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BACKGROUND: Polymeric electrospun mats have been used as scaffolds in tissue engineering for the development of novel materials due to its characteristics. The usage of synthetic materials has gone in decline due to environmental problems associated with their synthesis and waste disposal. Biomaterials such as biopolymers have been used recently due to good compatibility on biological applications and sustainability. OBJECTIVE: The purpose of this work is to obtain novel materials based on synthetic and natural polymers for applications on tissue engineering. METHODS: Aloe vera mucilage was obtained, chemically characterized, and used as an active compound contained in electrospun mats. Polymeric scaffolds were obtained in single, coaxial and tri-layer structures, characterized and evaluated in cell culture. RESULTS: Mucilage loaded electrospun fibers showed good compatibility due to formation of hydrogen bonds between polymers and biomolecules from its structure, evidenced by FTIR spectra and thermal properties. Cell viability test showed that most of the obtained mats result on viability higher than 75%, resulting in nontoxic materials, ready to be used on scaffolding applications. CONCLUSION: Mucilage containing fibers resulted on materials with potential use on scaffolding applications due to their mechanical performance and cell viability results.

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In this study, the functionality of an elastomer composite material containing polypyrrole (PPy) as a stress sensor was evaluated. The material was prepared using the swelling method by diffusing the pyrrole monomer into the elastomer before polymerization. To achieve adequate diffusion, organic solvents with affinity for the elastomer were used. The resulting materials were characterized by scanning electron microscopy (SEM), surface electrical resistance, and thermal and mechanical properties for application as a stress sensor. The simultaneous change in electrical resistance and tension stress was measured using a digital multimeter with electrodes connected to the jaws of a universal mechanical testing machine. The influence of stress cycles on the piezoresistivity of the composite materials was investigated. The obtained PPy/NBR composite presented a good combination of electrical conductivity and mechanical properties. The strain at break remained with mild variation after coating with PPy.

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Photothermal nanocomposite hydrogels are promising materials for remotely triggering drug delivery by near-infrared (NIR) radiation stimuli. In this work, a novel hydrogel based on poly(vinyl alcohol), poly(vinyl methyl ether-alt-maleic acid), poly(vinyl methyl ether), and functionalized multiwalled carbon nanotubes (MWCNT-f) was prepared by the freeze/thaw method. A comparative characterization of materials (with and without MWCNT-f) was carried out by infrared spectroscopy, differential scanning calorimetry, scanning electron microscopy, mechanical assays, swelling kinetics measurements, and photothermal analysis under NIR irradiation. Hydrophilic chemotherapeutic 5-fluorouracil (5-FU) and hydrophobic ibuprofen drugs were independently loaded into hydrogels, and the drug release profiles were obtained under passive and NIR-irradiation conditions. The concentration-dependent cytotoxicity of materials was studied in vitro using noncancerous cells and cancer cells. Notable changes in the microstructure and physicochemical properties of hydrogels were observed by adding a low content (0.2 wt %) of MWCNT-f. The cumulative release amounts of 5-FU and ibuprofen from the hydrogel containing MWCNT-f were significantly increased by 21 and 39%, respectively, through the application of short-term NIR irradiation pulses. Appropriate concentrations of the nanocomposite hydrogel loaded with 5-FU produced cytotoxicity in cancer cells without affecting noncancerous cells. The overall properties of the MWCNT-f-containing hydrogel and its photothermal behavior make it an attractive material to promote the release of hydrophilic and hydrophobic drugs, depending on the treatment requirements.

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In Brazil, current information about breastfeeding indicators among indigenous living in the urban areas is lacking. This article describes the duration of exclusive breastfeeding and its associations with mother and child characteristics in a cohort of Terena infants. The study enrolled infants born between June 2017 to July 2018 (n = 42) and living in villages of the urban area of Campo Grande, Mato Grosso do Sul State, Brazil. Information was collected in four time-points. Variables on maternal sociodemographics and on maternal and child health characteristics were collected, respectively, during the antenatal and the first-month interviews. Variables on breastfeeding practices and bottle use were collected during the first-, six- and 12-month interviews. Associations were examined using Wilcoxon, Kruskal-Wallis, Pearson's chi-square, and Fisher's exact tests. The prevalence of exclusive breastfeeding duration to the ages of three and six months were, respectively, 50% and 11.9%. Compared to infants never introduced to bottles during the first three months of life, those bottle-fed had lower median duration of exclusive breastfeeding (15 versus 150 days) and lower prevalence of exclusive breastfeeding duration to the age of three months (22.7% versus 80%). Most Terena infants fell short of meeting the international recommended duration of exclusive breastfeeding until six months of age and suggested the negative impact of bottle use in the duration of exclusive breastfeeding.

