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1.
Yong-Seo Park Seong-Gook Kang Alma Leticia Martinez Ayala Olga Martín-Belloso Shela Gorinstein 《LWT》2006,39(7):748-755
Fresh persimmons were subjected to two different processes: sun-drying during 1 month and dehydration at 60 °C during 12 h. To assess the effect of this process on nutritional and health-related properties of persimmons dietary fibers, minerals, trace elements, polyphenols and the total radical scavenging activities (TRSAs) were determined before and after processing. It was found that the contents of dietary fibers, minerals and trace elements in fresh and dried persimmons fruits were comparable. Total polyphenols in fresh persimmons was higher than in dried fruits (1.3 vs. 0.9 and 0.8 mg/100 g FW, respectively) and percentage of inhibition was higher than in dried fruits (70% vs. 59% and 55% and 58% vs. 53% and 46% for 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2′-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) [ABTS] radicals, respectively (P>0.05 in all cases). In conclusion: (1) the differences in the contents of dietary fibers, minerals and trace elements in fresh and dried persimmons are not significant; (2) the contents of polyphenols and the level of the TRSA are higher in fresh persimmons than in dried fruits; however, both variables are also high in dried persimmons; (3) when fresh fruits are not available, proper dried persimmons could be used as a valuable substitute. 相似文献
2.
Cytotoxic Activity and Structure–Activity Relationship of Triazole‐Containing Bis(Aryl Ether) Macrocycles 下载免费PDF全文
Dr. Eduardo Hernández‐Vázquez Dr. Alejandra Chávez‐Riveros Dr. Adriana Romo‐Pérez María Teresa Ramírez‐Apán Dr. Alma D. Chávez‐Blanco Dr. Rocío Morales‐Bárcenas Dr. Alfonso Dueñas‐González Dr. Luis D. Miranda 《ChemMedChem》2018,13(12):1193-1209
Cancer continues to be a worldwide health problem. Certain macrocyclic molecules have become attractive therapeutic alternatives for this disease because of their efficacy and, frequently, their novel mechanisms of action. Herein, we report the synthesis of a series of 20‐, 21‐, and 22‐membered macrocycles containing triazole and bis(aryl ether) moieties. The compounds were prepared by a multicomponent approach from readily available commercial substrates. Notably, some of the compounds displayed interesting cytotoxicity against cancer (PC‐3) and breast (MCF‐7) cell lines, especially those bearing an aliphatic or a trifluoromethyl substituent on the N‐phenyl moiety (IC50<13 μm ). Additionally, some of the compounds were able to induce apoptosis relative to the solvent control; in particular, (Z)‐N‐cyclohexyl‐7‐oxo‐6‐[4‐(trifluoromethyl)phenyl]‐11H‐3,10‐dioxa‐6‐aza‐1(4,1)‐triazola‐4(1,3),9(1,4)‐dibenzenacyclotridecaphane‐5‐carboxamide ( 12 f ) was the most potent in this regard (22.7 % of apoptosis). 相似文献
3.
Jorge A. Marquez-Escalante Agustín Rascón-Chu Alma Campa-Mada Karla G. Martínez-Robinson Elizabeth Carvajal-Millan 《应用聚合物科学杂志》2020,137(5):48325
Feruloylated arabinoxylans (FAX) are gelling polysaccharides presenting antioxidant activity (AC) and potential application as delivery systems. The influence of carboxymethylation on the gelling capacity, rheological properties, and AC of FAX from wheat flour (FAX1) and maize distillers grains (FAX2) was analyzed. The degree of substitution of carboxymethyl groups was 0.27 and 1.77 for carboxymethylated FAX1 (CFAX1) and FAX2 (CFAX2), which presented a change in M n from 446 to 362 kDa and from 120 to 180 kDa, and a loss in FA content from 1.05 to traces and from 10.13 to 0.12, respectively, after carboxymethylation. G′ value at the end of rheological tests for FAX1 (71 Pa) and FAX2 (726 Pa) was higher than the corresponding G″ value. In contrast, G″ value for CFAX1 (0.35 Pa) and CFAX2 (0.03 Pa) was higher than the respective G′ value, indicating that they do no form gels. The AC increased in CFAX1 in relation to FAX1 from 4.49 to 8.30 mmol Trolox equivalent antioxidant capacity (TEAC) kg−1, respectively, while it decreased in CFAX2 with regard to FAX2 from 11.31 to 9.43 mmol TEAC kg−1, respectively. Carboxymethylation could be a path to design FAX derivatives offering alternative potential applications. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48325. 相似文献
4.
