排序方式: 共有31条查询结果,搜索用时 11 毫秒
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Bassam Felipe Mogharbel Marco Andr Cardoso Ana Carolina Irioda Priscila Elias Ferreira Stricker Robson Camilotti Slompo Julia Maurer Appel Nathalia Barth de Oliveira Maiara Carolina Perussolo Claudia Sayuri Saaki Nadia Nascimento da Rosa Dilcele Silva Moreira Dziedzic Christophe Travelet Sami Halila Redouane Borsali Katherine Athayde Teixeira de Carvalho 《Molecules (Basel, Switzerland)》2022,27(9)
Background: Parkinson’s disease (PD) is the second most common age-related neurodegenerative disorder. Levodopa (L-DOPA) remains the gold-standard drug available for treating PD. Curcumin has many pharmacological activities, including antioxidant, anti-inflammatory, antimicrobial, anti-amyloid, and antitumor properties. Copolymers composed of Poly (ethylene oxide) (PEO) and biodegradable polyesters such as Poly (ε-caprolactone) (PCL) can self-assemble into nanoparticles (NPs). This study describes the development of NH2–PEO–PCL diblock copolymer positively charged and modified by adding glutathione (GSH) on the outer surface, resulting in a synergistic delivery of L-DOPA curcumin that would be able to pass the blood–brain barrier. Methods: The NH2–PEO–PCL NPs suspensions were prepared by using a nanoprecipitation and solvent displacement method and coated with GSH. NPs were submitted to characterization assays. In order to ensure the bioavailability, Vero and PC12 cells were treated with various concentrations of the loaded and unloaded NPs to observe cytotoxicity. Results: NPs have successfully loaded L-DOPA and curcumin and were stable after freeze-drying, indicating advancing into in vitro toxicity testing. Vero and PC12 cells that were treated up to 72 h with various concentrations of L-DOPA and curcumin-loaded NP maintained high viability percentage, indicating that the NPs are biocompatible. Conclusions: NPs consisting of NH2–PEO–PCL were characterized as potential formulations for brain delivery of L-DOPA and curcumin. The results also indicate that the developed biodegradable nanomicelles that were blood compatible presented low cytotoxicity. 相似文献
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Sofia Nascimento dos Santos Sara Rhaissa Rezende dos Reis Suyene Rocha Pinto Cristal Cerqueira-Coutinho Fiammetta Nigro Thereza Christina Barja-Fidalgo Nathalia Martins Alexandre Pinheiro Heitor Affonso Paula Neto Ralph Santos-Oliveira 《Journal of nanoparticle research》2017,19(10):345
Despite advancements in treatment of infectious diseases, opportunistic pathogens continue to pose a worldwide threat. Identifying a source of infection/inflammation is often challenging which highlights the need of improved diagnostic agents. Using a model of local S. aureus infection, here we evaluated the potential of betamethasone or dexamethasone loaded in poly (lactic acid) nanoparticles and radiolabeled with 99mTc to detect an infection/inflammation site in vivo. A betamethasone and dexamethasone nanoparticles (NPs) with 200 and 220 nm in size, respectively, were created with a 98% 99mTc radiolabeling efficiency. When injected in infected mice, betamethasone NPs presented a higher accumulation in the infected hind paw in comparison with dexamethasone NPs. Our results suggest that this nanosystem may be a valid nanoradiopharmaceutical for the detection of inflammation/infection foci in vivo. 相似文献
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Karina Penedo Carvalho Nathalia Balthazar Martins Ana Rosa Lopes Pereira Ribeiro Taliria Silva Lopes Rodrigo Caciano de Sena Pascal Sommer José Mauro Granjeiro 《Journal of nanoparticle research》2016,18(8):244
Nanoparticles agglomerate when in contact with biological solutions, depending on the solutions’ nature. The agglomeration state will directly influence cellular response, since free nanoparticles are prone to interact with cells and get absorbed into them. In sunscreens, titanium dioxide nanoparticles (TiO2-NPs) form mainly aggregates between 30 and 150 nm. Until now, no toxicological study with skin cells has reached this range of size distribution. Therefore, in order to reliably evaluate their safety, it is essential to prepare suspensions with reproducibility, irrespective of the biological solution used, representing the above particle size distribution range of NPs (30–150 nm) found on sunscreens. Thus, the aim of this study was to develop a unique protocol of TiO2 dispersion, combining these features after dilution in different skin cell culture media, for in vitro tests. This new protocol was based on physicochemical characteristics of TiO2, which led to the choice of the optimal pH condition for ultrasonication. The next step consisted of stabilization of protein capping with acidified bovine serum albumin, followed by an adjustment of pH to 7.0. At each step, the solutions were analyzed by dynamic light scattering and transmission electron microscopy. The final concentration of NPs was determined by inductively coupled plasma-optical emission spectroscopy. Finally, when diluted in dulbecco’s modified eagle medium, melanocytes growth medium, or keratinocytes growth medium, TiO2–NPs displayed a highly reproducible size distribution, within the desired size range and without significant differences among the media. Together, these results demonstrate the consistency achieved by this new methodology and its suitability for in vitro tests involving skin cell cultures. 相似文献
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Zusammenfassung Zur Bestimmung des Selens in organischen Substanzen bewährt sich die jodometrische Bestimmung der selenigen Säure. Die Verbrennung der Probe kann entweder über Quarzwolle im Sauerstoffstrom oder im Schöniger-Kolben durchgeführt werden.