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Abstract In Brazil, current information about breastfeeding indicators among indigenous living in the urban areas is lacking. This article describes the duration of exclusive breastfeeding and its associations with mother and child characteristics in a cohort of Terena infants. The study enrolled infants born between June 2017 to July 2018 (n = 42) and living in villages of the urban area of Campo Grande, Mato Grosso do Sul State, Brazil. Information was collected in four time-points. Variables on maternal sociodemographics and on maternal and child health characteristics were collected, respectively, during the antenatal and the first-month interviews. Variables on breastfeeding practices and bottle use were collected during the first-, six- and 12-month interviews. Associations were examined using Wilcoxon, Kruskal-Wallis, Pearson's chi-square, and Fisher's exact tests. The prevalence of exclusive breastfeeding duration to the ages of three and six months were, respectively, 50% and 11.9%. Compared to infants never introduced to bottles during the first three months of life, those bottle-fed had lower median duration of exclusive breastfeeding (15 versus 150 days) and lower prevalence of exclusive breastfeeding duration to the age of three months (22.7% versus 80%). Most Terena infants fell short of meeting the international recommended duration of exclusive breastfeeding until six months of age and suggested the negative impact of bottle use in the duration of exclusive breastfeeding.

Resumo No Brasil, não há informações atuais sobre indicadores de aleitamento materno entre indígenas residentes em áreas urbanas. O objetivo deste estudo foi descrever a duração do aleitamento materno exclusivo e suas associações com características maternas e infantis em uma coorte de lactentes Terena. O estudo incluiu crianças nascidas de junho de 2017 a julho de 2018 (n = 42) e residentes em povoados da zona urbana de Campo Grande, Mato Grosso do Sul, Brasil. As informações foram coletadas em quatro momentos. Variáveis sociodemográficas maternas e características de saúde materno-infantil foram coletadas durante o pré-natal e o primeiro mês de entrevistas, respectivamente. As variáveis sobre práticas de amamentação e uso de mamadeira foram coletadas durante as entrevistas realizadas no primeiro mês, seis meses e 12 meses. As associações foram examinadas pelos testes de Wilcoxon, Kruskal-Wallis, qui-quadrado de Pearson e exato de Fisher. As prevalências de duração do aleitamento materno exclusivo até os três e seis meses de idade foram, respectivamente, de 50% e 11,9%. Em relação aos bebês que nunca foram introduzidos à mamadeira durante os três primeiros meses de vida, aqueles que usaram mamadeira tiveram menor duração média de amamentação exclusiva (15 versus 150 dias) e menor prevalência de duração de amamentação exclusiva até os três meses de idade (22,7% versus 80%). A maioria dos lactentes Terena não atingiu a duração recomendada internacionalmente para o aleitamento materno exclusivo até os seis meses, sugerindo um impacto negativo do uso da mamadeira na duração do aleitamento materno exclusivo.

Resumen En Brasil no existe información actual sobre los indicadores de lactancia materna entre los indígenas que viven en áreas urbanas. El objetivo de este estudio fue describir la duración de la lactancia materna exclusiva y sus asociaciones con las características maternas e infantiles en una cohorte de lactantes Terena. Este estudio incluyó a niños nacidos entre junio de 2017 y julio de 2018 (n = 42) y que vivían en aldeas del área urbana de Campo Grande, Mato Grosso do Sul, Brasil. La información se recopiló en cuatro momentos. Las variables sociodemográficas maternas y las características de salud materno-infantil durante la atención prenatal y el primer mes de entrevistas, respectivamente, se recogieron para este estudio. Las variables sobre prácticas de lactancia materna y alimentación con biberón fueron recolectadas de las entrevistas realizadas en el primer mes, seis meses y 12 meses. Las asociaciones pasaron por las pruebas de Wilcoxon, de Kruskal-Wallis, el chi-cuadrado de Pearson y la prueba exacta de Fisher. La prevalencia de duración de la lactancia materna exclusiva fue del 50% hasta los tres meses de edad y del 11,9% hasta los seis meses. En comparación con los bebés que no utilizaron biberón durante los primeros tres meses de vida, los que usaron biberón tuvieron una duración promedio más corta de lactancia materna exclusiva (15 versus 150 días) y una menor prevalencia de lactancia materna exclusiva hasta los tres meses de edad (22,7% versus 80%). La mayoría de los bebés Terena no alcanzaron la duración recomendada internacionalmente para la lactancia materna exclusiva hasta los seis meses, lo que sugiere un impacto negativo de la alimentación con biberón en la duración de la lactancia materna exclusiva.

