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931.
Sara Silva Cludia Alves Diana Duarte Ana Costa Bruno Sarmento Antnio J. Almeida Paula Gomes Nuno Vale 《International journal of molecular sciences》2021,22(1)
Drug repurposing and drug combination are two strategies that have been widely used to overcome the traditional development of new anticancer drugs. Several FDA-approved drugs for other indications have been tested and have demonstrated beneficial anticancer effects. In this connection, our research group recently reported that Tacrine, used to treat Alzheimer’s Disease, inhibits the growth of breast cancer MCF-7 cells both alone and in combination with a reference drug. In this view, we have now coupled Tacrine with the model amphipathic cell-penetrating peptide (CPP) MAP, to ascertain whether coupling of the CPP might enhance the drug’s antiproliferative properties. To this end, we synthesized MAP through solid-phase peptide synthesis, coupled it with Tacrine, and made a comparative evaluation of the parent drug, peptide, and the conjugate regarding their permeability across the blood-brain barrier (BBB), ability to inhibit acetylcholinesterase (AChE) in vitro, and antiproliferative activity on cancer cells. Both MAP and its Tacrine conjugate were highly toxic to MCF-7 and SH-SY5Y cells. In turn, BBB-permeability studies were inconclusive, and conjugation to the CPP led to a considerable loss of Tacrine function as an AChE inhibitor. Nonetheless, this work reinforces the potential of repurposing Tacrine for cancer and enhances the antiproliferative activity of this drug through its conjugation to a CPP. 相似文献
932.
Gregory A. Campbell Ross Taylor Mark D. Wetzel Shaji Chempath Sirisha Bomma Samuel St. John Diana Hunt David L. Powers 《American Institute of Chemical Engineers》2022,68(4):e17557
A recently published approach for modeling the cross flow in an extruder channel using a new solution to the biharmonic equation is utilized in a study of chaotic mixing in a free-helix single-screw extruder. This novel extruder was designed and constructed with the screw flight, also referred to as the helix, detached from the screw core. The flight-helix had straight sides that more closely emulated rectangular channel theory than the nominal sloped sides of a conventional single screw channel. Each of the screw elements could be rotated independently to obtain chaotic motion in the screw channel. Using the new extruder, experimental evidence for the increased mixing of a dye, for both a Dirac and droplet input, with a chaotic flow field relative to the traditional residence time distribution is presented. These experimental results are compared using the new biharmonic equation-based model. Comparing the experimental chaotic mixing with theoretical calculations was facilitated by a recently published technique for accurately placing the dye in the extruder channel. Because of the ability to periodically rotate only the flight/helix, the chaotic mixing results are minimally confounded by the existence of Moffatt eddies. 相似文献
933.
Caroline de Souza Pereira Helenita Costa Quadros Dr. Diogo Rodrigo Magalhaes Moreira Dr. William Castro Romulo Ivisson Santos De Deus Da Silva Dr. Milena Botelho Pereira Soares Dr. Diana Fontinha Dr. Miguel Prudêncio Vinicius Schmitz Prof. Hélio F. Dos Santos Mathieu Gendrot Isabelle Fonta Joel Mosnier Dr. Bruno Pradines Prof. Maribel Navarro 《ChemMedChem》2021,16(4):662-678
Plasmodium parasites kill 435 000 people around the world every year due to unavailable vaccines, a limited arsenal of antimalarial drugs, delayed treatment, and the reduced clinical effectiveness of current practices caused by drug resistance. Therefore, there is an urgent need to discover and develop new antiplasmodial candidates. In this work, we present a novel strategy to develop a multitarget metallic hybrid antimalarial agent with possible dual efficacy in both sexual and asexual erythrocytic stages. A hybrid of antimalarial drugs (chloroquine and primaquine) linked by gold(I) was synthesized and characterized by spectroscopic and analytical techniques. The CQPQ-gold(I) hybrid molecule affects essential parasite targets, it inhibits β-hematin formation and interacts moderately with the DNA minor groove. Its interaction with PfTrxR was also examined in computational modeling studies. The CQPQ-gold(I) hybrid displayed an excellent in vitro antimalarial activity against the blood-stage of Plasmodium falciparum and liver-stage of Plasmodium berghei and efficacy in vivo against P. berghei, thereby demonstrating its multiple-stage antiplasmodial activity. This metallic hybrid is a promising chemotherapeutic agent that could act in the treatment, prevention, and transmission of malaria. 相似文献
934.
