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991.
L. R. Ribeiro E. Passos C. Furtado J. R. Nascimento 《The European Physical Journal C - Particles and Fields》2008,56(4):597-606
We investigate the analog of Landau quantization, for a neutral polarized particle in the presence of homogeneous electric
and magnetic external fields, in the context of non-commutative quantum mechanics. This particle, possessing electric and
magnetic dipole moments, interacts with the fields via the Aharonov–Casher and He–McKellar–Wilkens effects. For this model
we obtain the Landau energy spectrum and the radial eigenfunctions of the non-commutative space coordinates and non-commutative
phase space coordinates. Also we show that the case of non-commutative phase space can be treated as a special case of the
usual non-commutative space coordinates. 相似文献
992.
Ana T. P. C. Gomes M. Graa P. M. S. Neves Rosa Fernandes Carlos F. Ribeiro Jos A. S. Cavaleiro Nuno M. M. Moura 《Molecules (Basel, Switzerland)》2021,26(17)
In this study, we report the preparation of new mono-charged benzoporphyrin complexes by reaction of the appropriate neutral benzoporphyrin with (2,2′-bipyridine)dichloroplatinum(II) and of the analogs’ derivatives synthesized through alkylation of the neutral scaffold with iodomethane. All derivatives were incorporated into polyvinylpyrrolidone (PVP) micelles. The ability of the resultant formulations to generate reactive oxygen species was evaluated, mainly the singlet oxygen formation. Then, the capability of the PVP formulations to act as photosensitizers against bladder cancer cells was assessed. Some of the studied formulations were the most active photosensitizers causing a decrease in HT-1376 cells’ viability. This creates an avenue to further studies related to bladder cancer cells. 相似文献
993.
Larissa C. Ghirro Stephany Rezende Andreia S. Ribeiro Nuno Rodrigues Mrcio Carocho Jos Alberto Pereira Lillian Barros Bogdan Demczuk Jr. Maria-Filomena Barreiro Arantzazu Santamaria-Echart 《Molecules (Basel, Switzerland)》2022,27(4)
Pickering emulsions, which are emulsions stabilized by colloidal particles, are being increasingly positioned as novel strategies to develop innovative food product solutions. In this context, the present work aims to develop Pickering emulsions stabilized by natural-based curcumin-loaded particles produced by the solid dispersion technique as promising mayonnaise-like food sauce alternatives. Two particle formulations (KC1 and KC2) were produced using k-carrageenan as the matrix material and different curcumin contents, then employed in the preparation of three Pickering emulsion formulations comprising different oil fractions (φ) and particle concentrations (KC1 φ 0.4 (4.7%), KC2 φ 0.4 (4.7%) and KC2 φ 0.6 (4.0%)). The creaming index tests accompanied by the optical microscopy analysis evidenced the good stability of the developed products for the tested period of 28 days. The final products were tested concerning color attributes, pH, oxidative stability, textural, and nutritional composition, and compared with two commercial mayonnaises (traditional and light products). Overall, the produced emulsions were characterized by a bright yellow color (an appealing attribute for consumers), an acidic pH (similar to mayonnaise), and a considerably improved oxidative stability, implying a foreseeable longer shelf life. The sauce KC1 φ 0.4 (4.7%) showed a similar texture to the light commercial mayonnaise, being a promising alternative to conventional sauces, holding a low-fat content and potentially added benefits due to the curcumin and virgin olive oil intrinsic properties. 相似文献
994.
