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971.
Adair Divino da Silva Badaro Rmulo Sousa Muhammad Naeem Maxwell Santana Librio Rayane Saory Medeiros dos Santos Flaviane camara de Souza Thrcio Costa Michele Feitor Javed Iqbal 《先进技术聚合物》2020,31(10):2229-2238
The mosquito‐transmitted diseases are of serious concern and are affecting several millions of peoples worldwide. Instead of medication afterward the disease initiated, self‐protection against the mosquito's is preferable, specifically in endemic areas. For this purpose, the permethrin coated clothing is a suitable choice to avoid mosquitos' bites. Unfortunately, the permethrin coating on fabrics is not long‐lasting, and its laundering resistance is very low on hydrophobic fabric. In this study, the effect of plasma surface modification of PET fabric on the adhesion of permethrin and its laundering resistance are evaluated. The plasma processing is carried out in nitrogen, oxygen, and nitrogen–oxygen mixture plasma. The samples are analyzed using Fourier Transform Infrared spectroscopy, X‐ray photoelectron spectroscopy, scanning electron microscope and chromatography. The results show that the oxygen plasma pre‐treated samples exhibit the higher residual contents of permethrin after 60 wash cycles as compared with other gasses. Without plasma pre‐treatment, the 95% loss, whereas the sample with oxygen plasma pre‐treatment shows that only 22% loss of initial concentration of permethrin occurs after washing. This study shows that plasma pre‐treatment is valuable to improve the absorption of permethrin in PET and its laundering‐resistance. As plasma treatment is a cost‐effective technique, it needs less processing time and eco‐friendly, thus it is a great choice to deposit long‐lasting permethrin coating by plasma pre‐treatment, instead of conventional binding agents. Remarkably, the plasma treatment technique is a well‐established and industrially acceptable technique, thus expected to be of noteworthy importance for insecticide garments manufacturers. 相似文献
972.
Edson Roberto da Silva Júlio Abel Alfredo dos Santos Simone Come Simone Brogi Vincenzo Calderone Giulia Chemi Giuseppe Campiani Trícia Maria Ferrreira de Sousa Oliveira Thanh-Nhat Pham Marc Pudlo Corine Girard Claudia do Carmo Maquiaveli 《Molecules (Basel, Switzerland)》2020,25(22)
Caffeic acid and related natural compounds were previously described as Leishmania amazonensis arginase (L-ARG) inhibitors, and against the whole parasite in vitro. In this study, we tested cinnamides that were previously synthesized to target human arginase. The compound caffeic acid phenethyl amide (CAPA), a weak inhibitor of human arginase (IC50 = 60.3 ± 7.8 μM) was found to have 9-fold more potency against L-ARG (IC50 = 6.9 ± 0.7 μM). The other compounds that did not inhibit human arginase were characterized as L-ARG, showing an IC50 between 1.3–17.8 μM, and where the most active was compound 15 (IC50 = 1.3 ± 0.1 μM). All compounds were also tested against L. amazonensis promastigotes, and only the compound CAPA showed an inhibitory activity (IC50 = 80 μM). In addition, in an attempt to gain an insight into the mechanism of competitive L-ARG inhibitors, and their selectivity over mammalian enzymes, we performed an extensive computational investigation, to provide the basis for the selective inhibition of L-ARG for this series of compounds. In conclusion, our results indicated that the compounds based on cinnamoyl or 3,4-hydroxy cinnamoyl moiety could be a promising starting point for the design of potential antileishmanial drugs based on selective L-ARG inhibitors. 相似文献
973.
Tainá Caroline dos Santos Kaline de Brito Sousa Lucas Andreo Andreia Martinelli Maria Fernanda Setubal Destro Rodrigues Sandra Kalil Bussadori Kristianne Porta Santos Fernandes Raquel Agnelli Mesquita-Ferrari 《Photochemistry and photobiology》2020,96(4):906-916
Moderate levels of a proinflammatory macrophages phenotype are indispensable and play an important role in the skeletal muscle repair process since this response depends on their secreted products concentration to influence and modulate muscle inflammation as well as the differentiation of myoblasts. This study investigated the effects of photobiomodulation (PBM) on undifferentiated and differentiation-induced C2C12 myoblasts cultivated in different concentrations of M1 phenotype macrophage-conditioned media of J774 cells (MCM1) also submitted to PBM using the same irradiation parameters. Irradiation was performed once with low-level laser (780 nm, 70 mW, 1 J) and was evaluated cell viability, proliferation and differentiation, nitric oxide (NO) synthesis and IL-6 and TNF-α protein levels 24 and 48 h after C2C12 irradiation. PBM treatment in undifferentiated myoblasts exhibited lower IL-6 levels in the presence of nonirradiated MCM1 at both concentrations. Myoblasts in proliferation condition cultivated with irradiated MCM1 showed lower IL-6 and TNF-α levels after 48 h in the presence of both concentrations evaluated. PBM induced a decrease in the synthesis of NO on undifferentiated and differentiation-induced myoblasts. PBM was able to reduce the level of proinflammatory protein and markers, which are important to allow the differentiation of myoblasts during the muscle repair process. 相似文献
974.
