RESUMO

One of the main causes of food spoilage is the lipid oxidation of its components, which generates the loss of nutrients and color, together with the invasion of pathogenic microorganisms. In order to minimize these effects, active packaging has played an important role in preservation in recent years. Therefore, in the present study, an active packaging film was developed using polylactic acid (PLA) and silicon dioxide (SiO2) nanoparticles (NPs) (0.1% w/w) chemically modified with cinnamon essential oil (CEO). For the modification of the NPs, two methods (M1 and M2) were tested, and their effects on the chemical, mechanical, and physical properties of the polymer matrix were evaluated. The results showed that CEO conferred to SiO2 NPs had a high percentage of 2,2-diphenyl-l-picrylhydrazyl (DPPH) free radical inhibition (>70%), cell viability (>80%), and strong inhibition to E. coli, at 45 and 11 µg/mL for M1 and M2, respectively, and thermal stability. Films were prepared with these NPs, and characterizations and evaluations on apple storage were performed for 21 days. The results show that the films with pristine SiO2 improved tensile strength (28.06 MPa), as well as Young's modulus (0.368 MPa) since PLA films only presented values of 27.06 MPa and 0.324 MPa, respectively; however, films with modified NPs decreased tensile strength values (26.22 and 25.13 MPa), but increased elongation at break (from 5.05% to 10.32-8.32%). The water solubility decreased from 15% to 6-8% for the films with NPs, as well as the contact angle, from 90.21° to 73° for the M2 film. The water vapor permeability increased for the M2 film, presenting a value of 9.50 × 10-8 g Pa-1 h-1 m-2. FTIR analysis indicated that the addition of NPs with and without CEO did not modify the molecular structure of pure PLA; however, DSC analysis indicated that the crystallinity of the films was improved. The packaging prepared with M1 (without Tween 80) showed good results at the end of storage: lower values in color difference (5.59), organic acid degradation (0.042), weight loss (24.24%), and pH (4.02), making CEO-SiO2 a good component to produce active packaging.

RESUMO

COVID-19 has drawn worldwide attention to the need for personal protective equipment. Face masks can be transformed from passive filters into active protection. For this purpose, it is sufficient to apply materials with oligodynamic effect to the fabric of the masks, which makes it possible to destroy infectious agents that have fallen on the mask with aerosol droplets from the air stream. Zeolites themselves are not oligodynamic materials, but can serve as carriers for nanoparticles of metals and/or compounds of silver, zinc, copper, and other materials with biocidal properties. Such a method, when the particles are immobilized on the surface of the substrate, will increase the lifetime of the active oligodynamic material. In this work, we present the functionalization of textile materials with zeolites to obtain active personal protective equipment with an extended service life. This is done with the aim to extend the synthesis of zeolitic materials to polymeric fabrics beyond cotton. The samples were characterized using XRD, SEM, and UV-Vis spectroscopy. Data of physicochemical studies of the obtained hybrid materials (fabrics with crystals grown on fibers) will be presented, with a focus on the effect of fabrics in the growth process of zeolites.

RESUMO

Our objective was to determine the association between the methylenetetrahydrofolate reductase polymorphisms (C677T and A1298C) and the risk of developing acute lymphoblastic leukemia (ALL), chronic myeloid leukemia (CML), acute myeloid leukemia (AML), and multiple myelomas (MM) in Latinos. PubMed, SCOPUS, EBSCO, LILACS, and other Latin-specific databases were searched for case-control studies that investigated the association between these polymorphisms and hematologic malignancies until November 2017. Genotype distributions were extracted and either fixed-effects or random-effects models were used to calculate the pooled crude odds ratios (ORs) for the heterozygous, homozygous, dominant, recessive, and allelic genetic models. No publication bias was detected by the Begg-Mazumdar's test and Egger's test. From 290 publications, we identified 15 studies on the C677T polymorphism and 13 studies on the A1298C polymorphism. We observed a significant decrease in risk for the C677T polymorphism (OR range=0.54-0.75, p<0.01) and a significant increase in risk for the A1298C polymorphism (OR range=1.28-2.52, p<0.05) in developing ALL for all genetic models. No associations were determined for CML, AML, or MM for either polymorphism. This meta-analysis demonstrated that the A1298C polymorphism was associated with an increased risk of developing ALL, whereas the C677T polymorphism was associated with a decreased risk (protective factor) in the Latino population.

RESUMO

Mayan community forest reserves (MCFR) play an important role in agricultural landscapes in Mexico, as they provide forest products and a broad variety of benefits that contribute to improving local people's livelihoods. Nevertheless, academia has generally considered conservation and use of forest resources to be incompatible. We describe the spatial configuration of MCFR, evaluate floristic and structural characteristics of woody vegetation present in selected reserves, and identify social norms that govern use and conservation of MCFR. These reserves largely consist of mature vegetation (80% of total cover); their plant structure is similar to that of the surrounding tropical sub-deciduous forest; and they house a large number of endemic species. The MCFR studied contain a total of 146 tree species and cover 11% of the study area, which includes at least 140 villages in the north-central part of the Yucatan Peninsula. These reserves are collectively managed and conserved by Mayan peasants in the interest of the common good. The communities in our study area combine conservation and use of forest resources, and we recommend that in public policy, government agencies and NGOs incorporate MCFR as a model of biological conservation and sustainable natural resource use, taking into account traditional knowledge and local norms that allow these reserves to function in a sustainable manner.

