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71.
Saurabh Bhatia Rashita Makkar Tapan Behl Aayush Sehgal Sukhbir Singh Mahesh Rachamalla Vasudevan Mani Muhammad Shahid Iqbal Simona Gabriela Bungau 《Molecules (Basel, Switzerland)》2022,27(5)
Marine drugs are abundant in number, comprise of a diverse range of structures with corresponding mechanisms of action, and hold promise for the discovery of new and better treatment approaches for the management of several chronic diseases. There are huge reserves of natural marine biological compounds, as 70 percent of the Earth is covered with oceans, indicating a diversity of chemical entities on the planet. The marine ecosystems are a rich source of bioactive products and have been explored for lead drug molecules that have proven to be novel therapeutic targets. Over the last 70 years, many structurally diverse drug products and their secondary metabolites have been isolated from marine sources. The drugs obtained from marine sources have displayed an exceptional potential in the management of a wide array of diseases, ranging from acute to chronic conditions. A beneficial role of marine drugs in human health has been recently proposed. The current review highlights various marine drugs and their compounds and role in the management of chronic diseases such as cancer, diabetes, neurodegenerative diseases, and cardiovascular disorders, which has led to the development of new drug treatment approaches. 相似文献
72.
Gabriela Pin-Zrate Fernanda Reyes-Riquelme Ma Beatriz Snchez-Monroy Mnica Velasco-Torrez Mariano Martínez-Vzquez Christian Adrian Crdenas-Monroy Beatriz Hernandez-Tllez Katia Jarquín-Yez Miguel ngel Herrera-Enríquez Andrs Eliú Castell-Rodríguez 《Molecules (Basel, Switzerland)》2022,27(4)
Dendritic cells are antigen-presenting cells, which identify and process pathogens to subsequently activate specific T lymphocytes. To regulate the immune responses, DCs have to mature by the recognition of TLR ligands, TNFα or IFNγ. These ligands have been used as adjuvants to activate DCs in situ or in vitro, with toxic effects. It has been shown that some molecules affect the immune system, e.g., Masticadienonic acid (MDA) and 3α-hydroxy masticadienoic acid (3α-OH MDA) triterpenes naturally occurring in several medicinal plants, since they activate the nitric oxide synthase in macrophages and induce T lymphocyte proliferation. The DCs maturation induced by MDA or 3a-OH MDA was determined by incubating these cells with MDA or 3α-OH MDA, and their phenotype was afterwards analyzed. The results showed that only 3α-OH MDA was able to induce DCs maturation. When mice with melanoma were inoculated with DCs/3α-OH MDA, a decreased tumor growth rate was observed along with an extended cell death area within tumors compared to mice treated with DCs incubated with MDA. In conclusion, it is proposed that 3α-OH MDA may be an immunostimulant molecule. Conversely, it is proposed that MDA may be a molecule with anti-inflammatory properties. 相似文献
73.
74.
Saida Sissi Silvia Di Giacomo Claudio Ferrante Paola Angelini Alberto Macone Anna Maria Giusti Chiara Toniolo Annabella Vitalone Aghraz Abdellah Mustapha Larhsini Luigi Menghini Mohammed Markouk Gabriela Mazzanti Antonella Di Sotto 《Molecules (Basel, Switzerland)》2022,27(3)
In the present study, the phytochemical composition and bioactivities of A. maroccanus (AM) and A. radiatus (AR), two ecotypes collected in the Demnate road and Essaouira regions, respectively, were studied to highlight a pharmacological interest and to enable possible pharmaceutical development. To this end, methanolic and ethyl acetate extracts were prepared for each ecotype by fractionation; next, their phytochemical composition was evaluated by spectrophotometric and chromatographic analysis. Moreover, in line with the available evidence for Anacyclus spp. and their traditional use, a screening of bioactivities, including antioxidant, hypoglycemic, antiglycative, chelating, and antibacterial activities, was performed. The extracts were characterized by high amounts of polyphenols, tannins, and flavonoids, especially in the methanolic extracts; these samples were also enriched in carotenoids despite a lower chlorophyll content. Chlorogenic acid and rutin were the major identified compounds. The extracts also showed interesting hypoglycemic, antiglycative, and antibacterial properties, although with differences in efficacy and potency. Present results provide more scientific basis to the ethnopharmacological uses of Anacyclus spp. and suggest a further interest in AM and AR ecotypes as natural sources of bioactive compounds and/or phytocomplexes for possible pharmaceutical and nutraceutical developments. 相似文献
75.
