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Introduction: There are multiple mechanisms by which HbA1c values can be altered in chronic kidney disease (CKD), which limits its usefulness as a strategy to assess glycemic control in this population. Methods: Concordance and agreement study between two diagnostic tests: HbA1c and glucose management indicator (GMI) measured by intermittently scanned continuous glucose monitoring (isCGM), based in a prospective cohort of patients with diabetes, CKD (glomerular filtration rate between 15 and 60 ml/min/1.73 m²), and anemia. The isCGM was performed for 3 months, and the GMI was compared with the HbA1c levels taken at the end of isCGM. Agreement was evaluated using Bland-Altman graph analysis and Lin's concordance correlation coefficient (CCC). The concordance of the measures with good glycemic control (<7%) was also evaluated. Results: A total of 74 patients were enrolled (median age 68.5 years, 51.3% female, 64.9% with CKD stage 3, hemoglobin 11.1 ± 1.2 g/l). The Bland-Altman analysis shows a mean difference between GMI and HbA1c of 0.757 ± 0.687% (95% limits of agreement: -0.590 and 2.105). Difference was greater as the values of GMI and HbA1c increased. The agreement was poor [CCC 0.477; 95% confidence interval (CI): 0.360-0.594], as well as the concordance of values with good glycemic control according to GMI versus HbA1c (67.5% versus 29.7%, p < 0.001) (Kappa 0.2430; 95% CI: 0.16-0.32). Conclusion: The HbA1c overestimates the GMI values with highly variable ranges of difference, which prevents a precise correction factor. isCGM probably is a safer option for monitoring and decision-making in this population, especially in patients treated with insulin where the risk of hypoglycemia is greater.

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Knowledge of the 10B microdistribution is of great relevance in BNCT studies. Since 10B concentration assesment through neutron autoradiography depends on the correct quantification of tracks in a nuclear track detector, image acquisition and processing conditions should be controlled and verified, in order to obtain accurate results to be applied in the frame of BNCT. With this aim, an image verification process was proposed, based on parameters extracted from the quantified nuclear tracks. Track characterization was performed by selecting a set of morphological and pixel-intensity uniformity parameters from the quantified objects (area, diameter, roundness, aspect ratio, heterogeneity and clumpiness). Their distributions were studied, leading to the observation of varying behaviours in images generated by different samples and acquisition conditions. The distributions corresponding to samples coming from the BNC reaction showed similar attributes in each analyzed parameter, proving to be robust to the experimental process, but sensitive to light and focus conditions. Considering those observations, a manual feature extraction was performed as a pre-processing step. A Support Vector Machine (SVM) and a fully dense Neural Network (NN) were optimized, trained, and tested. The final performance metrics were similar for both models: 93%-93% for the SVM, vs 94%-95% for the NN in accuracy and precision respectively. Based on the distribution of the predicted class probabilities, the latter had a better capacity to reject inadequate images, so the NN was selected to perform the image verification step prior to quantification. The trained NN was able to correctly classify the images regardless of their track density. The exhaustive characterization of the nuclear tracks provided new knowledge related to the autoradiographic images generation. The inclusion of machine learning in the analysis workflow proves to optimize the boron determination process and paves the way for further applications in the field of boron imaging.

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Mucopolysaccharidoses (MPSs) are a heterogeneous group of diseases that have in common the accumulation of glycosaminoglycans (mucopolysaccharides) within the lysosome. The diseases are caused by a deficiency of the enzyme α-L-iduronidase which is responsible for the degradation of glycosaminoglycans (GAGs or mucopolysaccharides). More than 100 mutations in the gene have been reported, resulting in marked clinical/response variability. MPSs usually present as multisystem and progressive clinical disorders which affect psychomotor and cardiovascular development, the cornea and the musculoskeletal system. Seven phenotypically distinct diseases have been described, and MPS type I (MPS-I) is divided into three clinical forms: severe (Hurler syndrome), intermediate (Hurler-Scheie syndrome) or mild (Scheie syndrome). For the treatment of MPS-I, Enzyme Replacement Therapy (ERT) with α-L-iduronidase and Hematopoietic Stem Cells Transplantation (HSCT), separately or in combination, have produced clinical improvement, especially with regards cardiovascular symptoms and psychomotor development. This article presents the long-term (more than seven years) follow-up of monochorionic, diamniotic twins who were diagnosed with MPS-I at an early stage, and treated with ERT (from age 10 months) plus HSCT (from age 18 months). Overall, the treatment has facilitated stable development with an overall good response and better control of symptoms associated with MPS-I.