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The preparation method of hydrogels has a significant effect on their structural and physicochemical properties. In this report, physically and chemically cross-linked poly(vinyl alcohol) (PVA) networks containing humic acid (HA) were alternatively prepared by autoclaving (AC) and through glutaraldehyde (GA) addition, respectively, for agricultural purposes. PVA/HA hydrogels were comparatively characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, mechanical assays, scanning electron microscopy, swelling kinetics measurements, and water retention tests in soil. AC hydrogels showed a more homogeneous porous microstructure, higher swelling levels, and a better capacity to preserve the humidity of soil than those obtained by adding GA. Both PVA/HA hydrogels exhibited no phytotoxicity on cultivation trials of Sorghum sp., but the plant growth was promoted with the GA-cross-linked network as compared to the effect of the AC sample. The release behavior of urea was modified according to the preparation method of the PVA/HA hydrogels. After 3 days of sustained urea release, 91% of the fertilizer was delivered from the AC hydrogel, whereas a lower amount of 56% was released for the GA-cross-linked hydrogel. Beyond the advantages of applying PVA/HA hydrogels in the agricultural field, an appropriate method of preparing these materials endows them with specific properties according to the requirements of the target crop.

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A nationally generalisable cohort (n 5770) was used to determine the prevalence of non-timely (early/late) introduction of complementary food and core food groups and associations with maternal sociodemographic and health behaviours in New Zealand (NZ). Variables describing maternal characteristics and infant food introduction were sourced, respectively, from interviews completed antenatally and during late infancy. The NZ Infant Feeding Guidelines were used to define early (≤ 4 months) and late (≥ 7 months) introduction. Associations were examined using multivariable multinomial regression, presented as adjusted relative risk ratios and 95 % confidence intervals (RRR; 95% CI). Complementary food introduction was early for 40·2 % and late for 3·2 %. The prevalence of early food group introduction were fruit/vegetables (23·8 %), breads/cereals (36·3 %), iron-rich foods (34·1 %) and of late were meat/meat alternatives (45·9 %), dairy products (46·2 %) and fruits/vegetables (9·9 %). Compared with infants with timely food introduction, risk of early food introduction was increased for infants: breastfed < 6months (2·52; 2·19-2·90), whose mothers were < 30 years old (1·69; 1·46-1·94), had a diploma/trade certificate v. tertiary education (1·39; 1·1-1·70), of Maori v. European ethnicity (1·40; 1·12-1·75) or smoked during pregnancy (1·88; 1·44-2·46). Risk of late food introduction decreased for infants breastfed < 6 months (0·47; 0.27-0·80) and increased for infants whose mothers had secondary v. tertiary education (2·04; 1·16-3·60) were of Asian v. European ethnicity (2·22; 1·35, 3·63) or did not attend childbirth preparation classes (2·23; 1·24-4·01). Non-timely food introduction, specifically early food introduction, is prevalent in NZ. Interventions to improve food introduction timeliness should be ethnic-specific and support longer breast-feeding.

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RESUMO Objetivo: estimar o risco de doenças cardiovasculares em indígenas Krenak por meio do Escore de Risco Cardiovascular de Framingham. Metodologia: estudo epidemiológico transversal realizado com indígenas de 30 a 74 anos, em Terra Indígena localizada na região leste de Minas Gerais, Brasil. Os dados coletados foram: peso e altura para cálculo do IMC, aferição da pressão arterial e glicemia capilar casual, sexo, idade e tabagismo. O risco cardiovascular estimado em 10 anos foi calculado a partir do algoritmo de Escore de Framingham. Além disso, foram calculados o risco cardiovascular normal, o risco cardiovascular ótimo e a idade cardiovascular. A amostra foi caracterizada com a apresentação das frequências absolutas e relativas das variáveis que compõem o escore de risco cardiovascular de Framingham, estratificada pelo sexo. Resultados: observou-se que o risco cardiovascular em 10 anos entre os indígenas Krenak foi superior ao risco normal, bem como a idade cardiovascular foi maior que a idade cronológica, apesar da maioria da amostra ter apresentado um baixo risco cardiovascular em 10 anos, sem diferença estatística entre os sexos. Conclusão: apesar da predominância de baixo risco cardiovascular em 10 anos entre os indígenas Krenak, o resultado da idade cardiovascular superior à idade cronológica pode ocasionar morbimortalidade por doenças cardiovasculares ao longo do tempo nessa população.

