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31.
32.
R. Fausto L.A.E. Batista De Carvalho J.J.C. Teixeira-Dias 《Journal of computational chemistry》1992,13(7):799-809
The internal rotation in the HC(?X)YCH2CH3 (X, Y = O or S) series of molecules was studied by the ab initio SCF-MO method using 3-21G and 3-21G + d(ζ = 0.65S) basis sets. Energies and structures of several conformations of these molecules, determined by gradient geometry refinement, are reported and used to assess the effects of oxygen-by-sulphur substitution on molecular properties. The nature and relative importance of intramolecular interactions involving both the ? CH2CH3 and the HC(?X)Y (X, Y = O or S) fragments are also discussed. © 1992 by John Wiley & Sons, Inc. 相似文献
33.
S. M. Dal Bosco R. S. Jimenez C. Vignado J. Fontana B. Geraldo F. C. A. Figueiredo D. Mandelli W. A. Carvalho 《Adsorption》2006,12(2):133-146
The adsorption capacities of commercial and Brazilian natural clays were evaluated to test their applications in wastewater
control. We investigated the process of sorption of manganese(II) and cadmium(II) present in synthetic aqueous effluents,
by calculating the adsorption isotherms at 298 K using batch experiments. The influence of temperature and pH on the adsorption
process was also studied. Adsorption of metals was best described by a Langmuir isotherm, with values of Q
0 parameter, which is related to the sorption capacity, corresponding to 6.3 mg g− 1 for K-10/Cd(II), 4.8 mg g− 1 for K-10/Mn(II), 11.2 mg g− 1 for NT-25/Cd(II) and 6.0 mg g− 1 for NT-25/Mn(II). We observed two distinct adsorption mechanisms that may influence adsorption. At the first 5 min of interaction,
a cation exchange mechanism that takes place at exchange sites located on (001) basal planes is predominant. This process
is inhibited by low pH values. After this first and fast step, a second sorption mechanism can be related to formation of
inner-sphere surface complexes, which is formed at edges of the clay. The rate constants and the initial sorption rates correlate
positively with temperature in all studied systems, denoting the predominance of a physisorption process. The addition of
complexing agents that are incorporated within the K10 structure, enhance metal uptake by the adsorbent. The results have
shown that both Cd(II) and Mn(II) were totally retained from a 50 mg L− 1 solution when K10 grafted with ammonium pyrrolidinedithiocarbamate (APDC) was used as adsorbent. 相似文献
34.
Ana Valria de Oliveira Braz Mariana Carvalho Rodrigues Philippe Alencar Araújo Maia Ana Paula Dantas Pereira Jussara de Lima Silva Francisco Antonio Vieira dos Santos Luiz Everson da Silva Wanderley do Amaral Maura Lins dos Santos Henrique Douglas Melo Coutinho Tomasz Baj Grayna Kowalska Radosaw Kowalski Edinardo Fagner Ferreira Matias 《Molecules (Basel, Switzerland)》2022,27(18)
Commercialized mouthwashes are generally expensive for the most financially vulnerable populations. Thus, several studies evaluate the antimicrobial potential of herbal products, such as essential oils, to reduce the activity of microorganisms in the mouth. The objective of this research was to carry out the chemical characterization and antibacterial activity of the essential oil of Piper mosenii (EOPm), providing data that enable the development of a low-cost mouthwash formulation aimed at vulnerable communities. The analysis of the antibacterial potential and modulator of bacterial resistance was verified by the microdilution method to determine the minimum inhibitory concentration-MIC. The chemical components were characterized by gas chromatography coupled to mass spectrometry, where 23 chemical constituents were detected, with α-pinene, being the major compound. The EOPm showed a MIC ≥ 1024 µg/mL for all bacterial strains used in the tests. When the EOPm modulating activity was evaluated together with chlorhexidine, mouthwash and antibiotics against bacterial resistance, the oil showed a significant synergistic effect, reducing the MIC of the products tested in combination, in percentages between 20.6% to 96.3%. Therefore, it is recommended to expand the tests with greater variation of EOPm concentration and the products used in this research, in addition to the evaluation of toxicity and in vivo tests, seeking the development of a possible formulation of mouthwash accessible to the vulnerable population. 相似文献
35.
Renata Quartieri Nascimento Cludio Vaz Di Mambro Ribeiro Nelson Barros Colauto Larissa da Silva Paulo Vitor Frana Lemos Ederlan de Souza Ferreira Giani Andrea Linde Bruna Aparecida Souza Machado Pedro Paulo Lordelo Guimares Tavares Aline Camaro Telles Biasoto Marcelo Andres Umsza Guez Natlia Carvalho Denílson de Jesus Assis Jania Betnia Alves da Silva Carolina Oliveira de Souza 《Molecules (Basel, Switzerland)》2022,27(20)
Edible insects are a potential alternative food source of high feed conversion efficiency and protein content. Zophobas atratus is an edible insect that adapts to different diets, enabling sustainable rearing by adding value to by-products and agro-industrial residues. This study aimed to evaluate the performance and nutritional characterization of Zophobas atratus larvae fed with different proportions of grape residue. Physicochemical analysis of the diets and larvae (AOAC procedures), fatty acid profile (chromatographic techniques), metals and non-metals (inductively coupled plasma optical emission spectrometry), larval mass gain, feed conversion efficiency, and mortality rate were assessed. The replacement of 25% of the conventional diet with grape residue increased lipid, ash, and fiber contents and reduced protein, carbohydrates, and energy. It promoted greater mass gain, lower mortality rate, and reduced larval growth time by 51%. Among the replacements, 25% resulted in the second-highest content of calcium, sodium, magnesium, and zinc, and the lowest content of potassium and phosphorus in the larvae. The 100% replacement resulted in the highest amounts of C18:2n6 (27.8%), C18:3n3 (2.2%), and PUFA (30.0%). Replacing 25% of the conventional diet with grape residue is equivalent to the conventional diet in many aspects and improves several larvae performance indices and nutritional values. 相似文献
36.