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In this work it is shown a precise way to optimize the heat generation in high viscosity magnetic colloids, by adjusting the Néel relaxation time in core/shell bimagnetic nanoparticles, for magnetic fluid hyperthermia (MFH) applications. To pursue this goal, Fe3O4/Zn x Co1-x Fe2O4 core/shell nanoparticles were synthesized with 8.5 nm mean core diameter, encapsulated in a shell of ∼1.1 nm of thickness, where the Zn atomic ratio (Zn/(Zn + Co) at%) changes from 33 to 68 at%. The magnetic measurements are consistent with a rigid interface coupling between the core and shell phases, where the effective magnetic anisotropy systematically decreases when the Zn concentration increases, without a significant change of the saturation magnetization. Experiments of MFH of 0.1 wt% of these particles dispersed in water, in Dulbecco modified Eagles minimal essential medium, and a high viscosity butter oil, result in a large specific loss power (SLP), up to 150 W g-1, when the experiments are performed at 571 kHz and 200 Oe. The SLP was optimized adjusting the shell composition, showing a maximum for intermediate Zn concentration. This study shows a way to maximize the heat generation in viscous media like cytosol, for those biomedical applications that require smaller particle sizes.

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In this work it is shown a precise way to optimize the heat generation in high viscosity magnetic colloids, by adjusting the Néel relaxation time in core/shell bimagnetic nanoparticles, for Magnetic Fluid Hyperthermia applications. To pursue this goal, Fe3O4/ZnxCo1-xFe2O4 core/shell nanoparticles were synthesized with 8.5 nm mean core diameter, encapsulated in a shell of ~1.1 nm of thickness, where the Zn atomic ratio (Zn/(Zn+Co) at%) changes from 33 at% to 68 at%. The magnetic measurements are consistent with a rigid interface coupling between the core and shell phases, where the effective magnetic anisotropy systematically decreases when the Zn concentration increases, without a significant change of the saturation magnetization. Experiments of magnetic fluid hyperthermia of 0.1 wt% of these particles dispersed in water, DMEM (Dulbecco modified Eagles minimal essential medium) and a high viscosity butter oil, result in a large specific loss power (SLP), up to 150 W/g, when the experiments are performed at 571 kHz and 200 Oe. The SLP was optimized adjusting the shell composition, showing a maximum for intermediate Zn concentration. This study shows a way to maximize the heat generation in viscous media like cytosol, for those biomedical applications that requiere smaller particle sizes .

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Alternaria dauci is the causal agent of Alternaria leaf blight (ALB) in carrot (Daucus carota) crops around the world. However, to date, A. dauci has received limited attention in its production of phytotoxic metabolites. In this investigation, the bioassay-guided isolation of the extract from liquid cultures of A. dauci resulted in the isolation of two metabolites identified as α-acetylorcinol (1) and p-hydroxybenzoic acid (2), based on their spectroscopic data and results from chemical correlation reactions. Testing of both metabolites in different assays showed an important phytotoxic activity for p-hydroxybenzoic acid (2) when tested in the leaf-spot assay on parsley (Petroselinum crispum), in the leaf infiltration assay on tobacco (Nicotiana alata) and marigold (Tagetes erecta), and in the immersion assay on parsley and parsnip (Pastinaca sativa) leaves. Quantification of the two metabolites in the crude extract of A. dauci kept at different times showed that p-hydroxybenzoic acid (2) is one of the first metabolites to be synthesized by the pathogen, suggesting that this salicylic acid derivative could play an important role in the pathogenicity of the fungus.

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The Yucatan Peninsula possesses a unique climate, geology, landscape, and biota that includes a distinct flora of over 2300 species; of these, close to 800 plants are used in what is known as Mayan traditional medicine, and about 170 are listed as native or endemic. Even though the flora of the Yucatan peninsula has been widely studied by naturalists and biologists, to date, phytochemical and pharmacological knowledge of most of the plants, including the medicinal plants, is limited. Presently, phytochemical studies carried out on plants from the Yucatecan flora have resulted in the identification of a wide variety of natural products that include flavonoids, terpenoids, polyketides, and phenolics with cytotoxic, antiprotozoal, antibacterial, anti-inflammatory, analgesic, antioxidant, and antifungal activities. This review describes the main findings in over 20 years (1992 to 2018) of exploring the natural product diversity of the Yucatecan flora.

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Se analizan tendencias recientes de investigación en comunicación publicadas en revistas de comunicación latinoamericanas más visibles en bases de datos de referencia y citación. La revisión se centra en los artículos de investigación publicados entre 2013 y 2017 en las nueve revistas latinoamericanas de comunicación incluidas en Scopus. La metodología se basa en la consulta de bases de datos, su sistematización a través de gestores bibliográficos y el análisis de contenido cualitativo de los textos recopilados, apoyado con el software de QDA NVIVO11. Se recopilan 167 artículos que abordan temáticas de educomunicación, alfabetización mediática y narrativas transmedia. Predomina la autoría individual y la afiliación a un solo país e institución, entre los cuales destacan Brasil y España. En relación con el contenido, predomina un enfoque temático sobre los medios y los entornos digitales y un abordaje cualitativo de las investigaciones.

