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91.
Barbara Iovine Maria Luigia Iannella Franco Gasparri Valentina Giannini Giuseppe Monfrecola Maria Assunta Bevilacqua 《International journal of molecular sciences》2012,13(12):16444-16456
Isoflavones exist in nature predominantly as glucosides such as daidzin or genistin and are rarely found in their corresponding aglycone forms daidzein and genistein. The metabolism and absorption of isoflavones ingested with food is well documented, but little is known about their use as topical photo-protective agents. The aim of this study was to investigate in a comparative analysis the photo-protective effects of isoflavones in both their aglycone and glucoside forms. In human skin fibroblasts irradiated with 60 mJ/cm2 ultraviolet B (UVB), we measured the expression levels of COX-2 and Gadd45, which are involved in inflammation and DNA repair, respectively. We also determined the cellular response to UVB-induced DNA damage using the comet assay. Our findings suggest that both the isoflavone glucosides at a specific concentration and combination with an aglycone mixture exerted an anti-inflammatory and photo-protective effect that prevented 41% and 71% of UVB-induced DNA damage, respectively. The advantages of using either isoflavone glucosides or an aglycone mixture in applications in the field of dermatology will depend on their properties and their different potential uses. 相似文献
92.
Carola Palmerini Luca Piscitani Giuseppina Bologna Chiara Riganti Paola Lanuti Domitilla Mandatori Lorenzo Di Liberato Giorgia Di Fulvio Vittorio Sirolli Giulia Renda Caterina Pipino Marco Marchisio Mario Bonomini Assunta Pandolfi Natalia Di Pietro 《International journal of molecular sciences》2021,22(6)
Red blood cells (RBCs) have been found to synthesize and release both nitric oxide (NO) and cyclic guanosine monophosphate (cGMP), contributing to systemic NO bioavailability. These RBC functions resulted impaired in chronic kidney disease (CKD). This study aimed to evaluate whether predialysis (conservative therapy, CT) and dialysis (peritoneal dialysis, PD; hemodialysis, HD) therapies used during CKD progression may differently affect NO-synthetic pathway in RBCs. Our data demonstrated that compared to PD, although endothelial-NO-synthase activation was similarly increased, HD and CT were associated to cGMP RBCs accumulation, caused by reduced activity of cGMP membrane transporter (MRP4). In parallel, plasma cGMP levels were increased by both CT and HD and they significantly decreased after hemodialysis, suggesting that this might be caused by reduced cGMP renal clearance. As conceivable, compared to healthy subjects, plasma nitrite levels were significantly reduced by HD and CT but not in patients on PD. Additionally, the increased carotid intima-media thickness (IMT) values did not reach the significance exclusively in patients on PD. Therefore, our results show that PD might better preserve the synthetic NO-pathway in CKD-erythrocytes. Whether this translates into a reduced development of uremic vascular complications requires further investigation. 相似文献
93.
Antonella Rosa Carlo Ignazio Giovanni Tuberoso Angela Atzeri Maria Paola Melis Ersilia Bifulco Maria Assunta Dessì 《Food chemistry》2011
The antioxidant activity of several honeys was evaluated considering the different contribution of entire samples. The strawberry tree honey emerged as the richest in total phenols and the most active honey in the DPPH and FRAP tests, and could protect cholesterol against oxidative degradation (140 °C). Homogentisic acid (2,5-dihydroxyphenylacetic acid, HGA), the main phenolic compound from strawberry tree honey, showed interesting antioxidant and antiradical activities, and protective effect against thermal-cholesterol degradation, comparable to those of well known antioxidants. Moreover, the pre-treatment with HGA significantly preserved liposomes and LDL from Cu2+-induced oxidative damage at 37 °C for 2 h, inhibiting the reduction of polyunsaturated fatty acids and cholesterol and the increase of their oxidative products. This phenol had no toxic effect in human intestinal epithelial Caco-2 cells within the concentration range tested (5–1000 μM). HGA was able to pass through the Caco-2 monolayers, the apparent permeability coefficients (Papp) in the apical-to-basolateral and basolateral-to-apical direction were 3.48 ± 1.22 × 10−6 and 2.18 ± 0.34 × 10−6 cm/s, respectively, suggesting a passive diffusion pathway as the dominating process. The results of the work qualify HGA as natural antioxidant, able to exert a significant in vitro protective effect and to contribute to the strawberry tree honey antioxidant activity. 相似文献
94.
今年的Wescon2004国际技术会议Wescon于2004.年9月21日至23日在美国加利福尼亚州阿纳海姆的阿纳海姆会议中心举行,与EnterpriseIntegrationExpo(研讨国防工业中以网络为中心的运作模式所产生的影响)和NANOWord(一项以纳米技术的教育、培训和商业应用展示为主线的活动)同地举行。来自众多学术领域的参展机构展示了其最新产品和技术。 相似文献
95.
Gennaro Raiola Susana Sanchez Restrepo Pauline Chevalier Pedro Rodriguez-Ayerbe Xavier Lamy Sami Tliba Freek Stulp 《Autonomous Robots》2018,42(5):1037-1051
Virtual guiding fixtures constrain the movements of a robot to task-relevant trajectories, and have been successfully applied to, for instance, surgical and manufacturing tasks. Whereas previous work has considered guiding fixtures for single tasks, in this paper we propose a library of guiding fixtures for multiple tasks, and propose methods for (1) creating and adding guides based on machine learning; (2) selecting guides on-line based on probabilistic implementation of guiding fixtures; (3) refining existing guides based on an incremental learning method. We demonstrate in an industrial task that a library of guiding fixtures provides an intuitive haptic interface for joint human–robot completion of tasks, and improves performance in terms of task execution time, mental workload and errors. 相似文献
96.