37.
Laís Peres Silva Ivanilson Pimenta Santos Dahara Keyse Carvalho Silva Bruna Padilha Zurita Claro dos Reis Cssio Santana Meira Marcos Venícius Batista de Souza Castro Jos Maurício dos Santos Filho Joo Honorato de Araujo-Neto Javier Alcides Ellena Rafael Gomes da Silveira Milena Botelho Pereira Soares 《Molecules (Basel, Switzerland)》2022,27(23)
Immunomodulatory agents are widely used for the treatment of immune-mediated diseases, but the range of side effects of the available drugs makes necessary the search for new immunomodulatory drugs. Here, we investigated the immunomodulatory activity of new ferrocenyl-N-acyl hydrazones derivatives (SintMed(141–156). The evaluated N-acyl hydrazones did not show cytotoxicity at the tested concentrations, presenting CC50 values greater than 50 µM. In addition, all ferrocenyl-N-acyl hydrazones modulated nitrite production in immortalized macrophages, showing inhibition values between 14.4% and 74.2%. By presenting a better activity profile, the ferrocenyl-N-acyl hydrazones SintMed149 and SintMed150 also had their cytotoxicity and anti-inflammatory effect evaluated in cultures of peritoneal macrophages. The molecules were not cytotoxic at any of the concentrations tested in peritoneal macrophages and were able to significantly reduce (p < 0.05) the production of nitrite, TNF-α, and IL-1β. Interestingly, both molecules significantly reduced the production of IL-2 and IFN-γ in cultured splenocytes activated with concanavalin A. Moreover, SintMed150 did not show signs of acute toxicity in animals treated with 50 or 100 mg/kg. Finally, we observed that ferrocenyl-N-acyl hydrazone SintMed150 at 100 mg/kg reduced the migration of neutrophils (44.6%) in an acute peritonitis model and increased animal survival by 20% in an LPS-induced endotoxic shock model. These findings suggest that such compounds have therapeutic potential to be used to treat diseases of inflammatory origin. 相似文献
38.
Gabriela Corrêa Carvalho Gabriel Davi Marena Gabriela Ricci Leonardi Rafael Miguel Sbio Ione Corrêa Marlus Chorilli Tais Maria Bauab 《Molecules (Basel, Switzerland)》2022,27(23)
Commonly found colonizing the human microbiota, Candida albicans is a microorganism known for its ability to cause infections, mainly in the vulvovaginal region known as vulvovaginal candidiasis (VVC). This pathology is, in fact, one of the main C. albicans clinical manifestations, changing from a colonizer to a pathogen. The increase in VVC cases and limited antifungal therapy make C. albicans an increasingly frequent risk in women’s lives, especially in immunocompromised patients, pregnant women and the elderly. Therefore, it is necessary to develop new therapeutic options, especially those involving natural products associated with nanotechnology, such as lycopene and mesoporous silica nanoparticles. From this perspective, this study sought to assess whether lycopene, mesoporous silica nanoparticles and their combination would be an attractive product for the treatment of this serious disease through microbiological in vitro tests and acute toxicity tests in an alternative in vivo model of Galleria mellonella. Although they did not show desirable antifungal activity for VVC therapy, the present study strongly encourages the use of mesoporous silica nanoparticles impregnated with lycopene for the treatment of other human pathologies, since the products evaluated here did not show toxicity in the in vivo test performed, being therefore, a topic to be further explored. 相似文献
39.
Robson Araújo de Freitas Junior Paloma Kênia de Moraes Berenguel Lossavaro Cndida Aparecida Leite Kassuya Edgar Julian Paredes-Gamero Nelson Carvalho Farias Júnior Maria Inês Lenz Souza Francielli Maria de Souza Silva-Comar Roberto Kenji Nakamura Cuman Denise Brentan Silva Mnica Cristina Toffoli-Kadri Saulo Euclides Silva-Filho 《Molecules (Basel, Switzerland)》2022,27(12)
The aim of this study is to evaluate the phytochemical profile, oral acute toxicity, and the effect of ylang-ylang (Cananga odorata Hook. F. & Thomson) essential oil (YEO) on acute inflammation. YEO was analyzed by gas chromatography/mass spectrometry. For in vitro tests, YEO was assessed using cytotoxicity, neutrophil chemotaxis induced by N-formyl methionyl leucyl phenylalanine (fMLP), and phagocytic activity tests. YEO was orally administered in zymosan-induced peritonitis, carrageenan-induced leukocyte rolling, and adhesion events in the in situ microcirculation model and in carrageenan-induced paw edema models. YEO (2000 mg/kg) was also tested using an acute toxicity test in Swiss mice. YEO showed a predominance of benzyl acetate, linalool, benzyl benzoate, and methyl benzoate. YEO did not present in vitro cytotoxicity. YEO reduced the in vitro neutrophil chemotaxis induced by fMLP and reduced the phagocytic activity. The oral treatment with YEO reduced the leukocyte recruitment and nitric oxide production in the zymosan-induced peritonitis model, reduced rolling and adherent leukocyte number induced by carrageenan in the in situ microcirculation model, and reduced carrageenan-induced edema and mechanical hyperalgesia. YEO did not present signs of toxicity in the acute toxicity test. In conclusion, YEO affected the leukocyte activation, and presented antiedematogenic, anti-hyperalgesic, and anti-inflammatory properties. 相似文献
40.