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排序方式: 共有4305条查询结果,搜索用时 15 毫秒
21.
Silvio Borrelli Ida Matarazzo Eugenio Lembo Laura Peccarino Claudia Annoiato Maria Rosaria Scognamiglio Andrea Foderini Chiara Ruotolo Aldo Franculli Federica Capozzi Pavlo Yavorskiy Fatme Merheb Michele Provenzano Gaetano La Manna Luca De Nicola Roberto Minutolo Carlo Garofalo 《International journal of molecular sciences》2022,23(12)
Increasing potassium intake ameliorates blood pressure (BP) and cardiovascular (CV) prognoses in the general population; therefore the World Health Organization recommends a high-potassium diet (90–120 mEq/day). Hyperkalaemia is a rare condition in healthy individuals due to the ability of the kidneys to effectively excrete dietary potassium load in urine, while an increase in serum K+ is prevalent in patients with chronic kidney disease (CKD). Hyperkalaemia prevalence increases in more advanced CKD stages, and is associated with a poor prognosis. This scenario generates controversy on the correct nutritional approach to hyperkalaemia in CKD patients, considering the unproven link between potassium intake and serum K+ levels. Another concern is that drug-induced hyperkalaemia leads to the down-titration or withdrawal of renin-angiotensin system inhibitors (RASI) and mineralocorticoids receptors antagonists (MRA) in patients with CKD, depriving these patients of central therapeutic interventions aimed at delaying CKD progression and decreasing CV mortality. The new K+-binder drugs (Patiromer and Sodium-Zirconium Cyclosilicate) have proven to be adequate and safe therapeutic options to control serum K+ in CKD patients, enabling RASI and MRA therapy, and possibly, a more liberal intake of fruit and vegetables. 相似文献
22.
Marianna Barbalinardo Marta Giannelli Ludovica Forcini Barbara Luppi Anna Donnadio Maria Luisa Navacchia Giampiero Ruani Giovanna Sotgiu Annalisa Aluigi Roberto Zamboni Tamara Posati 《International journal of molecular sciences》2022,23(12)
Skin disorders are widespread around the world, affecting people of all ages, and oxidative stress represents one of the main causes of alteration in the normal physiological parameters of skin cells. In this work, we combined a natural protein, fibroin, with antioxidant compounds extracted in water from pomegranate waste. We demonstrate the effective and facile fabrication of bioactive and eco-sustainable films of potential interest for skin repair. The blended films are visually transparent (around 90%); flexible; stable in physiological conditions and in the presence of trypsin for 12 days; able to release the bioactive compounds in a controlled manner; based on Fickian diffusion; and biocompatible towards the main skin cells, keratinocytes and fibroblasts. Furthermore, reactive oxygen species (ROS) production tests demonstrated the high capacity of our films to reduce the oxidative stress induced in cells, which is responsible for various skin diseases. 相似文献
23.
24.
Carlos Dariel Rodriguez-Marquez Susana Arteaga-Marin Andrea Rivas-Snchez Renata Autrique-Hernndez Roberto Castro-Muoz 《International journal of molecular sciences》2022,23(11)
Since it is known that hyaluronic acid contributes to soft tissue growth, elasticity, and scar reduction, different strategies of producing HA have been explored in order to satisfy the current demand of HA in pharmaceutical products and formulations. The current interest deals with production via bacterial and yeast fermentation and extraction from animal sources; however, the main challenge is the right extraction technique and strategy since the original sources (e.g., fermentation broth) represent a complex system containing a number of components and solutes, which complicates the achievement of high extraction rates and purity. This review sheds light on the main pathways for the production of HA, advantages, and disadvantages, along with the current efforts in extracting and purifying this high-added-value molecule from different sources. Particular emphasis has been placed on specific case studies attempting production and successful recovery. For such works, full details are given together with their relevant outcomes. 相似文献
25.
Agnese Filippello Stefania Di Mauro Alessandra Scamporrino Sebastiano Alfio Torrisi Gian Marco Leggio Antonino Di Pino Roberto Scicali Maurizio Di Marco Roberta Malaguarnera Francesco Purrello Salvatore Piro 《International journal of molecular sciences》2022,23(14)
Intestinal cell dysfunctions involved in obesity and associated diabetes could be correlated with impaired intestinal cell development. To date, the molecular mechanisms underlying these dysfunctions have been poorly investigated because of the lack of a good model for studying obesity. The main aim of this study was to investigate the effects of lipotoxicity on intestinal cell differentiation in small intestinal organoid platforms, which are used to analyze the regulation of cell differentiation. Mouse intestinal organoids were grown in the presence/absence of high palmitate concentrations (0.5 mM) for 48 h to simulate lipotoxicity. Palmitate treatment altered the expression of markers involved in the differentiation of enterocytes and goblet cells in the early (Hes1) and late (Muc2) phases of their development, respectively, and it modified enterocytes and goblet cell numbers. Furthermore, the expression of enteroendocrine cell progenitors (Ngn3) and I cells (CCK) markers was also impaired, as well as CCK-positive cell numbers and CCK secretion. Our data indicate, for the first time, that lipotoxicity simultaneously influences the differentiation of specific intestinal cell types in the gut: enterocytes, goblet cells and CCK cells. Through this study, we identified novel targets associated with molecular mechanisms affected by lipotoxicity that could be important for obesity and diabetes therapy. 相似文献
26.
