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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
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4.
Broggi A. Cellario M. Lombardi P. Porta M. 《Industrial Electronics, IEEE Transactions on》2003,50(1):18-29
This paper presents an evolutionary approach able to process a digital image and detect tracks left by preceding vehicles on ice and snow in Antarctica. Biologically inspired by a colony of ants able to interact and cooperate to determine the shortest path to the food, this approach is based on autonomous agents moving along the image pixels and iteratively improving an initial coarse solution. The unfriendly Antarctic environment makes this image analysis problem extremely challenging, since light reflections, abruptly varying brightness conditions, and different terrain slopes must be considered as well. The ant-based approach is compared to a more traditional Hough-based solution and the results are discussed. 相似文献
5.
Effect of Particle Size on Monometallic and Bimetallic (Au,Pd)/C
on the Liquid Phase Oxidation of Glycerol 总被引:2,自引:0,他引:2
Nikolaos Dimitratos Jose Antonio Lopez-Sanchez David Lennon Francesca Porta Laura Prati Alberto Villa 《Catalysis Letters》2006,108(3-4):147-153
The influence of metal particle size of monometallic and bimetallic supported catalysts (Au, Pd, Au–Pd)/C was studied using
as a model reaction the liquid phase oxidation of glycerol. By tuning the metal particle size from 2 to 16 nm a progressive
decrease of activity and simultaneously an increase in the selectivity to sodium glycerate was observed. Moreover, the influence
of the temperature was studied and it was found that by increasing the temperature, only with a large particle size the formed
glycerate was retained and not over-oxidized to tartronate. 相似文献
6.
The effect of solute impregnation on water loss and oil uptake during potato strip frying was studied. Blanched potato strips were impregnated at 25°C by soaking in a solution of sucrose-NaCl-water, 20-5-75% by weight. After rinsing and air drying, strips were deep fried in sunflower oil at 160, 170 and 180°C. A control treatment, consisting of potato strips blanched but not soaked and later air dried was also conducted. Solute impregnation provided a decrease of the oil uptake. Two models, based on Fick's law were used to describe water loss during frying. The first one is the classic model with an effective moisture diffusion coefficient assumed a constant value. The second model considers that diffusion coefficient varies during the frying process. For a given frying temperature, constant diffusion coefficient for control potatoes resulted in lower values than the impregnated ones. The variable diffusivity model showed a two-stage behavior: during the first stage of frying, diffusion coefficient increased with frying temperatures, but from a given time on an inverse behavior began. This last fact was found to be related to an increase of the measured peak force needed to penetrate the potato crust. 相似文献
7.
GS Wengler A Lanfranchi T Frusca R Verardi A Neva D Brugnoni S Giliani M Fiorini P Mella F Guandalini E Mazzolari S Pecorelli LD Notarangelo F Porta AG Ugazio 《Canadian Metallurgical Quarterly》1996,348(9040):1484-1487
BACKGROUND: X-linked severe combined immunodeficiency (SCIDXI) is an inherited immune defect which leads to death in infancy from severe infections. The defect is caused by mutations of the IL-2RG gene that encodes for the common gamma chain shared by several cytokine receptors. The disease is characterised by lack of T and NK cells with normal numbers of B cells. SCIDXI can be cured by bone marrow transplantation (BMT) or prevented by abortion after prenatal diagnosis. METHODS: A male fetus was diagnosed as having SCIDXI by molecular, immunophenotypic, and functional analyses. The fetus was injected intraperitoneally under ultrasound guidance with CD34 haematopoietic progenitor cells purified from paternal bone marrow and T-cell depleted by E rosetting. Chimerism analysis was by HLA-DQ alpha typing and gamma-chain staining on cord blood. FINDINGS: A healthy 3.6 kg boy was delivered by caesarean section at 38 weeks of gestation with no clinical or laboratory signs of graft-versus-host disease. Engraftment of donor-derived CD2 cells was found at birth. At 3.5 months of age the infant is well and his T-cell counts and function are normal. INTERPRETATION: In-utero transplantation of haematopoietic progenitor cells allowed immune reconstitution of a fetus with SCIDXI and may be an alternative to elective abortion. Our report should encourage applications of this method to other inherited disorders curable by BMT. 相似文献
8.
