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231.
232.
Garnica-Romo Ma. Guadalupe Coria-Caballero Vanessa Tranquilino-Rodríguez Eunice Dasgupta-Schubert Nabanita Villicaña-Méndez Maricela Agarwal Vivechana Martínez-Flores Héctor Eduardo 《Journal of Inorganic and Organometallic Polymers and Materials》2021,31(8):3406-3415
Journal of Inorganic and Organometallic Polymers and Materials - A simple and ecologically friendly method was used for the synthesis of mucilage/proteins (M/P) stabilized silver nanoparticles... 相似文献
233.
Martha Cecilia Rosales Hernndez Leticia Guadalupe Fragoso Morales Jos Correa Basurto Marycruz Olvera Valdez Efrn Venancio García Bez Dania Guadalupe Romn Vzquez Ana Paola Anaya García Alejandro Cruz 《International journal of molecular sciences》2022,23(21)
Alzheimer’s disease (AD) is a progressive neurodegenerative disorder. Inhibiting acetylcholinesterase (AChE), amyloid beta (Aβ1-42) aggregation and avoiding the oxidative stress could prevent the progression of AD. Benzothiazole groups have shown neuroprotective activity whereas isothioureas groups act as AChE inhibitors and antioxidants. Therefore, 22 benzothiazole-isothiourea derivatives (3a–v) were evaluated by docking simulations as inhibitors of AChE and Aβ1-42 aggregation. In silico studies showed that 3f, 3r and 3t had a delta G (ΔG) value better than curcumin and galantamine on Aβ1-42 and AChE, respectively. The physicochemical and pharmacokinetics predictions showed that only 3t does not violate Lipinski’s rule of five, though it has moderated cytotoxicity activity. Then, 3f, 3r and 3t were synthetized and chemically characterized for their in vitro evaluation including their antioxidant activity and their cytotoxicity in PC12 cells. 3r was able to inhibit AChE, avoid Aβ1-42 aggregation and exhibit antioxidant activity; nevertheless, it showed cytotoxic against PC12 cells. Compound 3t showed the best anti-Aβ1-42 aggregation and inhibitory AChE activity and, despite that predictor, showed that it could be cytotoxic; in vitro with PC12 cell was negative. Therefore, 3t could be employed as a scaffold to develop new molecules with multitarget activity for AD and, due to physicochemical and pharmacokinetics predictions, it could be administered in vivo using liposomes due to is not able to cross the BBB. 相似文献
234.
Andrés Castro-Ruíz Heriberto Rodríguez-Tobías Gustavo A. Abraham Guadalupe Rivero Graciela Morales 《应用聚合物科学杂志》2020,137(9):48429
This investigation addresses the design of a series of poly(acrylonitrile-butadiene-styrene)/polyacrylonitrile–zinc oxide(ABS/PAN–ZnO) membranes by coaxial electrospinning. In the first instance, an optimization of ABS and PAN electrospinning was performed, thus establishing suitable compositional and processing parameters for obtaining homogenous fibers. Then, coaxial electrospinning of ABS and PAN solutions containing different amount of ZnO nanoparticles was carried out. The coaxial morphology of the nanofibers and ZnO distribution/dispersion were studied by the combination of several techniques such as scanning electron microscopy, X-ray energy dispersive analysis, contact angle, and thermogravimetric analysis. The performance of the obtained membranes for chromium (VI) ions removal from aqueous solutions was assessed by photoreduction using ultraviolet–visible spectroscopy. Electrospun mats composed of ABS (core)/PAN (sheath) embedded with 30 wt % of ZnO nanoparticles exhibited the highest chromium photoreduction (about 80%), suggesting the potential use of these membranes as filters for water purification. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48429. 相似文献
235.
Widianta Gomulya Guadalupe Diaz Costanzo Elton J. Figueiredo de Carvalho Satria Zulkarnaen Bisri Vladimir Derenskyi Martin Fritsch Nils Fröhlich Sybille Allard Pavlo Gordiichuk Andreas Herrmann Siewert Jan Marrink Maria Cristina dos Santos Ulrich Scherf Maria Antonietta Loi 《Advanced materials (Deerfield Beach, Fla.)》2013,25(21):2948-2956
236.
Diana Cecilia Maya-Cortés Juan de Dios Figueroa Cárdenas Ma. Guadalupe Garnica-Romo Ruth Alfaro Cuevas-Villanueva Raúl Cortés-Martínez José Juan Véles-Medina & Héctor Eduardo Martínez-Flores 《International Journal of Food Science & Technology》2010,45(1):23-28
Corn tortillas are produced using the traditional nixtamalisation process (TP). Nevertheless, one of the greatest problems that the tortilla industry faces is the high level of losses of solids. The aim of this research was to evaluate the nutritional value of a whole-grain tortilla, produced using an ecological process (EP). In the EP corn was cooked at 90 °C with 1.8% (w/w) calcium sulphate. The grains were steeped, washed and grounded to obtain the masa, which was baked to produce tortillas. Also, tortillas were prepared using the TP and following the same steps as those used in the EP, except that 1.0% (w/w) of calcium hydroxide was used. The tortillas from EP retained 14.05, 6.03, and 54.02% more fat, protein and fibre than tortillas produced by the TP. The PER value of rats fed whole-grain tortillas (1.81) was not different from that of rats fed the traditional tortillas (1.85). 相似文献
237.
