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Curcumin (CUR) has been proved to be highly cytotoxic against different tumor cell lines. However, its poor solubility in aqueous medium and fast degradation in physiological pH are the common drawbacks preventing its efficient practical use. Herein, we report the development of original microspheres based on the biopolymer starch crosslinked with N,N-methylenebisacrylamide (MBA) to be applied as an efficient delivering system for CUR. The starch-based microspheres showed high loading efficiency even in loading solution with different CUR concentrations. In vitro release assays data showed that the CUR release is governed by anomalous transport (n = 0.73) and it is pH-dependent. Cytotoxicity assays showed that starch microspheres could improve the cytotoxicity of CUR toward Caco-2 and HCT-116 tumor cell lines up to 40 times than that found for pure CUR. This behavior was attributed to the slowly and sustained release of CUR from the microspheres.  相似文献   
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Genera of Eutheiini are reviewed and Eutheimorphus is removed from this tribe of ant‐like stone beetles (Scydmaeninae) and transferred to Cephenniini. A monogeneric Marcepaniini trib.n. is described to accommodate Marcepania gen.n. from Malaysia, with five species: M. semengohensis sp.n. (the type species of Marcepania), M. tuberculata sp.n. , M. seramaensis sp.n. , M. minutissima sp.n. and M. elongata sp.n. A phylogenetic analysis of all genera of Cephenniini, Eutheiini and Marcepaniini based on adult morphological characters resulted in recovering a well‐supported monophyletic clade Eutheiini + (Marcepaniini + Cephenniini) and these tribes are included in Cephenniitae stat.n. (Eutheiini and Cephenniini are therefore removed from Scydmaenitae). Only a weak support for monophyly of Eutheiini was found, but morphological characters allow for maintaining this presumably relic group as a separate tribe. Previously proposed monophyletic groups within Cephenniini were recovered as such, but after inclusion of Eutheimorphus, a sister taxon to the ‘Cephennomicrus group’, the latter lineage gained weak statistical support. The evolutionary history of Cephenniitae is discussed, with focus on known northern hemisphere fossils classified in Scydmaenitae and Hapsomelitae, but possibly closely allied to Cephenniitae. Establishing the supertribe Cephenniitae is the first step toward a profound reclassification of Scydmaeninae on a robust phylogenetic basis. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:B0E1B12D-9587-4C4F-A908-A12A0C424A8C .  相似文献   
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In this paper, we investigate the physical basis behind the molecular biochirality from the computation of a parity violation energy difference (PVED) in enantiomers of organic molecules (e.g., amino acids, which occur as levogyrous-type in nature), by considering the influence of fundamental interactions beyond the standard model of elementary particles and interactions. Particularly, we study the role of a 4-D Chern‑Simons theory at the origin of this PVED, the Carroll‑Field‑Jackiw electrodynamics, which violates both Lorentz and parity symmetries. Then, we consider terrestrial and Jovian scenarios where the influence of a modified (effective) magnetic field generated by the planets on the molecules is taken into account in the calculation of PVED. Besides this quantity, we also calculate the relative quantity excess of an enantiomer over the other in a thermal bath. Finally, we compare the obtained results with those ones from other models based on fundamental interactions.  相似文献   
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Neutrophils are leukocytes that are capable of eliminating both intra‐ and extracellular pathogens by mechanisms such as phagocytosis, degranulation, and release of neutrophil extracellular traps (NETs). Histoplasma capsulatum var. capsulatum (H. capsulatum) is a dimorphic fungus with a global distribution that causes histoplasmosis, a disease that is endemic in different geographic areas and is spreading worldwide. The release of NETs has been described as an important host defense mechanism against different fungi; however, there are no reports demonstrating that this process is implicated in neutrophil response to H. capsulatum infection. Therefore, the aim of this work is to investigate whether isolated human neutrophils release NETs in response to H. capsulatum and the potential mechanisms involved, as well as delineate the NETs antifungal activity. Using both confocal fluorescence and scanning electron microscopy techniques, we determined that NETs are released in vitro in response to H. capsulatum via an oxidative mechanism that is downstream of activation of the Syk and Src kinase pathways and is also dependent on CD18. NETs released in response to H. capsulatum yeasts involve the loss of neutrophil viability and are associated with elastase and citrullinated histones, however also can occur in a PAD4 histone citrullination independent pathway. This NETs also presented fungicidal activity against H. capsulatum yeasts. Our findings may contribute to the understanding of how neutrophils recognize and respond as immune effector cells to H. capsulatum, which may lead to better knowledge of histoplasmosis pathophysiology and treatment.  相似文献   
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Marine Biotechnology - The inorganic part of marine sponges, called Biosilica (BS), presents an osteogenic potential and the ability of consolidating fractures. Moreover, 3D printing technique is...  相似文献   
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