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571.
Carlos Vinicius Barros Oliveira Patric Anderson Gomes da Silva Saulo Relison Tintino Cathia Cecília Coronel Maria Celeste Vega Gomez Mírian Roln Francisco Assis Bezerra da Cunha Maria Flaviana Bezerra Morais-Braga Henrique Douglas Melo Coutinho Abolghasem Siyadatpanah Polrat Wilairatana Jean Paul Kamdem Luiz Marivando Barros Antonia Eliene Duarte Pedro Silvino Pereira 《Molecules (Basel, Switzerland)》2022,27(7)
Weeds are an important source of natural products; with promising biological activity. This study investigated the anti-kinetoplastida potential (in vitro) to evaluate the cytotoxicity (in vitro) and antioxidant capacity of the essential oil of Rhaphiodon echinus (EORe), which is an infesting plant species. The essential oil was analyzed by GC/MS. The antioxidant capacity was evaluated by reduction of the DPPH radical and Fe3+ ion. The clone Trypanosoma cruzi CL-B5 was used to search for anti-epimastigote activity. Antileishmanial activity was determined using promastigotes of Leishmania braziliensis (MHOM/CW/88/UA301). NCTC 929 fibroblasts were used for the cytotoxicity test. The results showed that the main constituent of the essential oil was γ-elemene. No relevant effect was observed concerning the ability to reduce the DPPH radical; only at the concentration of 480 μg/mL did the essential oil demonstrate a high reduction of Fe3+ power. The oil was active against L. brasiliensis promastigotes; but not against the epimastigote form of T. cruzi. Cytotoxicity for mammalian cells was low at the active concentration capable of killing more than 70% of promastigote forms. The results revealed that the essential oil of R. echinus showed activity against L. brasiliensis; positioning itself as a promising agent for antileishmanial therapies. 相似文献
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573.
Abdollah Ardebili Mohammad Hassan Pouriayevali Sahar Aleshikh Marziyeh Zahani Mehdi Ajorloo Ahdieh Izanloo Abolghasem Siyadatpanah Hadi Razavi Nikoo Polrat Wilairatana Henrique Douglas Melo Coutinho 《Molecules (Basel, Switzerland)》2021,26(22)
The treatment of viral disease has become a medical challenge because of the increasing incidence and prevalence of human viral pathogens, as well as the lack of viable treatment alternatives, including plant-derived strategies. This review attempts to investigate the trends of research on in vitro antiviral effects of curcumin against different classes of human viral pathogens worldwide. Various electronic databases, including PubMed, Scopus, Web of Science, and Google Scholar were searched for published English articles evaluating the anti-viral activity of curcumin. Data were then extracted and analyzed. The forty-three studies (published from 1993 to 2020) that were identified contain data for 24 different viruses. The 50% cytotoxic concentration (CC50), 50% effective/inhibitory concentration (EC50/IC50), and stimulation index (SI) parameters showed that curcumin had antiviral activity against viruses causing diseases in humans. Data presented in this review highlight the potential antiviral applications of curcumin and open new avenues for further experiments on the clinical applications of curcumin and its derivatives. 相似文献
574.
Based on the diagonalization of an effective Hamiltonian, we investigate the role of electronic correlation on the aromatic behavior of polycyclic aromatic hydrocarbons (PAHs). We show that for benzene and several examples of PAHs, a singular change in the electronic distribution happens at a relatively narrow range of the Coulomb interaction strength; in each case, the CC bond distribution pattern agrees with the known chemical behavior of the corresponding compound. We explore the link between electronic correlation and information entropy and show that several signatures of fluctuations in the one-particle entropy occur at the same range of values of the Coulomb parameter that correspond to a realistic bond-order distribution of the PAHs. These results indicate that the singular stability of the electronic distribution of aromatic compounds is associated with an optimum range of correlation effects, which can be understood in terms of the entanglement of the two sub-lattices of alternating carbon atoms and the presence of a localization transition of the overall electronic density. 相似文献
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Experimental Techniques - Structural components may contain cracks, and for these components a crack tip represents a highly singular stress. The evaluation of the associated strain gradient is... 相似文献
579.
Eduardo J. Crevelin Antônio E. M. Crotti Tiago D. Zucchi Itamar S. Melo Luiz A. B. Moraes 《Journal of mass spectrometry : JMS》2014,49(11):1117-1126
Actinomycetes, especially those belonging to the genus Streptomyces, are economically important from a biotechnological standpoint: they produce antibiotics, anticancer compounds and a variety of bioactive substances that are potentially applicable in the agrochemical and pharmaceutical industries. This paper combined accurate‐mass electrospray tandem mass spectrometry in the full scan and product ion scan modes with compounds library data to identify the major compounds in the crude extract produced by Streptomyces sp. AMC 23; it also investigated how sodiated nonactin ([M + Na]+) fragmented. Most product ions resulted from elimination of 184 mass units due to consecutive McLafferty‐type rearrangements. The data allowed identification of four macrotetrolides homologous to nonactin (monactin, isodinactin, isotrinactin/trinactin and tetranactin) as well as three related linear dimer compounds (nonactyl nonactoate, nonactyl homononactoate and homononactyl homononactoate). The major product ions of the sodiated molecules of these compounds also originated from elimination of 184 and 198 mass units. UPLC‐MS/MS in the neutral loss scan mode helped to identify these compounds on the basis of the elimination of 184 and 198 mass units. This method aided monitoring of the relative production of these compounds for 32 days and revealed that the biosynthetic process began with increased production of linear dimers as compared with macrotetrolides. These data could facilitate dereplication and identification of these compounds in other microbial crude extracts. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
580.
During the transition from deconfined to hadronic stage the firaball in ultrarelativistic nuclear collisions can fragment.
We propose a method which uses the Kolmogorov-Smirnov test to identify whether the fireball has fragmented or not. We test
the method on artificial data generated by a Monte Carlo event generator which simulates particle emission from a fragmented
fireball. 相似文献