Cinthia Meirelly de Araújo Elpídio Carlos Eduardo de Araújo Padilha Francisco Canindé de Sousa Júnior Ruthinéia Jéssica Alves do Nascimento Camilla Milena de Araújo Elpídio Sérgio Dantas de Oliveira Júnior Gorete Ribeiro de Macedo Everaldo Silvino dos Santos 《Chromatographia》2018,81(10):1355-1364
This study deals with the fabrication and characterization of a pellicular adsorbent appropriate for the expanded bed adsorption (EBA) process. The synthesized adsorbent has an yttria-stabilized zirconia nucleus coated with agarose. Morphological analysis of the coated particles was performed by light-scattering microscopy and showed an average diameter of 197.54 and 202.25 µm, for the nucleus and coated particle, respectively. A screening for the reactive dyes reactive blue 19 (RB19), reactive blue 21 (RB21) and reactive orange 107 (RO107) was performed after immobilization onto the pellicular adsorbent by changing the pH, aiming at finding the binding capacity of these to adsorb bovine serum albumin (BSA). The reactive orange 107 was selected and it was more stable at pH 4.5. Study of the kinetics between BSA and the dye-immobilized particle showed that equilibrium is reached before 1 h. The adsorption isotherm of BSA onto RO107-immobilized adsorbent fitted the Langmuir model showing a qm = 102.328 mg BSA/mL of adsorbent. The pellicular adsorbent also showed good expansion even at a high operating flow rate. Therefore, at a linear velocity as high as 2725 cm/h, a dynamic capacity of 15.7 mg of BSA/mL of adsorbent was obtained. 相似文献
975.
976.
Antônio Gomes dos Santos Neto Camila Silva de Sousa André da Silva Freires Saimon Moraes Silva Hudson Zanin Flavio Santos Damos Rita de Cássia Silva Luz 《Journal of Solid State Electrochemistry》2018,22(5):1385-1394
Imipramine (IMP), a tricyclic antidepressant drug, is commonly prescribed for treatment of psychiatric patients suffering from different forms of depression. The appropriate amount of drug intake is crucial to ensure the optimum therapeutic effects minimizing severe collateral effects and toxicity. Therefore, the monitoring of imipramine is essential for its clinical applications. Herein, we report an electrochemical sensor based on a composite of ferrocenecarboxylic acid (FCA), β-cyclodextrin (CD), and oxidized multi-walled carbon nanotubes (f-CNT) modified glassy carbon electrode for detection of IMP at low potential. The electrochemical behavior of the proposed sensor was characterized by scanning electron microscopy, Raman spectroscopy, and cyclic voltammetry. The results show that imipramine determination using the proposed sensor occurs around 0 V vs Ag/AgCl in phosphate buffer pH 7.0. The calibration curves were obtained by cyclic voltammetry and differential pulse voltammetry, with linear ranges of 10 to 350 μmol L?1 and 0.1 to 10 μmol L?1, respectively. A detection limit of 0.03 μmol L?1 was obtained for the detection of IMP. The sensor was applied for IMP determination in psychotropic drugs and urine samples and the results show a recovery percentage between 99 and 101% for the analyte. 相似文献
977.
978.
Daniel Dall’Onder dos Santos Sérgio L. Frey Mônica F. Naccache Paulo R. de Souza Mendes 《Rheologica Acta》2014,53(1):31-41
The steady flow of incompressible elasto-viscoplastic liquids through a planar expansion–contraction is investigated. A novel constitutive model is employed to describe the mechanical behavior of the flowing liquids. Numerical solutions of the constitutive and conservation equations were obtained via a finite element method to investigate the role of elasticity, yield stress, and inertia. The fields of velocity, stress, elastic strain, and rate of strain were obtained for different combinations of the governing parameters. It was observed that these fields, as well as the shape and position of the yield surface, are all strong functions of elasticity, yield stress, and inertia. The trends observed agree well with previous numerical and visualization results available in the literature. The present work offers a detailed study on the effects of elasticity, presenting, in particular, the fields of elastic strain. 相似文献
979.
Ramón E.R. González Sérgio Coutinho Rita Maria Zorzenon dos Santos Pedro Hugo de Figueirêdo 《Physica A》2013
The dynamics of human immunodeficiency virus infection under antiretroviral therapy is investigated using a cellular automata model where the effectiveness of each drug is self-adjusted by the concentration of CD4+ T infected cells present at each time step. The effectiveness of the drugs and the infected cell concentration at the beginning of treatment are the control parameters of the cell population’s dynamics during therapy. The model allows describing processes of mono and combined therapies. The dynamics that emerges from this model when considering combined antiretroviral therapies reproduces with fair qualitative agreement the phases and different time scales of the process. As observed in clinical data, the results reproduce the significant decrease in the population of infected cells and a concomitant increase of the population of healthy cells in a short timescale (weeks) after the initiation of treatment. Over long time scales, early treatment with potent drugs may lead to undetectable levels of infection. For late treatment or treatments starting with a low density of CD4+ T healthy cells it was observed that the treatment may lead to a steady state in which the T cell counts are above the threshold associated with the onset of AIDS. The results obtained are validated through comparison to available clinical trial data. 相似文献
980.
Fluxes of cosmic rays: a delicately balanced stationary state 总被引:1,自引:0,他引:1
The analysis of cosmic rays fluxes as a function of energy reveals a knee slightly below 1016 eV and an ankle close to 1019 eV. Their physical origins remain up to now quite enigmatic; in particular, no elementary process is known which occurs at energies close to 1016 eV. We propose a phenomenological approach along the lines of nonextensive statistical mechanics, a formalism which contains Boltzmann–Gibbs statistical mechanics as a particular case. The knee then appears as a crossover between two fractal-like thermal regimes, the crossover being caused by process occurring at energies ten million times lower than that of the knee, in the region of the quark hadron transition (109 eV). This opens the door to an unexpected standpoint for further clarifying the phenomenon. 相似文献