This study analyzed recent research trends in communication research published in nine leading communication journals in Latin America. A literature review of scientific articles published between 2013 and 2017 was conducted using the Scopus database. A database query was run, together with the systematization of data using bibliographic management software and qualitative content analysis of selective texts using the QDA software NVivo 11. A total of 167 articles addressing the themes educommunication, media literacy, and transmedia narrative were analyzed. The majority of articles were written by individual authors belonging to a single institution and country, with emphasis on Brazil and Spain. With respect to content, the predominant themes were media and digital environments and the majority of studies used a qualitative approach.

Analisam-se as tendências recentes de pesquisa em comunicação publicadas nas nove revistas de comunicação mais significativas da América Latina. A pesquisa se centra na revisão dos artigos científicos publicados entre 2013 e 2017 em Scopus. A metodologia se baseia na consulta de bases de dados, sua sistematização por meio de gestores bibliográficos e a analise do conteúdo qualitativo dos textos selecionados, com o uso do software QDA NVIVO11. Estudam-se 167 artigos que abrangem temáticas de educomunicação, alfabetização midiática e narrativas transmídia. Pode-se identificar o predomínio da autoria individual, assim como a filiação a uma só instituição e a um só país, com destaque para Brasil e Espanha. A respeito do conteúdo, predomina o foco temático sobre mídia e os entornos digitais, assim como uma abordagem qualitativa das pesquisas.

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Agricultural practices affect the bacterial community structure, but how they determine the response of the bacterial community to drought, is still largely unknown. Conventional cultivated soil, i.e., inorganic fertilization, tillage, crop residue removal and maize (Zea mays L.) monoculture, and traditional organic farmed soil "milpa," i.e., minimum tillage, rotation of maize, pumpkin (Cucurbita sp.) and beans (Phaseolus vulgaris L.) and organic fertilization were sampled. Both soils from the central highlands of Mexico were characterized and incubated aerobically at 5% field capacity (5%FC) and 100% field capacity (FC) for 45 days, while the C and N mineralization, enzyme activity and the bacterial community structure were monitored. After applying the different agricultural practices 3 years, the organic C content was 1.8-times larger in the milpa than in the conventional cultivated soil, the microbial biomass C 1.3-times, and C and N mineralization 2.0-times (mean for soil incubated at 5%FC and FC). The dehydrogenase, activity was significantly higher in the conventional cultivated soil than in the milpa soil when incubated at 5%FC, but not when incubated at FC. The relative abundance of Gemmatimonadetes was larger in the conventional cultivated soil than in the milpa soil in soil both at 5%FC and FC, while that of Bacteroidetes showed an opposite trend. The relative abundance of other groups, such as Nitrospirae and Proteobacteria, was affected by cultivation technique, but controlled by soil water content. The relative abundance of other groups, e.g., FBP, Gemmatimonadetes and Proteobacteria, was affected by water content, but the effect depended on agricultural practice. For soil incubated at FC, the xenobiotics biodegradation and metabolism related functions were higher in the milpa soil than in the conventional cultivated soil, and carbohydrate metabolism showed an opposite trend. It was found that agricultural practices and soil water content had a strong effect on soil characteristics, C and N mineralization, enzyme activity, and the bacterial community structure and its functionality. Decreases or increases in the relative abundance of bacterial groups when the soil water content decreased, i.e., from FC to 5%FC, was defined often by the cultivation technique, and the larger organic matter content in the milpa soil did not prevent large changes in the bacterial community structure when the soil was dried.

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ABSTRACT Calea urticifolia (Mill.) DC., Asteraceae, is a native plant of the Yucatan Peninsula used in traditional medicine to treat inflammation and pain. The bioassay-guided purification of the ethanol root extract allowed the isolation of the main bioactive metabolites, which were identified as an inseparable mixture of thymol (1) and 3-methyl-4-isopropylphenol (2), together with 3,4-O-dicaffeoylquinic acid methyl ester (3), 3,4-O-dicaffeoyl-epi-quinic acid methyl ester (4), 3,5-O-dicaffeoyl-epi-quinic acid methyl ester (5) and 3,5-O-dicaffeoylquinic acid (6). The results showed that the analgesic activity detected in the root extract of C. urticifolia could be attributed mainly to the mixture of 1 and 2 and to the novel 3,4-O-dicaffeoyl-epi-quinic acid methyl ester (4). Alternatively, the similarity on the antiinflammatory and antioxidant activities of the dicaffeoylquinic acid derivatives 3-5 suggests that the former might be related to their ability as radical scavengers.