Gabriela HuelgasLynne K. LaRochelle Lucrecia RivasYekaterina Luchinina Rubén A. ToscanoPatrick J. Carroll Patrick J. WalshCecilia Anaya de Parrodi 《Tetrahedron》2011,67(24):4467-4474
The catalytic asymmetric addition of alkyl groups to ketones has received considerable attention. Outlined herein is the synthesis of two new ligands based on the C2-symmetric 11,12-diamino-9,10-dihydro-9,10-ethanoanthracene. The scope of the new ligands has been evaluated in the catalytic asymmetric addition of diethylzinc to a variety of ketones. Enantioselectivities as high as 99% have been achieved. The structures of two of these ligands have been determined by X-ray crystallography and are compared with related structures. Additionally, the structure of a titanium complex bound to a bis(sulfonamide) diol ligand is reported. 相似文献
76.
Kinga Nawalany Aleksandra Rusin Mariusz Kpczyski Alexei Mikhailov Gabriela Kramer-Marek Mirosaw
nietura Jan Potowicz Zdzisaw Krawczyk Maria Nowakowska 《Journal of photochemistry and photobiology. B, Biology》2009,97(1):8-17
Two photosensitizing systems: (1) tetrakis(4-hydroxyphenyl)porphyrin (p-THPP) encapsulated in sterically stabilized liposomes (SSL) and (2) p-THPP functionalized by covalent attachment of poly(ethylene glycol) (p-THPP–PEG2000) were studied in vitro. The dark and photo cytotoxicity of these systems were evaluated on two cell lines: HCT 116, a human colorectal carcinoma cell line, and DU 145, a prostate cancer cell line and compared with these determined for free p-THPP. It was demonstrated that both encapsulation in liposomes as well as attachment of PEG chain result in pronounced reduction of the dark cytotoxicity of the parent porphyrin. The liposomal formulation showed higher than p-THPP–PEG2000 photocytotoxicity towards both cell lines used in the studies. 相似文献
77.
Gabriela Molar-Velázquez Francisco J. Renero-Carrillo Wilfrido Calleja-Arriaga 《Optik》2010,121(9):843-846
A two-dimensional optical micro-scanner, which main components are two mobile flat and a concave micro-mirrors, is designed such that, all optical components can be fabricated on the same substratum. The optical parameters, which physical dimensions are between 50 and 500 μm, are obtained within the geometrical optics. The optical performance is evaluated by means of the MTF and Rayleigh resolution criteria, given 80% of modulation for a frequency of 8 cycles/mm with a Gaussian source, the resolution limit is 30 μm. 相似文献
78.
Eveline De Robertis Gabriela F. Moreira Raigna A. Silva Carlos A. Achete 《Journal of Thermal Analysis and Calorimetry》2011,106(2):347-354
Quality control of fuel-related properties of biodiesel, such as thermal stability, is needed to obtain consistent engine
performance by fuel users, since biodiesel is susceptible to auto-oxidation when exposed to air, light, and temperature during
storage. In this work two pure standard reference materials of biodiesels produced from soy oil and animal feedstocks were
studied. Differential scanning calorimetry and thermogravimetry measurements were performed and the analysis of the results
revealed small temperature variations in the thermal events among the two standards, these differences are due mainly to their
chemical composition, been highly influenced by the amounts of unsaturated esters. 相似文献
79.
80.
From superhydrophobic‐ to superhydrophilic‐patterned poly(vinylidene fluoride‐co‐chlorotrifluoroethylene) architectures as a novel platform for biotechnological applications 下载免费PDF全文
Vanessa F. Cardoso Ana R. Machado Vânia C. Pinto Paulo J. Sousa Gabriela Botelho Graça Minas Senentxu Lanceros‐Méndez 《Journal of Polymer Science.Polymer Physics》2016,54(18):1802-1810
The manufacture of three‐dimensional patterned electroactive poly(vinylidene fluoride‐co‐chlorotrifluoroethylene) microstructures with tailored architecture, morphology, and wettability is presented. The patterned microstructures are fabricated using a simple, effective, low cost, and reproducible technique based on microfluidic technology. These novel structures can represent innovative platforms for advanced strategies in a wide range of biotechnological applications, including tissue engineering, drug delivery, microfluidic, and sensors and actuators devices. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 1802–1810 相似文献