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排序方式: 共有1475条查询结果,搜索用时 62 毫秒
911.
Razvan Bucuresteanu Monica Ionita Viorel Chihaia Anton Ficai Roxana-Doina Trusca Cornelia-Ioana Ilie Andrei Kuncser Alina-Maria Holban Grigore Mihaescu Gabriela Petcu Adela Nicolaev Ruxandra M. Costescu Mihai Husch Viorica Parvulescu Lia-Mara Ditu 《International journal of molecular sciences》2022,23(13)
The ability of TiO2 to generate reactive oxygen species under UV radiation makes it an efficient candidate in antimicrobial studies. In this context, the preparation of TiO2 microparticles coated with Ca- and Cu-based composite layers over which Cu(II), Cu(I), and Cu(0) species were identified is presented here. The obtained materials were characterized by a wide range of analytical methods, such as X-ray diffraction, electron microscopy (TEM, SEM), X-ray photoelectron (XPS), and UV-VIS spectroscopy. The antimicrobial efficiency was evaluated using qualitative and quantitative standard methods and standard clinical microbial strains. A significant aspect of this composite is that the antimicrobial properties were evidenced both in the presence and absence of the light, as result of competition between photo and electrical effects. However, the antibacterial effect was similar in darkness and light for all samples. Because no photocatalytic properties were found in the absence of copper, the results sustain the antibacterial effect of the electric field (generated by the electrostatic potential of the composite layer) both under the dark and in light conditions. In this way, the composite layers supported on the TiO2 microparticles’ surface can offer continuous antibacterial protection and do not require the presence of a permanent light source for activation. However, the antimicrobial effect in the dark is more significant and is considered to be the result of the electric field effect generated on the composite layer. 相似文献
912.
Rosa Della Monica Mariella Cuomo Michela Buonaiuto Davide Costabile Raduan Ahmed Franca Marialaura Del Basso De Caro Giuseppe Catapano Lorenzo Chiariotti Roberta Visconti 《International journal of molecular sciences》2022,23(13)
Epigenetic changes in DNA methylation contribute to the development of many diseases, including cancer. In glioblastoma multiforme, the most prevalent primary brain cancer and an incurable tumor with a median survival time of 15 months, a single epigenetic modification, the methylation of the O6-Methylguanine-DNA Methyltransferase (MGMT) gene, is a valid biomarker for predicting response to therapy with alkylating agents and also, independently, prognosis. More recently, the progress from single gene to whole-genome analysis of DNA methylation has allowed a better subclassification of glioblastomas. Here, we review the clinically relevant information that can be obtained by studying MGMT gene and whole-genome DNA methylation changes in glioblastomas, also highlighting benefits, including those of liquid biopsy, and pitfalls of the different detection methods. Finally, we discuss how changes in DNA methylation, especially in glioblastomas bearing mutations in the Isocitrate Dehydrogenase (IDH) 1 and 2 genes, can be exploited as targets for tailoring therapy. 相似文献
913.
Gianfranco Fontana Natale Badalamenti Maurizio Bruno Davide Castiglione Monica Notarbartolo Paola Poma Alberto Spinella Marco Tutone Manuela Labbozzetta 《International journal of molecular sciences》2022,23(12)
Oleanolic acid (OA) and Lupeol (LU) belong to the class of natural triterpenes and are endowed with a wide range of biological activities, including cytotoxicity toward several cancer cell lines. In this context, we investigated a set of compounds obtained from the two natural precursors for the cytotoxicity against leukemia HL60 cells and the multidrug-resistant (MDR) variant HL60R. Six new semi-synthetic triterpenes have been synthetized, fully characterized, and were investigated together with other triterpenes compounds for their pharmacological mechanism of action. The interaction of the more cytotoxic compounds with the nuclear factor kappa B (NF-κB) pathway has been also evaluated with the aid of docking. The lupane-like compounds were more active than the precursor, while the oleane-like compounds showed more complex behavior. Both OA and LU derivatives possess a similar interaction pattern with the p65 subunit of NF-κB, justifying the similar trend in their ability to inhibit the binding of p65 to DNA. Further, some of the derivatives tested were able to increase IκB-α levels preventing the translocation of NF-κB to the nucleus. In conclusion, this study offers a deeper insight on the pharmacological action of triterpenes toward leukemia cells, and it improves the background useful for the development of new anti-cancer drugs. 相似文献
914.