G Porta I Zucchi L Hillier P Green V Nowotny M D'Urso D Schlessinger 《Canadian Metallurgical Quarterly》1993,16(2):417-425
The contents of Alu- and L1-containing TaqI restriction fragments were assessed by Southern blot analyses across YAC contigs already assembled by other means and localized within Xq24-q28. Fingerprinting patterns of YACs in contigs were concordant, and using software based on that of M. V. Olson et al. (1986, Proc. Natl. Acad. Sci. USA 83: 7826) to analyze digitized data on fragment sizes, fingerprinting itself could establish matches among about 40% of a test group of 435 YACs. At 100-kb resolution, both repetitive elements were found throughout the region, with no apparent enrichment of Alu or L1 in DNA of G compared to that found in R bands. However, consistent with a random overall distribution, delimited regions of up to 100 kb contained clusters of repetitive elements. The local concentrations may help to account for the reported differential hybridization of Alu and L1 probes to segments of metaphase chromosomes. 相似文献
9.
G Bianchi D Barone E Lanzarotti R Tettamanti R Porta D Moltrasio A Cedro L Salvetti M Mantovani G Prino 《Canadian Metallurgical Quarterly》1993,238(2-3):327-334
The binding of single-stranded polydeoxyribonucleotides to adenosine A1 and A2 receptors was investigated. Defibrotide, a natural substance with established anti-thrombotic and anti-ischaemic effects, displaced [3H]CHA (N6-cyclohexyl-adenosine) and [3H]NECA (5'-N-ethylcarboxamido-adenosine) concentration dependently, completely and competitively. Ki values of 371 +/- 68 and 688 +/- 115 micrograms/ml (mean +/- S.E.M. of 4-5 replications) were computed for adenosine A1 and A2 sites, respectively. Higher and lower molecular weight polydeoxyribonucleotides displayed comparable affinity, whereas a double-stranded polydeoxyribonucleotide and a polyanion with a negative charge comparable to that of defibrotide were inactive. Defibrotide did not affect the total number of binding sites in radioligand saturation experiments. Defibrotide relaxed the K(+)-contracted guinea-pig trachealis muscle (IC50 = 4001 micrograms/ml) about one-third as potently as the CHA-contracted preparation and as potently as the resting preparation. NECA, a mixed adenosine A1/A2 receptor agonist, behaved similarly. The effects were abolished by the adenosine A1/A2 receptor blocker 8-phenyltheophylline, but not by the selective A1 blocker, 1,3-dipropyl-8-(2-amino-4-chlorophenyl)-xanthine. These results demonstrate that defibrotide binds to adenosine receptors and triggers pharmacological responses comparable to those of a known agonist. 相似文献
10.
Laura Prati Alberto Villa Francesca Porta Di Wang Dangsheng Su 《Catalysis Today》2007,122(3-4):386-390
The liquid phase oxidation of glycerol with oxygen has been studied using mono and bimetallic catalysts based on Au and Pd metals supported on activated carbon, in order to study the effect of the metal on the distribution of the products and on activity of catalysts. It was found that by using bimetallic catalysts (Au–Pd) a strong synergistic effect was shown. By using a preformed nucleating centre we were able to obtain a single alloyed phase, which allowed us to address the synergistic effect to the presence of alloyed Au/Pd. The advantage of using this latter catalyst lies not only in the high activity but also in a prolonged catalyst life. Although a partial leaching of palladium and assembling of the particles have been revealed by ICP and HRTEM respectively, activity after 10 re-cycles decreased less than expected (about 10%). 相似文献