Assuntos

Conservação dos Recursos Naturais , Árvores , Biodiversidade , Florestas , México

RESUMO

BACKGROUND: Previous meta-analyses have shown an ethnic dependency of the C677T and the A1298C methylenetetrahydrofolate reductase (MTHFR) polymorphisms, with no focus on the Latino population. For Latinos, many studies have examined these polymorphisms and breast cancer susceptibility, yielding no concise result. Therefore, we undertook this meta-analysis to determine the effect these polymorphisms have on breast cancer risk for Latinos. METHODS: PubMed, EBSCO, LILACS, Scopus, and Latin American-specific databases were searched for studies exploring the association between the MTHFR polymorphisms and breast cancer susceptibility in Latinos until January 2019. Genotype distributions were extracted and, depending on the level heterogeneity determined by the ψ2-based Q test and the I2 test, fixed-effects or random-effects models were used to calculate pooled odds ratios (ORs) with 95% confidence intervals (95% CIs) for the heterozygous, homozygous, dominant, recessive, and allelic genetic models. No publication bias was detected by the Begg-Mazumdar's test and Egger's test. RESULTS: Of the 280 retrieved publications, 9 studies were included: 9 for the C677T polymorphism and 5 for the A1298C polymorphism. For the C677T polymorphism, there was an elevated risk for the homozygous (OR 1.42, 95% CI 1.05-1.92), the dominant (OR 1.16, 95% CI 1.02-1.31), the recessive (OR 1.33, 95% CI 1.01-1.75), and the allelic model (OR 1.17, 95% CI 1.03-1.33, p < 0.01). No association between the A1298C polymorphism and the risk to develop breast cancer was determined. CONCLUSION: The results indicated that, for Latinos, the C677T polymorphism is associated with a significant risk for developing breast cancer, whereas the A1289C polymorphism does not.

Assuntos

Neoplasias da Mama/etnologia , Neoplasias da Mama/enzimologia , Predisposição Genética para Doença , Hispânico ou Latino/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo de Nucleotídeo Único , Alelos , Carcinogênese/genética , Éxons/genética , Feminino , Heterogeneidade Genética , Genótipo , Humanos , Metilenotetra-Hidrofolato Redutase (NADPH2)/metabolismo , Razão de Chances , Viés de Publicação , Risco

RESUMO

Resumen OBJETIVO: Exponer los desenlaces de dos técnicas de sutura hemostática uterina para controlar la hemorragia obstétrica. MATERIALES Y MÉTODOS: Estudio prospectivo, observacional y longitudinal, llevado a cabo en tres unidades hospitalarias de Guanajuato, México, del 1 de enero al 30 de noviembre de 2018. Se incluyeron pacientes con hemorragia transcesárea y posparto. En las primeras se aplicó la técnica de B-Lynch y en las segundas la de Hayman. Se analizaron las variables: 1) cantidad de hemorragia antes y después de aplicar la sutura, 2) tiempo del procedimiento, 3) concentración de hemoglobina al ingreso a la unidad de atención, 1 hora después de la hemorragia y 24 horas posteriores a la intervención quirúrgica, 4) desenlace de las técnicas y 5) complicaciones. Para el análisis de los datos se utilizó el programa SPSS versión 22 para Windows. RESULTADOS: Se registraron 34 pacientes: 26 con aplicación de la técnica de sutura B-Lynch y 8 con la técnica de Hayman. La pérdida sanguínea después de la aplicación de las técnicas fue menor (p < 0.001). El tiempo entre el diagnóstico de hemorragia y la aplicación de la sutura fue de 11.5 ± 5.9 minutos. La concentración de hemoglobina al ingreso al hospital y 1 h posterior a la hemorragia fue significativamente menor (p < 0.01) versus 24 h después (p < 0.05) 30 de 34 pacientes tuvieron reacción favorable al tratamiento quirúrgico. Cuatro mujeres requirieron procedimientos adicionales para el control de la hemorragia. No se reportaron complicaciones ni muertes maternas asociadas con las técnicas de sutura. CONCLUSIONES: Las técnicas de sutura uterina representan un procedimiento útil, rápido y sin complicaciones para el control de la hemorragia obstétrica.

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Abstract OBJECTIVE: To present the results obtained with two techniques of uterine hemostatic sutures for the control of obstetric hemorrhage. MATERIALS AND METHODS: Prospective, observational, longitudinal study in three hospital units of the 1st. from January to November 30, 2018. Thirty-four patients with postpartum and transcesarean hemorrhage were included. The postpartum patients underwent Hayman technique and the B-Lynch technique. The following were analyzed: 1) amount of hemorrhage before and after the sutures, 2) time between diagnosis and placement, 3) hemoglobin levels at admission to the care unit, 1 hour after the hemorrhage and 24 hours after treatment, 4) results with the two techniques and 5) complications. Statistical analysis of all these variables was performed with SPSS, 22 version. RESULTS: A total of 34 patients were registered: 26 sutures performed with B-Lynch technique and 8 with Hayman technique. The amount of bleeding after the application was lower (p <0.001). The time between diagnosis of bleeding and placement was 11.5 + 5.9 minutes. The hemoglobin levels at admission to the hospital and one hour after the hemorrhage were significantly lower (p <0.01) and 24 hours later (p <0.05). In 30/34 of cases, a favorable response to surgical treatment was achieved. In four cases, another procedure was required to control bleeding. There were no complications with the use of sutures or maternal deaths. CONCLUSIONS: The use of uterine sutures was a useful, fast and uncomplicated therapy for the control of obstetric hemorrhage.