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Background

Obesity and diabetes mellitus (DM) are public health concerns in Mexico of top-level priority due to their high prevalence and their growth rate in recent decades. The accumulation of adipose tissue leads to an unbalanced release of pro-oxidant factors, which causes cellular damage and favors the development of comorbidities. Recent evidence suggests that oxidative stress also promotes the accumulation of adipose tissue and the development of insulin resistance. The objective of this study is to evaluate the association between usual intake of antioxidant nutrients, specifically vitamins A, C, E and magnesium with body mass index (BMI), waist circumference (WC) and serum glucose concentrations in a representative sample of Mexican adults.

Methodology

We analyzed data on diet, BMI, WC and serum glucose from the Mexican National Health and Nutrition Survey 2012. Analysis included 20- to 65-year-old adults without a known diagnosis of DM (n?=?1573). Dietary information was obtained using the five-step multiple-pass method developed by the United States Department of Agriculture and adapted to the Mexican context. Nutrient usual intake distributions were estimated using the Iowa State University method, through the “Software for Intake Distribution Estimation” (PC-Side) v.1.02. Associations were analyzed using multivariate regression models.

Results

Higher dietary magnesium intake was associated with lower markers of adiposity, so that an increase in 10?mg per 1000?kcal/day of magnesium was associated with an average decrease in BMI of 0.72% (95% CI: -1.36, ??0.08) and 0.49?cm (95% CI: -0.92, ??0.07) of WC. Additionally, in women with normal glucose concentrations, an increase in magnesium intake was associated with an average decrease in serum glucose by 0.59% (95% CI: -1.08, ??0.09).

Conclusion

The results suggest that magnesium intake is associated with lower BMI, WC and serum glucose in Mexican population. However, more studies are required to elucidate the nature of this association.
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Xyloglucan is a polysaccharide isolated from chia seed gum (Salvia hispanica L.) and can act as a soluble fiber. In this investigation, several porous hydrogels were prepared from mixtures of chitosan and xyloglucan. To characterize these biomaterials, their mechanical, hydrophilic, structural, and morphological properties were measured, as well as their biodegradability and antimicrobial activity. The pore sizes of the porous hydrogels were 32.8–101.6 μm, and their water retention capacity is proportional to the added amount of xyloglucan. Dynamic degradation of the porous hydrogels with lysozymes showed progressive weight loss during the 14 days of testing. The mechanical properties improved slightly after the addition of xyloglucan. All of these results indicate that the incorporation of vegetable-derived polymers such as xyloglucan improves the properties of chitosan without affecting its antimicrobial capacity. Thus, biomaterials based on chitosan and xyloglucan are a promising option for the design of hydrogel wound dressings for medical applications. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47342.  相似文献   
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In this article, an improved synthesis strategy of the potent anticancer compound 4,7-dichloro-2-quinolinemethanol (QM) and its acrylate ester 4,7-dichloro-2-quinolinemethylacrylate (AQM) are described. AQM is copolymerized using free-radical polymerization with N-vinyl-2-pyrrolidone (VP) and the copolymers obtained from different molar ratios of monomers are subjected to nanoprecipitation to produce suspensions of nanoparticles (NPs) in phosphate buffered saline (PBS). The smallest and stable NPs are prepared with the AQM-VP copolymers 45:55 and 40:60 (118.9 and 128.7 nm in diameter, respectively) at 1 mg mL−1, and along with AQM and QM, are evaluated for their cytotoxic activity on MDA-MB-453 breast carcinoma cells using MTT bioassay. AQM and QM are highly cytotoxic (IC50: 19 and 41 μM, respectively); however, the NPs are not cytotoxic in the range of the assayed concentrations. These results contribute to the search for new polymeric NPs with potential application as QM delivery systems for the treatment of cancer or other diseases treatable with QM. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47545.  相似文献   
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One of the earliest synthetic antimalarial drugs, quinacrine, was recently reported as interesting for the treatment of acute myeloid leukemia. Inspired by this and similar findings, we evaluated a set of quinacrine analogues against gastric (MKN‐28), colon (Caco‐2), and breast (MFC‐7) cancer cell lines and one normal human fibroblast cell line (HFF‐1). All the compounds, previously developed by us as dual‐stage antimalarial leads, displayed antiproliferative activity, and one of the set stood out as selective toward the gastric cancer cell line, MKN‐28. Interestingly, this compound was transported across an in vitro MKN‐28 model cell line in low amounts, and approximately 80 % was trapped inside those cells. Nuclear targeting of the same compound and its interactions with calf thymus DNA were assessed through combined fluorescence microscopy, spectroscopy, and calorimetry studies, which provided evidence for the compound's ability to reach the nucleus and to interact with DNA.  相似文献   
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