Juuso Paajanen Raphael Bueno Assunta De Rienzo 《International journal of molecular sciences》2022,23(21)
Pleural mesothelioma (PM) is a rare and aggressive disease that arises from the mesothelial cells lining the pleural cavity. Approximately 80% of PM patients have a history of asbestos exposure. The long latency period of 20–40 years from the time of asbestos exposure to diagnosis, suggests that multiple somatic genetic alterations are required for the tumorigenesis of PM. The genomic landscape of PM has been characterized by inter- and intratumor heterogeneity associated with the impairment of tumor suppressor genes such as CDKN2A, NF2, and BAP1. Current systemic therapies have shown only limited efficacy, and none is approved for patients with relapsed PM. Advances in understanding of the molecular landscape of PM has facilitated several biomarker-driven clinical trials but so far, no predictive biomarkers for targeted therapies are in clinical use. Recent advances in the PM genetics have provided optimism for successful molecular strategies in the future. Here, we summarize the molecular mechanism underlying PM pathogenesis and review potential therapeutic targets. 相似文献
97.
98.
Monti MC Casapullo A Cavasotto CN Napolitano A Riccio R 《Chembiochem : a European journal of chemical biology》2007,8(13):1585-1591
Several marine terpenoids that contain at least one reactive aldehyde group, such as manoalide and its congeners, possess interesting anti-inflammatory activities that are mediated by the covalent inactivation of secretory phospholipase A(2) (sPLA(2)). Scalaradial, a 1,4-dialdehyde marine terpenoid that was isolated from the sponge Cacospongia mollior, is endowed with a relevant anti-inflammatory profile, both in vitro and in vivo, through selective sPLA(2) inhibition. Due to its peculiar dialdehyde structural feature, it has been proposed that scalaradial exerts its enzymatic inactivation by means of an irreversible covalent modification of its target. In the context of our on-going research on anti-PLA(2) natural products and their interaction at a molecular level, we studied scalaradial in an attempt to shed more light on the molecular mechanism of its PLA(2) inhibition. A detailed analysis of the reaction profile between scalaradial and bee venom PLA(2), a model sPLA(2) that shares a high structural homology with the human synovial enzyme, was performed by a combination of spectroscopic techniques, chemical reactions (selective modifications, biomimetic reactions), and classical protein chemistry (such as proteolytic digestion, HPLC and mass spectrometry), along with molecular modeling studies. Unexpectedly, our data clearly indicated the noncovalent forces to be the leading event in the PLA(2) inactivation process; thus, the covalent modification of the enzyme emerges as only a minor side event in the ligand-enzyme interaction. The overall picture might be useful in the design of SLD analogues as new potential anti-inflammatory compounds that target sPLA(2) enzymes. 相似文献
99.
Paola Scano Antonella Rosa Simone Mereu Cristina Piras Angela Atzeri M. Assunta Dessi 《European Journal of Lipid Science and Technology》2010,112(12):1369-1374
Mullet bottarga is a food delicacy obtained by salting and drying the intact roes of mullet (Mugil spp.). The fatty acid and fatty alcohol compositions of different samples of bottarga were studied by means of gas chromatography (GC) and multivariate analysis (MVA). High percentages of beneficial n‐3 PUFA, among which docosahexaenoic acid (DHA) (22:6n‐3, 11.9%) and eicosapentaenoic acid (EPA) (20:5n‐3, 8.6%), were detected. Differences in the concentrations of unsaturated FA and FAL were observed among samples, while saturated components showed little variations. On the other hand, the total contents of saturated, monounsaturated and polyunsaturated components were similar. The principal component analysis loadings bi‐plot showed that n‐6 PUFA concentrations were inversely correlated to those of n‐3 PUFA, except for DHA that showed no correlations. Correlations between FAL concentrations were also observed. Furthermore, integrating our GC data with those from the literature on mullet and tuna bottarga, the MVA showed that both bottarga typologies exhibit a similar trend in the FA distribution and that 16:0 and 16:1n‐7 FA are the variables with the highest discriminant power. In this work, we demonstrated the usefulness of the application of MVA to GC data to extract meaningful information otherwise hidden in the amount of data. 相似文献
100.
Pascal Wolfer Maria Laura Santarelli Luigi Vaccaro Liyang Yu Thomas D. Anthopoulos Paul Smith Natalie Stingelin Assunta Marrocchi 《Organic Electronics》2011,12(11):1886-1892
Blends of chemically readily accessible, small-molecular arylacetylene derivatives with poly(vinylidene fluoride) (PVDF) are presented that allow reliable solution processing of field-effect transistor (FET) architectures with electronic characteristics comparable to those of the neat semiconductors. We demonstrate that having the chemical means and corresponding processing protocols to control solid-state microstructures by either adjusting the chemical nature of the organic semiconductor, blend composition or deposition temperature, permit straight-forward comparison between materials and allow probing if electronic characteristics are affected by the chemical structure of the organic semiconductor and/or selected processing protocols. 相似文献