Fabiola Vieira de Carvalho Ligia Nunes de Morais Ribeiro Ludmilla David de Moura Gustavo Henrique Rodrigues da Silva Hery Mitsutake Talita Cesarim Mendona Gabriela Geronimo Marcia Cristina Breitkreitz Eneida de Paula 《Molecules (Basel, Switzerland)》2022,27(24)
Breast cancer is the neoplasia of highest incidence in women worldwide. Docetaxel (DTX), a taxoid used to treat breast cancer, is a BCS-class-IV compound (low oral bioavailability, solubility and intestinal permeability). Nanotechnological strategies can improve chemotherapy effectiveness by promoting sustained release and reducing systemic toxicity. Nanostructured lipid carriers (NLC) encapsulate hydrophobic drugs in their blend-of-lipids matrix, and imperfections prevent drug expulsion during storage. This work describes the preparation, by design of experiments (23 factorial design) of a novel NLC formulation containing copaiba oil (CO) as a functional excipient. The optimized formulation (NLCDTX) showed approximately 100% DTX encapsulation efficiency and was characterized by different techniques (DLS, NTA, TEM/FE-SEM, DSC and XRD) and was stable for 12 months of storage, at 25 °C. Incorporation into the NLC prolonged drug release for 54 h, compared to commercial DTX (10 h). In vitro cytotoxicity tests revealed the antiproliferative effect of CO and NLCDTX, by reducing the cell viability of breast cancer (4T1/MCF-7) and healthy (NIH-3T3) cells more than commercial DTX. NLCDTX thus emerges as a promising drug delivery system of remarkable anticancer effect, (strengthened by CO) and sustained release that, in clinics, may decrease systemic toxicity at lower DTX doses. 相似文献
995.
Rodolfo Santos Duarte Elisa Ribeiro Miranda Antunes Alexandra Christine Helena Frankland Sawaya 《Molecules (Basel, Switzerland)》2022,27(17)
Due to the widespread use of Maytenus ilicifolia leaves in the treatment of gastric ulcers, herbal medicines derived from such species are distributed by the national health system in Brazil. A related species, Maytenus aquifolium, is also used for the same disorders, and both are popularly known as Espinheira-santa. Due to their popular use, the quality and efficiency of the herbal medicines derived from these species is an important public health issue. The purpose of this study was to develop and test an analytical method that could quantify the content of catechin and epicatechin in dry Maytenus spp. leaves and simultaneously obtain their chemical profile to determine authenticity of the leaf samples. Ultra-high performance liquid chromatography coupled to mass spectrometry (UHPLC-MS) was used to quantify these isomers, in the selected ion monitoring (SIM) mode, while simultaneously analyzing the extract in full-scan mode. This approach was successfully applied to the analysis of commercial and authentic samples of Maytenus spp. Fewer than half the samples presented the minimum epicatechin content of 2.8 mg per g of dry leaf mass, as specified in the 6th Brazilian Pharmacopoeia (2019) for M. ilicifolia. Furthermore, by using untargeted metabolomics, it was observed that the chemical profile of most the samples was not compatible with M. ilicifolia leaves, indicating the need for stricter quality control of this material. The method described herein could be used for this control; moreover, its concept could be adapted and used for an ample variety of medicinal plant products. 相似文献
996.
Noemi Oliveira Monteiro Theresa de Moura Monteiro Thalya Soares R. Nogueira Jacqueline Rodrigues Cesar Lara Pessanha S. Nascimento Karoline Azerêdo Campelo Graziela Rangel Silveira Fernanda Antunes Daniela Barros de Oliveira Almir Ribeiro de Carvalho Junior Raimundo Braz-Filho Ivo Jos Curcino Vieira 《Molecules (Basel, Switzerland)》2022,27(20)
The alkaloid Aspidocarpine was isolated from the bark of Aspidosperma desmanthum. Its structure was elucidated by the spectral data of 1H and 13C-NMR (1D and 2D) and high-resolution mass spectrometry (HRESIMS). The antihypertensive activity was investigated by intravenous infusion in Wistar rats. This alkaloid significantly reduced (p < 0.05) the systolic, median, and diastolic blood pressures of rodents, without causing motor incoordination and imbalance in the rotarod test. The results indicate that the alkaloid Aspidocarpine exerts its antihypertensive activity without causing sedation or the impairment of motor functions. 相似文献
997.