Guadalupe del C. Pizarro Oscar G. Marambio Manuel Jeria-Orell Margarita R. Huerta Bernabé L. Rivas Wolf D. Habicher 《应用聚合物科学杂志》2008,108(6):3982-3989
Radical copolymerization of 1-vinyl-2-pyrrolidone with itaconic acid at different feed monomer ratios (75–25 mol %) were investigated. The copolymers were characterized by elemental analysis, Fourier transform infrared (FTIR), 1H and 13C NMR spectroscopy. The copolymer composition was determined from elemental analysis and found to be statistical copolymers. Additionally, viscosimetric measurements, molecular weight, and polydispersity have been determined. The metal complexation of poly(1-vinyl-2-pyrrolidone-co-itaconic acid) for the metal ions such as Cr(III), Co (II), Zn(II), Ni(II), Cu(II), Cd(II), and Fe(III) were investigated at pH 3, 5, and 7 in aqueous solution. The metal ion interaction with hydrophilic polymers was determined as a function of the pH and filtration factor. Poly(1-vinyl-2-pyrrolidone-co-itaconic acid) showed a high affinity for the metal ions at pH 5 and 7. The poly(NVP-co-IA), with a copolymer composition of 29 : 71 mol % (PVA-3), presented the highest metal ion retention values, particularly at higher pHs, at which the carboxylic acid groups are nonprotonated and could easily coordinate with the metal ions. According to the interaction pattern obtained, Cr(II), Zn(II), Pb(II), and Ni(II) formed the most stable complexes at pH 7. The thermal behaviors of the copolymer and polymer metal complex were characterized using differential scanning calorimetry (DSC) and thermogravimetry techniques under nitrogen atmosphere. The copolymers present high thermal stability and do not present glass transition in DSC curves between 25 and 500°C. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci 2008 相似文献
238.
Montserrat Trilla Guadalupe Borja Roser Pleixats Michel Wong Chi Man Catherine Bied Joël J.E. Moreau 《Advanced Synthesis \u0026amp; Catalysis》2008,350(16):2566-2574
The systems formed by palladium acetate [Pd(OAc)2] and hybrid silica materials prepared by sol‐gel from monosilylated imidazolium and disilylated dihydroimidazolium salts show catalytic activity in Suzuki–Miyaura cross‐couplings with challenging aryl bromides and chlorides. They are very efficient as recoverable catalysts with aryl bromides. Recycling is also possible with aryl chlorides, although with lower conversions. In situ formation of palladium nanoparticles has been observed in recycling experiments. 相似文献
239.
Nanocomposites based on resol resin and layered silicates were obtained by in situ polymerization. An increment in the viscosity and in the content of free formaldehyde in the prepolymer with the addition of clay was observed. It could be attributed to the entrance of small phenol molecules into the galleries modifying the concentration of reagent enabled to react outside the clay galleries. The composites were cured by temperature and it was observed that the type of clay affect their dispersion in the polymer. The unmodified Cloisite® Na+ montmorillonite (CNa) was the best dispersed in the polymeric matrix, whereas the modified montmorillonites (MMTs) showed an interlayer contraction after curing. It seems to be due to the loss of modifiers from the clay or to the different rate of curing inside and outside the galleries. In addition, the composite containing CNa presented higher crosslinking density than the others with modified MMTs. More adhesive strength was observed in that composite as well. It was related with the void content and the polarity of the samples. These results were compared with the ones obtained when the nanocomposites were synthesized by mixing the clay with the prepolymer. The nanocomposites with the addition of CNa showed similar properties independent of the way of synthesis used. However, it seems that the modified clays are better dispersed by mixing with the prepolymer than by in situ polymerization. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
240.
Hugo Mendoza Tellez Joaquín Palacios Alquisira José Guadalupe López‐Cortés Cecilio Alvarez‐Toledano 《应用聚合物科学杂志》2010,116(5):2816-2824
The microwave assisted polycondensation of two polyimides were studied using pyromellitic dianhydride (PMDA), and 4,4′‐(hexafluoroisopropyliden)diphthalic anhydride (6FDA) as dianhydride monomers and 2,4,6‐trimethyl‐m‐phenylenediamine (TrmPD), as diamine monomer, under microwave irradiation in DMF and DMSO solvents. The structure and performance of polymers were characterized by Fourier Transform Infrared Spectroscopy (FTIR), viscosity, density, and Thermogravimetric Analysis (TGA). The results show that the polyimides can be obtained in a short reaction time with high intrinsic viscosity and high yield. The effect of the presence of a bridging group, ? C(CF3)2? , in the monomer structure is apparent in the permeability parameters of the macromolecules as polymer (6FDA‐TrmPD) always presents better results than polymer (PMDA‐TrmPD). Properties as density and Tg increases with the time exposition to the microwave irradiation. Polyimides obtained present good thermal properties because they began to lose weight in a range of 8–16% at high temperature as 450°C. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献