Rayner Keith; Yang Jinmian; Castelhano Monica S.; Liversedge Simon P. 《Canadian Metallurgical Quarterly》2011,26(1):214
Older and younger readers read sentences in which target words were masked 40 to 60 ms after fixation onset. Masking only the target word caused more disruption than did masking each word in the sentence, and this effect was stronger for the younger readers than for the older readers. Although older readers had longer eye fixations than did younger readers, the results indicated that the masking effect was comparable for the 2 groups. However, for both groups, how long the eyes remained in place was strongly influenced by the frequency of the fixated word (even though it had been rapidly replaced by the mask and was no longer there when the eyes did move). This is compelling evidence that for both older and younger readers, cognitive/lexical processing has a very strong influence on when the eyes move in reading. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
915.
Cristina Algieri Chiara Bernardini Fabiana Trombetti Elisa Schena Augusta Zannoni Monica Forni Salvatore Nesci 《International journal of molecular sciences》2022,23(15)
LMNA mutation is associated with type-2 familial partial lipodystrophy (FPLD2). The disease causes a disorder characterized by anomalous accumulation of body fat in humans. The dysfunction at the molecular level is triggered by a lamin A/C mutation, impairing the cell metabolism. In human fibroblasts and preadipocytes, a trend for ATP production, mainly supported by mitochondrial oxidative metabolism, is detected. Moreover, primary cell lines with FPLD2 mutation decrease the mitochondrial ATP production if compared with the control, even if no differences are observed in the oxygen consumption rate of bioenergetic parameters (i.e., basal and maximal respiration, spare respiratory capacity, and ATP turnover). Conversely, glycolysis is only inhibited in FPLD2 fibroblast cell lines. We notice that the amount of ATP produced in the fibroblasts is higher than in the preadipocytes, and likewise in the control, with respect to FPLD2, due to a more active oxidative phosphorylation (OXPHOS) and glycolysis. Moreover, the proton leak parameter, which characterizes the transformation of white adipose tissue to brown/beige adipose tissue, is unaffected by FPLD2 mutation. The metabolic profile of fibroblasts and preadipocytes is confirmed by the ability of these cell lines to increase the metabolic potential of both OXPHOS and glycolysis under energy required independently by the FPLD2 mutation. 相似文献
916.
Hua Wang Heng Huang Monica Basco Molly Lopez Fillia Makedon 《Personal and Ubiquitous Computing》2014,18(1):27-35
Automatic patient thought record categorization (TR) is important in cognitive behavior therapy, which is an useful augmentation of standard clinic treatment for major depressive disorder. Because both collecting and labeling TR data are expensive, it is usually cost prohibitive to require a large amount of TR data, as well as their corresponding category labels, to train a classification model with high classification accuracy. Because in practice we only have very limited amount of labeled and unlabeled training TR data, traditional semi-supervised learning methods and transfer learning methods, which are the most commonly used strategies to deal with the lack of training data in statistical learning, cannot work well in the task of automatic TR categorization. To address this challenge, we propose to tackle the TR categorization problem from a new perspective via self-taught learning, an emerging technique in machine learning. Self-taught learning is a special type of transfer learning. Instead of requiring labeled data from an auxiliary domain that are relevant to the classification task of interest as in traditional transfer learning methods, it learns the inherent structures of the auxiliary data and does not require their labels. As a result, a classifier achieves decent classification accuracy using the limited amount of labeled TR texts, with the assistance from the large amount of text data obtained from some inexpensive, or even no-cost, resources. That is, a cost-effective TR categorization system can be built that may be particularly useful for diagnosis of patients and training of new therapists. By further taking into account the discrete nature input text data, instead of using the traditional Gaussian sparse coding in self-taught learning, we use exponential family sparse coding to better simulate the distribution of the input data. We apply the proposed method to the task of classifying patient homework texts. Experimental results show the effectiveness of the proposed automatic TR classification framework. 相似文献
917.
The Network Architecture of the Connection Machine CM-5 总被引:1,自引:0,他引:1
Charles E. Leiserson Zahi S. Abuhamdeh David C. Douglas Carl R. Feynman Mahesh N. Ganmukhi Jeffrey V. Hill W. Daniel Hillis Bradley C. Kuszmaul Margaret A. St. Pierre David S. Wells Monica C. Wong-Chan Shaw-Wen Yang Robert Zak 《Journal of Parallel and Distributed Computing》1996,33(2):145
The Connection Machine Model CM-5 Supercomputer is a massively parallel computer system designed to offer performance in the range of 1 teraflops (1012floating-point operations per second). The CM-5 obtains its high performance while offering ease of programming, flexibility, and reliability. The machine contains three communication networks: a data network, a control network, and a diagnostic network. This paper describes the organization of these three networks and how they contribute to the design goals of the CM-5. 相似文献
918.