Cláudia B. A. Medeiros Iasmim Lopes de Lima Thiago Barbosa Cahú Bruna R. Muniz Maria Helena M. L. Ribeiro Érico Higino de Carvalho Marcos Nogueira Eberlin Marcelo J. B. Miranda Ranilson de Souza Bezerra Roberto Afonso da Silva José Luiz de Lima Filho 《Journal of mass spectrometry : JMS》2024,59(1):e4988
Full-thickness cutaneous trauma, due to the lack of dermis, leads to difficulty in epithelialization by keratinocytes, developing a fibrotic scar, with less elasticity than the original skin, which may have disorders in predisposed individuals, resulting in hypertrophic scar and keloids. Biomedical materials have excellent characteristics, such as good biocompatibility and low immunogenicity, which can temporarily replace traditional materials used as primary dressings. In this work, we developed two dermal matrices based on Nile tilapia collagen, with (M_GAG) and without (M) glycosaminoglycans, using a sugarcane polymer membrane as a matrix support. To assess the molecular mechanisms driving wound healing, we performed qualitative proteomic analysis on the wound bed in an in vivo study involving immunocompetent murine models at 14 and 21 days post-full-thickness skin injury. Gene Ontology and Pathway analysis revealed that both skins were markedly represented by modulation of the immune system, emphasizing controlling the acute inflammation response at 14 and 21 days post-injury. Furthermore, both groups showed significant enrichment of pathways related to RNA and protein metabolism, suggesting an increase in protein synthesis required for tissue repair and proper wound closure. Other pathways, such as keratinization and vitamin D3 metabolism, were also enriched in the groups treated with M matrix. Finally, both matrices improved wound healing in a full post-thick skin lesion. However, our preliminary molecular data reveals that the collagen-mediated healing matrix lacking glycosaminoglycan (M) exhibited a phenotype more favorable to tissue repair, making it more suitable for use before skin grafts. 相似文献
998.
Madeleine Ramstedt Isabel A. C. Ribeiro Helena Bujdakova Filipe J. M. Mergulho Luisa Jordao Peter Thomsen Martin Alm Mette Burmlle Todorka Vladkova Fusun Can Meital Reches Martijn Riool Alexandre Barros Rui L. Reis Emilio Meaurio Judith Kikhney Annette Moter Sebastian A. J. Zaat Jelmer Sjollema 《Macromolecular bioscience》2019,19(5)
In Europe, the mean incidence of urinary tract infections in intensive care units is 1.1 per 1000 patient‐days. Of these cases, catheter‐associated urinary tract infections (CAUTI) account for 98%. In total, CAUTI in hospitals is estimated to give additional health‐care costs of £1–2.5 billion in the United Kingdom alone. This is in sharp contrast to the low cost of urinary catheters and emphasizes the need for innovative products that reduce the incidence rate of CAUTI. Ureteral stents and other urinary‐tract devices suffer similar problems. Antimicrobial strategies are being developed, however, the evaluation of their efficacy is very challenging. This review aims to provide considerations and recommendations covering all relevant aspects of antimicrobial material testing, including surface characterization, biocompatibility, cytotoxicity, in vitro and in vivo tests, microbial strain selection, and hydrodynamic conditions, all in the perspective of complying to the complex pathology of device‐associated urinary tract infection. The recommendations should be on the basis of standard assays to be developed which would enable comparisons of results obtained in different research labs both in industry and in academia, as well as provide industry and academia with tools to assess the antimicrobial properties for urinary tract devices in a reliable way. 相似文献
999.
Silva Ana L. R. Lima Ana C. M. O. Ribeiro da Silva Maria D. M. C. 《Journal of Thermal Analysis and Calorimetry》2018,134(2):1267-1276
Journal of Thermal Analysis and Calorimetry - The energetic study of 6-methyl-1-indanone, 6-methoxy-1-indanone and 5,6-dimethoxy-1-indanone has been developed using calorimetric techniques and a... 相似文献
1000.
Volodymyr Gvozdetskyi Michael P. Hanrahan Raquel A. Ribeiro Tae-Hoon Kim Lin Zhou Aaron J. Rossini Paul C. Canfield Julia V. Zaikina 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(16):4123-4135
Ternary lithium nickel borides LiNi3B1.8 and Li2.8Ni16B8 have been synthesized by using reactive LiH as a precursor. This synthetic route allows better mixing of the precursor powders, thus facilitating rapid preparation of the alkali-metal-containing ternary borides. This method is suitable for “fast screening” of multicomponent systems comprised of elements with drastically different reactivities. The crystal structures of the compounds LiNi3B1.8 and Li2.8Ni16B8 have been re-investigated by a combination of single-crystal X-ray/synchrotron powder diffraction, solid-state 7Li and 11B NMR spectroscopies, and scanning transmission electron microscopy. This has allowed the determination of fine structural details, including the split position of Ni sites and the ordering of B vacancies. Field-dependent and temperature-dependent magnetization measurements are consistent with spin-glass behavior for both samples. 相似文献