Summary The iodometric determination of selenious acid is excellent for determining selenium in organic substances. The combustion of the sample can be conducted either over quartz wool in a stream of oxygen or in theSchöniger flask.
Résumé Pour doser le sélénium dans les substances organiques la méthode iodométrique de l'acide sélénieux a fait ses preuves. On peut faire la calcination de l'essai soit sur laine de quartz dans un courant d'oxygène, soit dans une fiole deSchöniger相似文献
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Renata Jardim Etchart Raoní S. Rambo Bruno Lopes Abbadi Nathalia Sperotto Christiano Ev Neves Fernanda Fries Silva Maiele Dornelles Lovaine Duarte Fernanda Souza Macchi Marcia Alberton Perell Rogrio Vescia Lourega Cristiano Valim Bizarro Luiz Augusto Basso Pablo Machado 《Molecules (Basel, Switzerland)》2021,26(17)
Tuberculosis has been described as a global health crisis since the 1990s, with an estimated 1.4 million deaths in the last year. Herein, a series of 20 1H-indoles were synthesized and evaluated as in vitro inhibitors of Mycobacterium tuberculosis (Mtb) growth. Furthermore, the top hit compounds were active against multidrug-resistant strains, without cross-resistance with first-line drugs. Exposing HepG2 and Vero cells to the molecules for 72 h showed that one of the evaluated structures was devoid of apparent toxicity. In addition, this 3-phenyl-1H-indole showed no genotoxicity signals. Finally, time-kill and pharmacodynamic model analyses demonstrated that this compound has bactericidal activity at concentrations close to the Minimum Inhibitory Concentration, coupled with a strong time-dependent behavior. To the best of our knowledge, this study describes the activity of 3-phenyl-1H-indole against Mtb for the first time. 相似文献
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Salvador MJ de Lourenço CC Andreazza NL Pascoal AC Stefanello ME 《Natural product communications》2011,6(7):977-982
Antioxidant compounds can be useful to prevent several degenerative diseases or as preservative in food and toiletries. Species of the Myrtaceae family are able to accumulate phenolic substances and those are closely related to the antioxidant activity due to their capacity to scavenge free radicals, protect against lipid peroxidation and quench reactive oxygen species. These facts prompted us to investigate the antioxidant capacity of the ethanolic extracts of the leaves of four Myrtaceae plants collected of the south of Brazil: Eugenia chlorophylla O. Berg., Eugenia pyriformis Cambess, Myrcia laruotteana Cambess and Myrcia obtecta (Berg) Kiacrsk. The antioxidant potential was performed using the DPPH (a single electron transfer reaction based assay) and ORAC (Oxygen Radical Absorbance Capacity, a hydrogen atom transfer reaction based assay) assays. Moreover, the total soluble phenolic content was also measured using the Folin-Ciocalteu reagent. A preliminary evaluation of the ethanolic extracts of these Myrtaceae plants revealed high levels of phenolic compounds (343.7-429.3 mg GAE) as well as high antioxidant activity according to both methods (1338 a 3785 micromol of TE/g of extract in ORAC and SC50 in the range of 1.70 and 33.7 microg/mL in the DPPH). The highest antioxidant activity obtained by DPPH assay was exhibited by ethanol extract of the leaves of E. pyriformis (1.70 microg/mL), followed by extracts of M. laruotteana (3.38 microg/mL) and M. obtecta (6.66 microg/mL). In comparison with controls, in the DPPH assay, the extract of E. pyriformis was more active than trolox (SC50 = 2.55 microg/mL), while the extracts of M. laruotteana and M. obtecta were more actives than quercetin (SC50 = 7.80 microg/mL). In the ORAC assay, all species also show good antioxidant capacity (>1000 micromol of TE/g). Initial HPLC-UV/DAD and ESI-MS confirmed the presence of phenolic acids constituents in the ethanol extracts. The results indicate the presence of compounds possessing promising antioxidant/free-radical scavenging activity in the analyzed extracts of Myrcia and Eugenia plants of the south of Brazil. 相似文献
