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排序方式: 共有3283条查询结果,搜索用时 15 毫秒
61.
Lorenza Marinaccio Azzurra Stefanucci Giuseppe Scioli Alice Della Valle Gokhan Zengin Angelo Cichelli Adriano Mollica 《International journal of molecular sciences》2022,23(6)
Elastases are a broad group of enzymes involved in the lysis of elastin, the main component of elastic fibres. They are produced and released in the human body, mainly by neutrophils and the pancreas. The imbalance between elastase activity and its endogenous inhibitors can cause different illnesses due to their excessive activity. The main aim of this review is to provide an overview of the latest advancements on the identification, structures and mechanisms of action of peptide human neutrophil elastase inhibitors isolated from natural sources, such as plants, animals, fungi, bacteria and sponges. The discovery of new elastase inhibitors could have a great impact on the pharmaceutical development of novel drugs through the optimization of the natural lead compounds. Bacteria produce mainly cyclic peptides, while animals provide for long and linear amino acid sequences. Despite their diverse natural sources, these elastase inhibitors show remarkable IC50 values in a range from nM to μM values, thus representing an interesting starting point for the further development of potent bioactive compounds on human elastase enzymes. 相似文献
62.
63.
A comprehensive meta‐analysis on dietary flavonoid and lignan intake and cancer risk: Level of evidence and limitations 下载免费PDF全文
64.
Bonzini S Verro R Otto S Lazzaro L Finizio A Zanin G Vighi M 《Environmental science & technology》2006,40(24):7561-7569
A GIS-based procedure for predicting pesticide exposure in surface waters has been applied on a pilot river basin characterized by intensive agricultural activity. The predictive approach has been validated through experimental monitoring, performed by collecting manual and automatic water samples during the productive season. Five active ingredients (terbuthylazine, metolachlor, alachlor, linuron, fenitrothion) were selected for analysis to validate the predictive approach. Comparison between predicted and experimental values showed good agreement for terbuthylazine and metolachlor (used in large volumes within the basin), demonstrating the reliability of the approach. However, some anomalous results were obtained for some of the other chemicals, which serve to highlight the difficulties in getting reliable input data, in particular on application patterns (rate and time). Furthermore, the value of mapping pesticide exposure on the medium-large scale is described, and the limitations of the reported predictive approach are discussed. 相似文献
65.
Gabriele Mocciaro Simona DAmore Benjamin Jenkins Richard Kay Antonio Murgia Luis Vicente Herrera-Marcos Stefanie Neun Alice P. Sowton Zoe Hall Susana Alejandra Palma-Duran Giuseppe Palasciano Frank Reimann Andrew Murray Patrizia Suppressa Carlo Sabb Antonio Moschetta Albert Koulman Julian L. Griffin Michele Vacca 《International journal of molecular sciences》2022,23(12)
The metabolic syndrome (MetS) is a cluster of cardiovascular risk factors characterised by central obesity, atherogenic dyslipidaemia, and changes in the circulating lipidome; the underlying mechanisms that lead to this lipid remodelling have only been partially elucidated. This study used an integrated “omics” approach (untargeted whole serum lipidomics, targeted proteomics, and lipoprotein lipidomics) to study lipoprotein remodelling and HDL composition in subjects with central obesity diagnosed with MetS (vs. controls). Compared with healthy subjects, MetS patients showed higher free fatty acids, diglycerides, phosphatidylcholines, and triglycerides, particularly those enriched in products of de novo lipogenesis. On the other hand, the “lysophosphatidylcholines to phosphatidylcholines” and “cholesteryl ester to free cholesterol” ratios were reduced, pointing to a lower activity of lecithin cholesterol acyltransferase (LCAT) in MetS; LCAT activity (directly measured and predicted by lipidomic ratios) was positively correlated with high-density lipoprotein cholesterol (HDL-C) and negatively correlated with body mass index (BMI) and insulin resistance. Moreover, many phosphatidylcholines and sphingomyelins were significantly lower in the HDL of MetS patients and strongly correlated with BMI and clinical metabolic parameters. These results suggest that MetS is associated with an impairment of phospholipid metabolism in HDL, partially led by LCAT, and associated with obesity and underlying insulin resistance. This study proposes a candidate strategy to use integrated “omics” approaches to gain mechanistic insights into lipoprotein remodelling, thus deepening the knowledge regarding the molecular basis of the association between MetS and atherosclerosis. 相似文献
66.
