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951.
Ramona DAmico Roberta Fusco Rosalba Siracusa Daniela Impellizzeri Alessio Filippo Peritore Enrico Gugliandolo Livia Interdonato Andrea Maria Sforza Rosalia Crupi Salvatore Cuzzocrea Tiziana Genovese Marika Cordaro Rosanna Di Paola 《International journal of molecular sciences》2021,22(12)
Fibromyalgia is a chronic condition characterized by persistent widespread pain that significantly reduces quality of life in patients. The purinergic P2X7 receptor (P2X7R) seems to be involved in different pain states and neuroinflammation. The purpose of this study is to investigate the positive effects of P2X7R inhibition by the antagonist Brilliant Blue G (BBG) in a rat model of reserpine-induced fibromyalgia. Sprague–Dawley male rats were injected with 1 mg/kg of reserpine for three consecutive days. Later, animals were administered BBG (50 mg/kg) intraperitoneally for seven days. Reserpine injections induced a significant increase in pain pro-inflammatory mediators as well as a significant increase in neuroinflammation. Chronic pain, in turn, led to depressive-like symptoms and reduced neurogenesis. Blockage of P2X7R by BBG administrations is able to attenuate the behavioral deficits, pain mediators and microglial activation induced by reserpine injection. Additionally, BBG prevents NLRP3 inflammasome activation and consequently the release of active interleukin (IL)-1 and IL-18, involved in the activation of nociceptors. In conclusion, these results suggest that inhibition of P2X7R should be further investigated to develop a potential approach for the management of fibromyalgia. 相似文献
952.
Maria Giovanna Parisi Annalisa Grimaldi Nicol Baranzini Claudia La Corte Mariano Dara Daniela Parrinello Matteo Cammarata 《International journal of molecular sciences》2021,22(11)
Given the anatomical simplicity and the extraordinary ability to regenerate missing parts of the body, Cnidaria represent an excellent model for the study of the mechanisms regulating regenerative processes. They possess the mesoglea, an amorphous and practically acellular extracellular matrix (ECM) located between the epidermis and the gastrodermis of the body and tentacles and consists of the same molecules present in the ECM of vertebrates, such as collagen, laminin, fibronectin and proteoglycans. This feature makes cnidarians anthozoans valid models for understanding the ECM role during regenerative processes. Indeed, it is now clear that its role in animal tissues is not just tissue support, but instead plays a key role during wound healing and tissue regeneration. This study aims to explore regenerative events after tentacle amputation in the Mediterranean anemone Anemonia viridis, focusing in detail on the reorganization of the ECM mesoglea. In this context, both enzymatic, biometric and histological experiments reveal how this gelatinous connective layer plays a fundamental role in the correct restoration of the original structures by modifying its consistency and stiffness. Indeed, through the deposition of collagen I, it might act as a scaffold and as a guide for the reconstruction of missing tissues and parts, such as amputated tentacles. 相似文献
953.
Segmented biopolyurethanes for medical applications 总被引:1,自引:0,他引:1
Doina Macocinschi Daniela Filip Stelian Vlad Mariana Cristea Maria Butnaru 《Journal of materials science. Materials in medicine》2009,20(8):1659-1668
Polyurethanes are one of the most popular groups of biomaterials applied for medical devices. Their segmented block copolymeric
character endows them a wide range of versatility in terms of tailoring their physical properties, blood and tissue compatibility.
Polyester- and polyether-urethanes have been modified with hydroxypropyl cellulose aiming the change of their surface and
bulk characteristics to confer them biomaterial qualities. In this respect, dynamic contact angle measurements, dynamic mechanical
analyses accompanied by mechanical testing have been done. Platelet adhesion test has been carried out in vitro and the use
of hydroxypropyl cellulose in the polyurethane matrix reduces the platelet adhesion and therefore recommends them as candidates
for biocompatible materials. 相似文献
954.
We wish for robots to manipulate objects and move flexibly in three-dimensional spaces. We describe a robot that can move on a web of surfaces oriented around arbitrary directions in three-space and a set of control algorithms that implements motion in three-dimensions. The robot can manipulate objects in three dimensions while moving, by using the same set of physical resources and control algorithms. This robot is an inchworm-like robot with a simple, modular, and flexible design. Finally, we discuss our experiments. 相似文献
955.
