: We reviewed the charts of 1001 patients operated on for primary rectal adenocarcinoma between 1980 and 1991. All patients with tumors located between 5 and 7 cm from the anal verge and treated with curative intent were included. RESULTS: Of the 261 patients who met our criteria, 162 had undergone SSP and 99 had undergone APR. The local recurrence rates for SSP and APR were 8% and 11%, respectively (p = 0.41), and the distant metastases rates were 23% and 28%, respectively (p = 0.35). Recurrence and distant metastases rates for SSP and APR, respectively, did not differ by TNM classification: state I, 10% versus 9% (p = 0.9); stage II, 25% versus 43% (p = 0.13); and stage III, 56% versus 57% (p = 0.92). Five-year disease-free survival rates for SSP and APR patients were 70.5% and 62.3%, respectively (p = 0.2). CONCLUSIONS: Tumors in the lower third of the rectum can be treated with sphincter-saving procedures without compromising the chance of cure. 相似文献
5.
A computer model was extended and adapted to simulate the hygrothermal behavior of building envelope-wood components. The model was used to predict moisture movement in wood planks forming the decks of nonvented flat roofs insulated with cellulose. The gradient of water potential was considered as the driving force for moisture movement in wood. The model required the determination of convective heat- and mass-transfer coefficients, the sorption curves, the effective water conductivity for different wood species, and the hygrothermal conditions within the assembly to characterize the mass-conservation equation. Once these parameters were integrated in the computer model, this approach was then validated by carrying a simulation of the drying process of wood planks using experimental data from a large-scale test. 相似文献
6.
The aim of this study was to bring to the surface the strategic use of imitative processes in the context of a 2-route model: (a) direct imitation, used in reproducing new, meaningless actions, and (b) imitation based on stored semantic knowledge of familiar meaningful actions. Three experiments were carried out with healthy participants who reproduced meaningful and meaningless actions within an established time limit. The study investigated 3 factors that could potentially affect the selection of processes used for imitation: (a) the composition of the experimental list (blocked or mixed presentation), (b) the presence-absence of instructions (Experiments 1 and 2), and (c) the relative proportions of the stimuli (Experiment 3). Overall, the results suggest that each of these factors influences the selection of imitative strategies in healthy individuals with temporarily reduced capacities, as happens in the case of brain-damaged patients. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
Dr. R. Fazio 《Acta Mechanica》1992,95(1-4):1-7
Summary In the present paper we point out that the correct way to solve the Blasius problem by numerical means is to reformulate it as free boundary value problem. In the new formulation the truncated boundary (instead of infinity) is the unknown free boundary and it has to be determined as part of the numerical solution. Taking into account the partial inavariance of the mathematical model at hand with respect to a stretching group we define a non-iterative transformation method. Further, we compare the improved numerical results, obtained by the method in point, with analytical and numerical ones. Moreover, the numerical results confirm that the question of accuracy depends on the value of the free boundary. Therefore, this indicates that boundary value problems with a boundary condition at infinity should be numerically reformulated as free boundary value problems. 相似文献
8.
Prof. Alessia Carocci Dr. Mariagrazia Roselli Prof. Roberta Budriesi Dr. Matteo Micucci Prof. Jean-François Desaphy Dr. Concetta Altamura Dr. Maria Maddalena Cavalluzzi Dr. Maddalena Toma Dr. Giovanna Ilaria Passeri Dr. Gualtiero Milani Dr. Angelo Lovece Prof. Alessia Catalano Dr. Claudio Bruno Dr. Annalisa De Palma Prof. Filomena Corbo Prof. Carlo Franchini Prof. Solomon Habtemariam Prof. Giovanni Lentini 《ChemMedChem》2021,16(3):578-588
Under the hypothesis that cardioprotective agents might benefit from synergism between antiarrhythmic activity and antioxidant properties, a small series of mexiletine analogues were coupled with the 2,2,5,5-tetramethylpyrroline moiety, known for its antioxidant effect, in order to obtain dual-acting drugs potentially useful in the protection of the heart against post-ischemic reperfusion injury. The pyrroline derivatives reported herein were found to be more potent as antiarrhythmic agents than mexiletine and displayed antioxidant activity. The most interesting tetramethylpyrroline congener, a tert-butyl-substituted analogue, was at least 100 times more active as an antiarrhythmic than mexiletine. 相似文献
9.
Roberta Squecco Alessia Tani Flaminia Chellini Rachele Garella Eglantina Idrizaj Irene Rosa Sandra Zecchi-Orlandini Mirko Manetti Chiara Sassoli 《International journal of molecular sciences》2021,22(7)
Bone marrow-mesenchymal stem/stromal cells (MSCs) may offer promise for skeletal muscle repair/regeneration. Growing evidence suggests that the mechanisms underpinning the beneficial effects of such cells in muscle tissue reside in their ability to secrete bioactive molecules (secretome) with multiple actions. Hence, we examined the effects of MSC secretome as conditioned medium (MSC-CM) on ex vivo murine extensor digitorum longus muscle injured by forced eccentric contraction (EC). By combining morphological (light and confocal laser scanning microscopies) and electrophysiological analyses we demonstrated the capability of MSC-CM to attenuate EC-induced tissue structural damages and sarcolemnic functional properties’ modifications. MSC-CM was effective in protecting myofibers from apoptosis, as suggested by a reduced expression of pro-apoptotic markers, cytochrome c and activated caspase-3, along with an increase in the expression of pro-survival AKT factor. Notably, MSC-CM also reduced the EC-induced tissue redistribution and extension of telocytes/CD34+ stromal cells, distinctive cells proposed to play a “nursing” role for the muscle resident myogenic satellite cells (SCs), regarded as the main players of regeneration. Moreover, it affected SC functionality likely contributing to replenishment of the SC reservoir. This study provides the necessary groundwork for further investigation of the effects of MSC secretome in the setting of skeletal muscle injury and regenerative medicine. 相似文献
10.
Alessia Vignoli Emanuela Risi Amelia McCartney Ilenia Migliaccio Erica Moretti Luca Malorni Claudio Luchinat Laura Biganzoli Leonardo Tenori 《International journal of molecular sciences》2021,22(9)
Precision oncology is an emerging approach in cancer care. It aims at selecting the optimal therapy for the right patient by considering each patient’s unique disease and individual health status. In the last years, it has become evident that breast cancer is an extremely heterogeneous disease, and therefore, patients need to be appropriately stratified to maximize survival and quality of life. Gene-expression tools have already positively assisted clinical decision making by estimating the risk of recurrence and the potential benefit from adjuvant chemotherapy. However, these approaches need refinement to further reduce the proportion of patients potentially exposed to unnecessary chemotherapy. Nuclear magnetic resonance (NMR) metabolomics has demonstrated to be an optimal approach for cancer research and has provided significant results in BC, in particular for prognostic and stratification purposes. In this review, we give an update on the status of NMR-based metabolomic studies for the biochemical characterization and stratification of breast cancer patients using different biospecimens (breast tissue, blood serum/plasma, and urine). 相似文献