Jonah Ee Hsiang Kua Chun Wei Siow Wee Keng Lim Jeyakumar Masilamani Monica Suryana Tjin Joe Yeong Tony Kiat Hon Lim Toan Thang Phan Alvin Wen Choong Chua 《International journal of molecular sciences》2022,23(16)
Human umbilical cord lining epithelial cells [CLECs) are naïve in nature and can be ethically recovered from cords that are routinely discarded. The success of using oral mucosal epithelial cells for cornea defects hints at the feasibility of treating cutaneous wounds using non-native CLECs. Herein, we characterized CLECs using flow cytometry (FC) and skin organotypic cultures in direct comparison with skin keratinocytes (KCs). This was followed by wound healing study to compare the effects of CLEC application and the traditional use of human skin allografts (HSGs) in a porcine wound model. While CLECs were found to express all the epidermal cell markers probed, the major difference between CLECs and KCs lies in the level of expression (in FC analysis) as well as in the location of expression (of the epithelium in organotypic cultures) of some of the basal cell markers probed. On the pig wounds, CLEC application promoted accelerated healing with no adverse reaction compared to HSG use. Though CLECs, like HSGs, elicited high levels of local and systemic immune responses in the animals during the first week, these effects were tapered off more quickly in the CLEC-treated group. Overall, the in vivo porcine data point to the potential of CLECs as a non-native and safe source of cells to treat cutaneous wounds. 相似文献
919.
Valentina Rizzo Nadia Ferlazzo Monica Curr Gaetano Isola Marco Matarese Maria Paola Bertuccio Daniela Caccamo Giovanni Matarese Riccardo Ientile 《International journal of molecular sciences》2021,22(5)
Several studies have demonstrated a relevant role of intestinal epithelial cells in the immune response and in chronic inflammatory conditions, including ulcers, colitis, and Crohn’s disease. Baicalin (BA), extracted from the root of Scutellaria baicalensis, has various beneficial healthy effects, including anti-inflammatory activity. However, few studies have evaluated BA effects on autophagic signaling in epithelial cell response to inflammatory stimuli. To explore possible beneficial effects of BA, HT-29 cells were exposed to lipopolysaccharide (LPS), in presence or absence of BA, for 4 h. We evaluated mRNA levels of autophagy-related genes and cytokines, triggering inflammatory response. Furthermore, the expression of claudin 1, involved in the regulation of paracellular permeability was analyzed. BA treatment repressed LPS-induced expression of TNF-α and IL-1β. The down-regulation of autophagy-related genes induced by LPS was counteracted by cell pretreatment with BA. Under these conditions, BA reduced the NF-κB activation caused by LPS. Also, BA restored mRNA and protein levels of claudin 1, which were reduced by LPS. In conclusion, in intestinal epithelial cells BA regulates the NF-κB activation and modulates both autophagic and inflammatory processes, leading to an improvement of paracellular permeability. These results suggest that the anti-inflammatory effects of BA can be associated to the regulation of autophagic flux. 相似文献
920.
Shuai Ren Rafael Jiménez-Flores Maria Monica Giusti 《Comprehensive Reviews in Food Science and Food Safety》2021,20(6):5992-6011
Anthocyanins (ACN) are natural pigments that produce bright red, blue, and purple colors in plants and can be used to color food products. However, ACN sensitivity to different factors limits their applications in the food industry. Whey protein (WP), a functional nutritional additive, has been shown to interact with ACN and improve the color, stability, antioxidant capacity, bioavailability, and other functional properties of the ACN-WP complex. The WP's secondary structure is expected to unfold due to heat treatment, which may increase its binding affinity with ACN. Different ACN structures will also have different binding affinity with WP and their interaction mechanism may also be different. Circular dichroism (CD) spectroscopy and Fourier transform infrared (FTIR) spectroscopy show that the WP secondary structure changes after binding with ACN. Fluorescence spectroscopy shows that the WP maximum fluorescence emission wavelength shifts, and the fluorescence intensity decreases after interaction with ACN. Moreover, thermodynamic analysis suggests that the ACN-WP binding forces are mainly hydrophobic interactions, although there is also evidence of electrostatic interactions and hydrogen bonding between ACN and WP. In this review, we summarize the information available on ACN-WP interactions under different conditions and discuss the impact of different ACN chemical structures and of WP conformation changes on the affinity between ACN and WP. This summary helps improve our understanding of WP protection of ACN against color degradation, thus providing new tools to improve ACN color stability and expanding the applications of ACN and WP in the food and pharmacy industries. 相似文献