RESUMEN Objetivo: estimar el riesgo de las enfermedades cardiovasculares a los indígenas Krenak por medio de la Puntuación de Riesgo Cardiovascular de Framingham. Metodología: estudio epidemiológico transversal realizado con indígenas de 30 a 74 años, en Tierra Indígena localizada en la región este de Minas Gerais, Brasil. Los datos recolectados fueron: peso y altura para calcular el IMC, medición de la presión arterial y glucemia capilar casual, sexo, edad y tabaquismo. El riesgo cardiovascular estimado en 10 años fue calculado a partir del algoritmo de Puntuación de Framingham. Además, se han calculado el riesgo cardiovascular normal, el riesgo cardiovascular óptimo y la edad cardiovascular. La muestra fue caracterizada con la presentación de las frecuencias absolutas y relativas de las variables que componen la puntuación de riesgo cardiovascular de Framingham, estratificada por sexo. Resultados: se observó que el riesgo cardiovascular en 10 años entre los indígenas Krenak fue superior al riesgo normal, así como la edad cardiovascular fue mayor que la edad cronológica, aunque la mayoría de la muestra presentó un bajo riesgo cardiovascular en 10 años, sin diferencia estadística entre los sexos. Conclusión: a pesar de la predominancia de bajo riesgo cardiovascular en 10 años entre los indígenas Krenak, el resultado de la edad cardiovascular superior a la edad cronológica puede ocasionar morbimortalidad por enfermedades cardiovasculares a lo largo del tiempo en esa población.

ABSTRACT Objective: to estimate the risk of cardiovascular diseases in indigenous Krenak through the Framingham Cardiovascular Risk Score. Methodology: cross-sectional epidemiological study conducted with indigenous people aged 30 to 74 years, in Indigenous Land located in the eastern region of Minas Gerais, Brazil. The data collected were: weight and height to calculate BMI, measurement of blood pressure and casual capillary blood glucose, sex, age and smoking. The cardiovascular risk estimated at 10 years was calculated from the Framingham Score algorithm. In addition, normal cardiovascular risk, optimal cardiovascular risk and cardiovascular age were calculated. The sample was characterized with the presentation of absolute and relative frequencies of the variables that make up the cardiovascular risk score of Framingham, stratified by sex. Results: it was observed that cardiovascular risk at 10 years among the Krenak indigenous was higher than normal risk, as well as cardiovascular age was higher than chronological age, although most of the sample had a low cardiovascular risk at 10 years, no statistical difference between the sexes. Conclusion: despite the predominance of low cardiovascular risk in 10 years among the Krenak indigenous, the result of cardiovascular age above chronological age can cause morbidity and mortality from cardiovascular diseases over time in this population.

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Ommochromes are pigments of invertebrates that exhibit oxidative stress protection. The aim of this study was to investigate ommochromes extracted from cephalopod's skin for their ability to inhibit age-related-macular degeneration (AMD)-related factors such as H2O2-induced and iron-dependent oxidative stress (ferroptosis and erastin), accumulation of advanced glycation end-products (AGEs), as well as vascular endothelial growth factor (VEGF), and inflammatory cytokines (interleukin 6 and interleukin 8) secretion. As cell systems, we used primary porcine retinal pigment epithelium (RPE), human retinal pigment epithelium cell line ARPE-19 and uveal melanoma cell line OMM-1. In vitro, ommochromes produced an antiglycation effect by the inhibition of fructosylation reaction. The ommochromes showed protective effects against erastin- induced cell death in ARPE-19. In addition, in long-term stimulation (7 days) ommochromes decreased constitutively secreted VEGF, as well as interleukin 6 and interleukin 8 induced by Poly I:C in primary RPE. No relevant effects were detected in OMM-1 cells. The effects are dependent on the cell system, time of exposition, and concentration. This substance is of interest for further research concerning age-related macular degeneration.

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Cephalopods, in particular octopus (Octopus vulgaris), have the ability to alter their appearance or body pattern by showing a wide range of camouflage by virtue of their chromatophores, which contain nanostructured granules of ommochrome pigments. Recently, the antioxidant and antimicrobial activities of ommochromes have become of great interest; therefore, in this study, the pH-dependent redox effect of the extraction solvent on the antioxidant potential and the structural characterization of the pigments were evaluated. Cell viability was determined by the microdilution method in broth by turbidity, MTT, resazurin, as well as fluorescence microscopy kit assays. A Live/Dead Double Staining Kit and an ROS Kit were used to elucidate the possible inhibitory mechanisms of ommochromes against bacterial and fungal strains. The results obtained revealed that the redox state alters the color changes of the ommochromes and is dependent on the pH in the extraction solvent. Natural phenoxazinone (ommochromes) is moderately toxic to the pathogens Staphylococcus aureus, Bacillus subtilis, Salmonella Typhimurium and Candida albicans, while the species Pseudomonas aeruginosa and Pseudomonas fluorescens, and the filamentous fungi Aspergillus parasiticus, Alternaria spp. and Fusarium verticillioides, were tolerant to these pigments. UV/visible spectral scanning and Fourier- transform infrared spectroscopy (FTIR) suggest the presence of reduced ommatin in methanol/ HCl extract with high intrinsic fluorescence.

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