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Fabiana Fuentes-León Andressa Peres de Oliveira Nathalia Quintero-Ruiz Veridiana Munford Gustavo Satoru Kajitani Antônio Coimbra Brum André Passaglia Schuch Pio Colepicolo Angel Sánchez-Lamar Carlos Frederico Martins Menck 《Photochemistry and photobiology》2020,96(6):1215-1220
Sunlight ultraviolet (UV) radiation constitutes an important environmental genotoxic agent that organisms are exposed to, as it can damage DNA directly, generating pyrimidine dimers, and indirectly, generating oxidized bases and single-strand breaks (SSBs). These lesions can lead to mutations, triggering skin and eye disorders, including carcinogenesis and photoaging. Stratospheric ozone layer depletion, particularly in the Antarctic continent, predicts an uncertain scenario of UV incidence on the Earth in the next decades. This research evaluates the DNA damage caused by environmental exposure to late spring sunlight in the Antarctic Peninsula, where the ozone layer hole is more pronounced. These experiments were performed at the Brazilian Comandante Ferraz Antarctic Station, at King’s George Island, South Shetlands Islands. For comparison, tropical regions were also analyzed. Samples of plasmid DNA were exposed to sunlight. Cyclobutane pyrimidine dimers (CPDs), oxidized base damage and SSBs were detected using specific enzymes. In addition, an immunological approach was used to detect CPDs. The results reveal high levels of DNA damage induced by exposure under the Antarctic sunlight, inversely correlated with ozone layer thickness, confirming the high impact of ozone layer depletion on the DNA damaging action of sunlight in Antarctica. 相似文献
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Eduardo Rezende Graminho Ronivaldo Rodrigues da Silva Tatiana Pereira de Freitas Cabral Eliane Candiani Arantes Nathalia Gonsales da Rosa Luiz Juliano Debora Noma Okamoto Lilian Caroline Gonçalves de Oliveira Marcia Yuri Kondo Maria Aparecida Juliano Hamilton Cabral 《Applied biochemistry and biotechnology》2013,169(1):201-214
The purpose of this work was to purify a protease from Penicillium waksmanii and to determine its biochemical characteristics and specificity. The extracellular protease isolated that was produced by P. waksmanii is a serine protease that is essential for the reproduction and growth of the fungus. The protease isolated showed 32 kDa, and has optimal activity at pH 8.0 and 35 °C towards the substrate Abz-KLRSSKQ-EDDnp. The protease is active in the presence of CaCl2, KCl, and BaCl, and partially inhibited by CuCl2, CoCl2 and totally inhibited by AlCl3 and LiCl. In the presence of 1 M urea, the protease remains 50 % active. The activity of the protease increases 60 % when it is exposed to 0.4 % nonionic surfactant-Triton X-100 and loses 10 % activity in the presence of 0.4 % Tween-80. Using fluorescence resonance energy transfer analysis, the protease showed the most specificity for the peptide Abz-KIRSSKQ-EDDnp with k cat/K m of 10,666 mM?1?s?1, followed by the peptide Abz-GLRSSKQ-EDDnp with a k cat/K m of 7,500 mM?1?s?1. Basic and acidic side chain-containing amino acids performed best at subsite S1. Subsites S2, S3, S′ 2, and S′ 1, S′ 3 showed a preference for binding for amino acids with hydrophobic and basic amino acid side chain, respectively. High values of k cat/K m were observed for the subsites S2, S3, and S′ 2. The sequence of the N-terminus (ANVVQSNVPSWGLARLSSKKTGTTDYTYD) showed high similarity to the fungi Penicillium citrinum and Penicillium chrysogenum, with 89 % of identity at the amino acid level. 相似文献