Valentina Masola Mario Bonomini Silvio Borrelli Lorenzo Di Liberato Luigi Vecchi Maurizio Onisto Giovanni Gambaro Roberto Palumbo Arduino Arduini 《International journal of molecular sciences》2022,23(9)
Peritoneal dialysis (PD) is an efficient renal replacement therapy for patients with end-stage renal disease. Even if it ensures an outcome equivalent to hemodialysis and a better quality of life, in the long-term, PD is associated with the development of peritoneal fibrosis and the consequents patient morbidity and PD technique failure. This unfavorable effect is mostly due to the bio-incompatibility of PD solution (mainly based on high glucose concentration). In the present review, we described the mechanisms and the signaling pathway that governs peritoneal fibrosis, epithelial to mesenchymal transition of mesothelial cells, and angiogenesis. Lastly, we summarize the present and future strategies for developing more biocompatible PD solutions. 相似文献
27.
Antonio Raffo Sergio Di Falco Roberto Menozzi Giorgio Vannini 《Microelectronics Reliability》2011,51(2):235-239
Electron device degradation, although not directly accounted for, represents a key issue in microwave circuit design. This is especially true when the particular applications involved (e.g., satellite, military, consumer) do not allow or strongly discourage any kind of maintenance. As a matter of fact, in order to account for device degradation in circuit design, a suitable electron device model is needed which is able to predict the performance degradation as a function of the actual electrical regime involved in the device operation. Such a kind of model is not available in literature. In this paper, quantitative results are provided for device degradation indicators which correlate DC and RF stress experiments. These results can be considered an important step toward the definition of a nonlinear model accounting for device degradation. 相似文献
28.
In this study, delamination of a perfectly-adherent FRP reinforcement from a masonry pillar is investigated by means of a fully three-dimensional finite element model. It is shown that the width of the FRP reinforcement governs the propagation of damage through the brick bulk starting from the anchorage of the strip, and influences significantly the overall response in terms of peak strength, ductility and fracture energy. The resulting failure mechanisms are specified. A critical comparison with formulae provided by Italian design code is also provided, for which mechanically-based improvements are suggested, taking into account three-dimensional effects. 相似文献
29.
Biological tissue characterization by magnetic induction spectroscopy (MIS): requirements and limitations 总被引:4,自引:0,他引:4
Magnetic induction spectroscopy (MIS) aims at the contactless measurement of the passive electrical properties (PEP) sigma, epsilon, and mu of biological tissues via magnetic fields at multiple frequencies. Whereas previous publications focus on either the conductive or the magnetic aspect of inductive measurements, this article provides a synthesis of both concepts by discussing two different applications with the same measurement system: 1) monitoring of brain edema and 2) the estimation of hepatic iron stores in certain pathologies. We derived the equations to estimate the sensitivity of MIS as a function of the PEP of biological objects. The system requirements and possible systematic errors are analyzed for a MIS-channel using a planar gradiometer (PGRAD) as detector. We studied 4 important error sources: 1) moving conductors near the PGRAD; 2) thermal drifts of the PGRAD-parameters; 3) lateral displacements of the PGRAD; and 4) phase drifts in the receiver. All errors were compared with the desirable resolution. All errors affect the detected imaginary part (mainly related to sigma) of the measured complex field much less than the real part (mainly related to epsilon and mu). Hence, the presented technique renders possible the resolution of (patho-) physiological changes of the electrical conductivity when applying highly resolving hardware and elaborate signal processing. Changes of the magnetic permeability and permittivity in biological tissues are more complicated to deal with and may require chopping techniques, e.g., periodic movement of the object. 相似文献
30.
Cardenas Angelica Moreno Nakamura Pinto Miguel Kiyoshy Pietrosemoli Ermanno Zennaro Marco Rainone Marco Manzoni Pietro 《Mobile Networks and Applications》2020,25(3):961-968
Mobile Networks and Applications - In this paper we describe a low-cost and low-power consumption messaging system based on LoRa technology. More that one billion people worldwide cannot access... 相似文献