Photopolymerizable multifunctional monomers and their evaluation as reactive Bis‐GMA eluents 下载免费PDF全文
J. Abraham González‐López Carlos E. Cuevas‐Suárez Alma Antonia Pérez‐Mondragón M. Lydia Berlanga Duarte Ana M. Herrera‐González 《应用聚合物科学杂志》2018,135(19)
Bis‐GMA {2,2‐bis[4‐(2′‐hydroxy‐3′‐methacryloyloxy‐propoxy)‐phenyl]‐propane}, TEGDMA <2‐{2‐[2‐(2‐methylprop‐2‐enoyloxy)ethoxy]ethoxy}ethyl‐2‐methylprop‐2‐enoate>, and methyl methacrylate (MMA) are some of the most commonly used monomers in the field of restorative dentistry. These compounds are characterized by having one or two terminal double bonds. Besides the effort to synthesize new monomers, several problems still affect the clinical behavior of contemporary dental materials. In this work, two monomers with three terminal double bonds, 5A13DA and 5A13DMA, were synthesized. Both monomers were used to completely replace TEGDMA as reactive diluent of photopolymerizable dental resin composites containing Bis‐GMA. The effects of 5A13DA and 5A13DMA on flexural properties, double bond conversion, water sorption, solubility, and polymerization shrinkage were evaluated. In addition, both monomers were evaluated as crosslinking agents for methylmethacrylate, resulting in copolymers with enhanced thermal stability. The results obtained suggest that newly synthesized monomers are potential substitutes for TEGDMA in the formulation of dental composites, providing 50% lower volumetric shrinkage than the composite resin used as control and adequate mechanical properties. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46240. 相似文献
5.
Effect of montmorillonite clay addition on the morphological and physical properties of Jatropha curcas L. and Glycine max L. protein concentrate films 下载免费PDF全文
Alex Osorio‐Ruiz Javier Solorza‐Feria Bor‐Sen Chiou Delilah F. Wood Tina G. Williams Roberto J. Avena‐Bustillos Alma‐Leticia Martínez‐Ayala 《应用聚合物科学杂志》2017,134(7)
Protein concentrates from jatropha (JPC) and soy seeds (SPC) were obtained by solubilization and acid precipitation of proteins. JPC and SPC films were prepared by the casting method, using two different montmorillonite (MMT) clay concentrations and plasticized with glycerol. Film properties were evaluated by scanning electron microscopy, transmission electron microscopy, X‐ray diffraction (XRD), Fourier transform infrared spectroscopy, thermogravimetric analysis, tensile properties, water retention, and water vapor transmission rate (WVRT). Typical tactoid microcomposite structures were found to be heterogeneously dispersed in the films containing MMT. A small XRD peak was found in films with MMT. Slight improvements in thermal stability and tensile strength were observed in the films with MMT. Reductions in water retention and WVRT were obtained when MMT was added into the films. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44459. 相似文献
6.
Rodrigo Montoya Allan G. Ruiz-García Alma Ortiz-Ozuna Blanca Ramírez-Barat Juan Genesca 《工业材料与腐蚀》2021,72(7):1259-1269
The electrochemical interactions between aluminum alloy 7075 and low-carbon steels under gelled electrolytes were studied. Such electrolytes provided the opportunity to investigate both thick and thin electrolyte systems. The electrolyte was chemically modified to visually track the acidic fronts during the anodic reaction and the subsequent hydrolysis process. Two mathematical models were validated for both thick and ultrathin electrolytes. The acidification of thick electrolytes was extended some millimeters beyond the aluminum alloy surface, whereas the acidic front was localized next to the metallic joint using ultrathin electrolytes. The combination of both numerical and experimental results allows proving (and explaining why) that the acidification process is more aggressive under dilute than under concentrated electrolytes. 相似文献
7.
Alfredo Jurez-Saldivar Elizabeth Barbosa-Cabrera Edgar E. Lara-Ramírez Alma D. Paz-Gonzlez Ana V. Martínez-Vzquez Virgilio Bocanegra-García Isidro Palos Nuria E. Campillo Gildardo Rivera 《International journal of molecular sciences》2021,22(11)
Infectious diseases caused by intestinal protozoan, such as Entamoeba histolytica (E. histolytica) and Giardia lamblia (G. lamblia) are a worldwide public health issue. They affect more than 70 million people every year. They colonize intestines causing primarily diarrhea; nevertheless, these infections can lead to more serious complications. The treatment of choice, metronidazole, is in doubt due to adverse effects and resistance. Therefore, there is a need for new compounds against these parasites. In this work, a structure-based virtual screening of FDA-approved drugs was performed to identify compounds with antiprotozoal activity. The glycolytic enzyme triosephosphate isomerase, present in both E. histolytica and G. lamblia, was used as the drug target. The compounds with the best average docking score on both structures were selected for the in vitro evaluation. Three compounds, chlorhexidine, tolcapone, and imatinib, were capable of inhibit growth on G. lamblia trophozoites (0.05–4.935 μg/mL), while folic acid showed activity against E. histolytica (0.186 μg/mL) and G. lamblia (5.342 μg/mL). 相似文献
8.