Annamaria Mancini Daniela Vitucci Giuseppe Labruna Stefania Orr Pasqualina Buono 《International journal of molecular sciences》2022,23(14)
Human skeletal muscle contains three different types of fibers, each with a different metabolism. Exercise differently contributes to differentiation and metabolism in human myoblast cells. The aims of the present study were to investigate the effects of different types of chronic training on the human LHCN-M2 myoblast cell bioenergetic profile during differentiation in real time and on the ROS overproduction consequent to H2O2 injury. We demonstrated that exercise differently affects the myoblast bioenergetics: aerobic exercise induced the most efficient glycolytic and oxidative capacity and proton leak reduction compared to untrained or anaerobic trained sera-treated cells. Similarly, ROS overproduction after H2O2 stress was lower in cells treated with differently trained sera compared to untrained sera, indicating a cytoprotective effect of training on the reduction of oxidative stress, and thus the promotion of longevity. In conclusion, for the first time, this study has provided knowledge regarding the modifications induced by different types of chronic training on human myoblast cell bioenergetics during the differentiation process in real time, and on ROS overproduction due to stress, with positive implications in terms of longevity. 相似文献
67.
Federica Balzano Gloria Uccello-Barretta Giuseppe Sicoli Letizia Vanni Alessandra Recchimurzo Federica Aiello 《International journal of molecular sciences》2022,23(21)
Cyclodextrin derivatives constitute a powerful class of auxiliary agents for the discrimination of apolar chiral substrates. Both host–guest inclusion phenomena and interactions with the derivatizing groups located on the surface of the macrocycle could drive the enantiodiscrimination; thus, it is important to understand the role that these processes play in the rational design of new chiral selectors. The purpose of this study is to compare via nuclear magnetic resonance (NMR) spectroscopy the efficiency of silylated-acetylated α-, β-, and γ-cyclodextrins in the chiral discrimination of 1,1,1,3,3-pentafluoro-2-(fluoromethoxy)-3-methoxypropane (compound B) and methyl 2-chloropropionate (MCP). NMR DOSY (Diffusion Ordered SpectroscopY) experiments were conducted for the determination of the bound molar fractions and the association constants, whereas ROESY (Rotating-frame Overhauser Enhancement SpectroscopY) measurements provided information on the hosts’ conformation and on the interaction phenomena with the guests. Compound B, endowed with fluorinated moieties, is not deeply included due to attractive Si-F interactions occurring at the external surface of the cyclodextrins. Therefore, a low selectivity toward the size of cyclodextrin cavity is found. By contrast, enantiodiscrimination of MCP relies on the optimal fitting between the size of the guest and that of the cyclodextrin cavity. 相似文献
68.
The ATP-binding site of protein kinase CK2 holds a positive electrostatic area and conserved water molecules 总被引:1,自引:0,他引:1
Battistutta R Mazzorana M Cendron L Bortolato A Sarno S Kazimierczuk Z Zanotti G Moro S Pinna LA 《Chembiochem : a European journal of chemical biology》2007,8(15):1804-1809
CK2 is a highly pleiotropic Ser/Thr protein kinase that is able to promote cell survival and enhance the tumour phenotype under specific circumstances. We have determined the crystal structure of three new complexes with tetrabromobenzimidazole derivatives that display K(i) values between 0.15 and 0.30 microM. A comparative analysis of these data with those of four other inhibitors of the same family revealed the presence of some highly conserved water molecules in the ATP-binding site. These waters reside near Lys68, in an area with a positive electrostatic potential that is able to attract and orient negatively charged ligands. The presence of this positive region and two unique bulky residues that are typical of CK2, Ile66 and Ile174, play a critical role in determining the ligand orientation and binding selectivity. 相似文献
69.
Fabiana Piscitelli Roberto Coccurello Antonio Totaro Alessandro Leuti Giacomo Giacovazzo Roberta Verde Emanuela Rossi Michele Podaliri Vulpiani Nicola Ferri Roberto Giacominelli Stuffler Vincenzo Di Marzo Sergio Oddi Tiziana Bisogno Mauro Maccarrone 《European Journal of Lipid Science and Technology》2019,121(10)
70.
Walter Navarrini Tommaso Brivio Dmitrij Capobianco Maria Vittoria Diamanti Mariapia Pedeferri Luca Magagnin Giuseppe Resnati 《Journal of Coatings Technology and Research》2011,8(2):153-160
In this study amorphous fluorinated coatings applied to anodized titanium surface have been investigated. A copolymer between
tetrafluoroethylene and perfluoro-4-trifluoromethoxy-1,3-dioxole (AD60) and two perfluoropolyether containing ammonium phosphate
(F10) or triethoxysilane (S10) functionalities have been tested. To estimate the color alteration of the anodized titanium
surfaces due to the application of the coatings, spectrophotometric analyses have been made. Water and n-dodecane contact angles as well as apparent surface energy have been evaluated. Ellipsometry and atomic force microscopy
data have been used to measure the thickness of the fluorinated coatings. A tailored mechanical preliminary test has also
been explored to evaluate the adhesion of the coatings on the anodized titanium surface. The resistance to surface soiling
with castor oil was also preliminarily investigated. The fluorinated coating tested on anodized titanium showed a low apparent
surface energy and high chromatic aspect conservation, this is particularly evident for the titanium anodized coated with
triethoxysilane functionalities fluoropolymers S10. 相似文献