Roberta Zuntini Elena Bonora Laura Maria Pradella Laura Benedetta Amato Michele Vidone Sara De Fanti Irene Catucci Laura Cortesi Veronica Medici Simona Ferrari Giuseppe Gasparre Paolo Peterlongo Marco Sazzini Daniela Turchetti 《International journal of molecular sciences》2021,22(11)
The NBN gene has been included in breast cancer (BC) multigene panels based on early studies suggesting an increased BC risk for carriers, though not confirmed by recent research. To evaluate the impact of NBN analysis, we assessed the results of NBN sequencing in 116 BRCA-negative BC patients and reviewed the literature. Three patients (2.6%) carried potentially relevant variants: two, apparently unrelated, carried the frameshift variant c.156_157delTT and another one the c.628G>T variant. The latter was subsequently found in 4/1390 (0.3%) BC cases and 8/1580 (0.5%) controls in an independent sample, which, together with in silico predictions, provided evidence against its pathogenicity. Conversely, the rare c.156_157delTT variant was absent in the case-control set; moreover, a 50% reduction of NBN expression was demonstrated in one carrier. However, in one family it failed to co-segregate with BC, while the other carrier was found to harbor also a probably pathogenic TP53 variant that may explain her phenotype. Therefore, the c.156_157delTT, although functionally deleterious, was not supported as a cancer-predisposing defect. Pathogenic/likely pathogenic NBN variants were detected by multigene panels in 31/12314 (0.25%) patients included in 15 studies. The risk of misinterpretation of such findings is substantial and supports the exclusion of NBN from multigene panels. 相似文献
956.
This study develops and analyzes an original methodology for the simulation and prediction of space heating energy consumption in buildings connected to a district heating system, characterized by lack of individual control systems for end-users. The identification of the input parameters is based on both classical engineering equations and statistical analysis of collected data. Two main factors play important roles in the model: (i) climate and (ii) human behavior. Model validation was undertaken through the analysis of field data collected during the winter, via a monitoring system working in a partially-controlled district heating system. The comparison between the results obtained with the proposed model versus classical methods points out the possibility to implement, using the proposed methodology, management policies for a district that offer significant cost-effective energy savings opportunities. 相似文献
957.
Preparation and characterization of blends of recycled polystyrene with cassava starch 总被引:1,自引:0,他引:1
Tais A. P. F. Pimentel Jussara A. Durães Adriana L. Drummond Daniela Schlemmer Rosana Falcão Maria José Araújo Sales 《Journal of Materials Science》2007,42(17):7530-7536
Secondary recycling is an alternative to solve at least part of the worldwide pollution problem caused by persistence of petrochemical
plastic materials in the environment. In this work we report the secondary recycling of disposable polystyrene (PS) using
cassava starch (Manihot esculenta Crantz) and a natural plasticizer extracted from a palm tree of the Amazon: Buriti (Mauritia flexuosa L.) oil. 13C-NMR spectroscopy reveals incorporation of the oil in the polymer matrix. Although phase separation had occurred, SEM depicts
a very good dispersion of the thermoplastic starch (TPS) in the PS matrix with distinct domains. Thermal analyses indicate
smaller thermal stability of the PS/TPS blends compared to PS and that possess intermediate characteristics between the pure
PS and TPS, confirmed by DRX. Kinetic study shows a lowering of the activation energy for the thermal degradation of the blends. 相似文献
958.
959.
Mattia P. Arena Graziano Caggianiello Daniela Fiocco Pasquale Russo Michele Torelli Giuseppe Spano Vittorio Capozzi 《International journal of molecular sciences》2014,15(2):3025-3039
Currently, the majority of prebiotics in the market are derived from non-digestible oligosaccharides. Very few studies have focused on non-digestible long chain complex polysaccharides in relation to their potential as novel prebiotics. Cereals β-glucans have been investigated for immune-modulating properties and beneficial effects on obesity, cardiovascular diseases, diabetes, and cholesterol levels. Moreover, β-glucans have been reported to be highly fermentable by the intestinal microbiota in the caecum and colon, and can enhance both growth rate and lactic acid production of microbes isolated from the human intestine. In this work, we report the effects of food matrices containing barley β-glucans on growth and probiotic features of four Lactobacillus strains. Such matrices were able to improve the growth rate of the tested bacteria both in unstressed conditions and, importantly, after exposure to in vitro simulation of the digestive tract. Moreover, the effect of β-glucans-containing food on bacterial adhesion to enterocyte-like cells was analyzed and a positive influence on probiotic-enterocyte interaction was observed. 相似文献
960.
Dr. Daniela Schulz Prof. Dr. Andrea Rentmeister 《Chembiochem : a European journal of chemical biology》2014,15(16):2342-2347
Over recent years, click reactions have become recognized as valuable and flexible tools to label biomacromolecules such as proteins, nucleic acids, and glycans. Some of the developed strategies can be performed not only in aqueous solution but also in the presence of cellular components, as well as on (or even in) living cells. These labeling strategies require the initial, specific modification of the target molecule with a small, reactive moiety. In the second step, a click reaction is used to covalently couple a reporter molecule to the biomolecule. Depending on the type of reporter, labeling by the click reaction can be used in many different applications, ranging from isolation to functional studies of biomacromolecules. In this minireview, we focus on labeling strategies for RNA that rely on the click reaction. We first highlight click reactions that have been used successfully to label modified RNA, and then describe different strategies to introduce the required reactive groups into target RNA. The benefits and potential limitations of the strategies are critically discussed with regard to possible future developments. 相似文献