Thomas J. Siller Alma Rosales John Haines Aaron Benally 《Canadian Metallurgical Quarterly》2009,135(3):102-108
The development of engineering students’ professional skills has gained considerable national attention from Accreditation Board for Engineering and Technology, the National Academy of Engineering, ASCE, and other constituents. There is little debate that these professional skills are necessary. Engineering programs have tried many approaches to develop these skills in the undergraduate programs. Colorado State University (CSU) has developed a new approach modeled on the type of professional development that occurs in the professional environment. This new Professional Learning Institute (PLI) provides students with a broad array of workshops, presentations, and experiential opportunities addressing the areas of cross cultural communication and teamwork, innovation, leadership, ethics, and public service. This program introduces students to the concept of professional development through required extracurricular activities, includes minimum requirements along with requirements to earn certificates in specialty areas for motivated students. The majority of offerings in the PLI are presented by leaders from the engineering profession who have teamed with CSU to provide high quality programs for our students. 相似文献
9.
Juan Torruco-Uco Luis Chel-Guerrero Alma Martínez-Ayala Gloria Dávila-Ortíz David Betancur-Ancona 《LWT》2009,(10):1597-1604
Phaseolus lunatus and Phaseolus vulgaris protein concentrates were hydrolyzed with the enzymes Alcalase® and Flavourzyme® at different reaction times, and the angiotensin-I converting enzyme (ACE-I) inhibitory activity, antioxidant properties and amino acid composition measured in the hydrolysates. With Alcalase®, the highest degree of hydrolysis (DH) in P. lunatus was 37.94% at 45 min, and in P. vulgaris was 49.48% at 30 min. With Flavourzyme®, the highest DH's were 22.03% and 26.05%, respectively, both at 90 min. ACE-I inhibitory activity in the Alcalase® hydrolysates was IC50 = 0.056 mg mL−1 for P. lunatus at 90 min, and IC50 = 0.061 mg mL−1 for P. vulgaris at 60 min. In the Flavourzyme® hydrolysates this activity was IC50 = 0.0069 mg mL−1 for P. lunatus at 90 min and IC50 = 0.127 mg mL−1 for P. vulgaris at 45 min. In SDS-PAGE, the hydrolysates exhibited low molecular weight bands. Antioxidant activity was 11.55 mmol L−1 TEAC mg−1 protein for P. lunatus with Flavourzyme® at 90 min and 10.09 mmol L−1 TEAC mg−1 protein for P. vulgaris with Alcalase® at 60 min. Amino acid composition exhibited high amino acid hydrophobic residues content. 相似文献
10.
René R. Colditz Joanna Acosta-Velázquez José Reyes Díaz Gallegos Alma Delia Vázquez Lule María Teresa Rodríguez-Zúñiga Pedro Maeda 《International journal of remote sensing》2013,34(20):6426-6445
Change detection is one of the primary applications of remote-sensing data, and many techniques have been developed during the past three decades. Although frequently criticized and despite many alternatives, due to its simplicity and intuitive manner, post-classification change detection still remains one of the most applied techniques. Many studies in the field of change detection analysis acknowledge, for instance, the impact of misregistration, inconsistencies in classification schemes or differences in methods for image interpretation. However, there are additional, rarely studied influences that can cause large errors in change detection results, including integrating multi-resolution data, the adjacency effect and the minimum mapping units (MMUs) that are applied to the classification before change detection. This study demonstrates these effects for the complex land cover of the Alvarado mangrove area at the Mexican Gulf Coast, employing 10 m Système Pour l'Observation de la Terre 5 (SPOT-5) high geometric resolution (HRG)‐based and 57 m Landsat Multispectral Scanner (MSS) classifications. As a baseline, the proportion of the fine spatial resolution classes within the coarse spatial resolution cells were derived, from which proportional change matrices were computed. The analysis employs difference measures to compare change matrices and proportional maps. The impact of various tested resampling functions was negligible if coarse resolution data were refined. For coarsening fine spatial resolution data, change matrix comparison was comparatively small but yielded differences of approximately 20% in spatially explicit measures. Incorrect positional alignment indicated differences of up to 5% in the change matrix for a misregistration of 100 m and even higher spatially explicit differences (28%). The discrepancies due to the adjacency effect were rather low. MMUs of 25 ha resulted in differences of up to 36% in the change matrix. The magnitude of the discrepancies of all studied effects depends on the class diversity in the map, and some can also be related to the difference in spatial resolution. 相似文献