Diana Rocha-Mendoza Erica Kosmerl Abigail Krentz Lin Zhang Shivani Badiger Gonzalo Miyagusuku-Cruzado Alba Mayta-Apaza Monica Giusti Rafael Jiménez-Flores Israel García-Cano 《Journal of dairy science》2021,104(2):1262-1275
In recent years, acid whey production has increased due to a growing demand for Greek yogurt and acid-coagulated cheeses. Acid whey is a dairy by-product for which the industry has long struggled to find a sustainable application. Bulk amounts of acid whey associated with the dairy industry have led to increasing research on ways to valorize it. Industry players are finding ways to use acid whey on-site with ultrafiltration techniques and biodigesters, to reduce transportation costs and provide energy for the facility. Academia has sought to further investigate practical uses and benefits of this by-product. Although modern research has shown many other possible applications for acid whey, no comprehensive review yet exists about its composition, utilization, and health benefits. In this review, the industrial trends, the applications and uses, and the potential health benefits associated with the consumption of acid whey are discussed. The proximal composition of acid whey is discussed in depth. In addition, the potential applications of acid whey, such as its use as a starting material in the production of fermented beverages, as growth medium for cultivation of lactic acid bacteria in replacement of commercial media, and as a substrate for the isolation of lactose and minerals, are reviewed. Finally, the potential health benefits of the major protein constituents of acid whey, bioactive phospholipids, and organic acids such as lactic acid are described. Acid whey has promising applications related to potential health benefits, ranging from antibacterial effects to cognitive development for babies to human gut health. 相似文献
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938.
Maynard Diana Lepori Benedetto Petrak Johann Song Xingyi Laredo Philippe 《Scientometrics》2020,125(2):1275-1290
Scientometrics - Understanding knowledge co-creation in key emerging areas of European research is critical for policy makers wishing to analyze impact and make strategic decisions. However, purely... 相似文献
939.
ABSTRACTThe lack of diversity in engineering and perpetuation of inequities through engineering designs have motivated the rise of new curricula centred on the integration of traditional technical content with social aspects of technology. However, the ‘revolutionizing’ of curricula has primarily been spearheaded by junior faculty, women and faculty of colour. This article uses an autoethnographic approach to explore the development of social justice-oriented curricula within engineering from the perspectives of junior women and faculty of colour. Drawing on feminist and critical race theory, we discuss how power dynamics within the school, university and engineering more broadly have shaped the development and teaching of justice-oriented engineering. Through the lens of our experiences, we show that, despite the support from some institutional allies and administrators, stereotypes, hegemonic norms and microaggressions can undermine efforts for social and structural change in engineering education, even as such changes are supported and promoted by the institution. 相似文献
940.
Cosmin M. Cotrut Alina Vladescu Mihaela Dinu Diana M. Vranceanu 《Ceramics International》2018,44(1):669-677
Surface functionalization of pure titanium (cp-Ti) with hydroxyapatite (HAp) was successfully achieved by means of electrochemical deposition (ED) in a solution containing calcium nitrate and ammonium dihydrogen phosphate. The aim of this study is to evaluate the influence of the deposition temperature on the elemental and phase composition, chemical bonds, morphology, and in vitro electrochemical behaviour in biological simulated media (simulated body fluid - SBF). The roughness and wettability of the developed coatings are also investigated. By increasing the deposition temperature from 50 °C to 75 °C, the HAp coatings present a well-crystalized structure, denser and a nobler behaviour in terms of electrochemical behaviour in SBF at 37 °C. Also, by increasing the deposition temperature from 50 °C to 75 °C, the contact angle has decreased from 76.1° to 27.4°, exhibiting a highly hydrophilic surface. Taking into consideration all the obtained data, electrodeposition of HAp at 75 °C was found preferable when compared to 50 °C. The characteristics of the HAp coatings can be easily adjusted by optimizing the electrochemical deposition parameters and/or controlling specific features like pH, temperature, or ionic concentration of electrolyte, etc. 相似文献