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1.
Food Chem ; 460(Pt 3): 140826, 2024 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-39167868

RESUMEN

The aim of this study was to evaluate the impact of non-thermal methods, using high hydrostatic pressure (HHP) and pulsed electric field (PEF), on the dual modification of quinoa starch and to analyze the microstructural, morphological, thermal, pasting, and texture properties. Starch was treated with HHP at 400 MPa for 10 min, while PEF was applied using voltages of 10 and 30 kV cm-1 for a total time of 90s. The modification techniques were effective in breaking down amylose molecules and amylopectin branches, where for the dual treatment, higher values of DP6-12 were found. The average diameter and gelatinization temperatures were elevated after HHP, thus forming clusters that require more energy for paste formation. The use of 30 kV cm-1 and 400 MPa (HP30) in starch facilitates the creation of new food products with better texture, stability and nutritional value, making them suitable for use in food emulsions and the cosmetics industry.


Asunto(s)
Chenopodium quinoa , Presión Hidrostática , Almidón , Chenopodium quinoa/química , Almidón/química , Electricidad , Manipulación de Alimentos , Calor , Amilosa/química
2.
Int J Mol Sci ; 25(14)2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-39062747

RESUMEN

Salivary glands' neoplasms are hard to diagnose and present a complex etiology. However, several viruses have been detected in these neoplasms, such as HCMV, which can play a role in certain cancers through oncomodulation. The co-infections between HCMV with betaherpesviruses (HHV-6 and HHV-7) and polyomaviruses (JCV and BKV) has been investigated. The aim of the current study is to describe the frequency of HCMV and co-infections in patients presenting neoplastic and non-neoplastic lesions, including in the salivary gland. Multiplex quantitative polymerase chain reaction was used for betaherpesvirus and polyomavirus quantification purposes after DNA extraction. In total, 50.7% of the 67 analyzed samples were mucocele, 40.3% were adenoma pleomorphic, and 8.9% were mucoepidermoid carcinoma. Overall, 20.9% of samples presented triple-infections with HCMV/HHV-6/HHV-7, whereas 9.0% were co-infections with HCMV/HHV-6 and HCMV/HHV-7. The largest number of co-infections was detected in pleomorphic adenoma cases. All samples tested negative for polyomaviruses, such as BKV and JCV. It was possible to conclude that HCMV can be abundant in salivary gland lesions. A high viral load can be useful to help better understand the etiological role played by viruses in these lesions. A lack of JCV and BKV in the samples analyzed herein does not rule out the involvement of these viruses in one or more salivary gland lesion subtypes.


Asunto(s)
Coinfección , Infecciones por Citomegalovirus , Citomegalovirus , Neoplasias de las Glándulas Salivales , Glándulas Salivales , Humanos , Coinfección/virología , Infecciones por Citomegalovirus/virología , Infecciones por Citomegalovirus/diagnóstico , Citomegalovirus/genética , Citomegalovirus/aislamiento & purificación , Masculino , Femenino , Neoplasias de las Glándulas Salivales/virología , Persona de Mediana Edad , Adulto , Anciano , Glándulas Salivales/virología , Glándulas Salivales/patología , Adenoma/virología , Anciano de 80 o más Años , Carcinoma/virología , ADN Viral/genética , ADN Viral/análisis , Adulto Joven , Adolescente
3.
Food Chem ; 453: 139688, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-38761722

RESUMEN

The aim of this study was to evaluate the effect of freezing rates using direct (LF: Liquid nitrogen) and indirect (RF: Cryogenic refrigerator and UF: ultra-freezer) methods at temperatures of (-20, -80, and - 196 °C) on the enzymatic susceptibility with α-amylase for microparticles. In vitro digestibility parameters and technological properties were also analyzed. Lower rates resulted in larger ice crystals, damaging the starch structure. Hydrolysis was more pronounced at slower rates RF: 0.07 °C/min and UF: 0.14 °C/min, yielding maximum values of RDS: 37.63% and SDS: 59.32% for RF. Type A crystallinity remained unchanged, with only a noted increase in crystallinity of up to 6.50% for FR. Starch pastes were classified as pseudoplastic, with RF exhibiting superior textural parameters and apparent viscosity. (RF: 7.18 J g-1 and UF: 7.34 J g-1) also showed lower values of gelatinization enthalpy. Freezing techniques were viable in facilitating the diffusion of α-amylase and reducing RS by up to 81%.


Asunto(s)
Digestión , Congelación , Almidón , alfa-Amilasas , Almidón/química , Almidón/metabolismo , alfa-Amilasas/química , alfa-Amilasas/metabolismo , Hidrólisis , Viscosidad , Tamaño de la Partícula
4.
Commun Biol ; 7(1): 154, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38321111

RESUMEN

Mapping the cellular refractive index (RI) is a central task for research involving the composition of microorganisms and the development of models providing automated medical screenings with accuracy beyond 95%. These models require significantly enhancing the state-of-the-art RI mapping capabilities to provide large amounts of accurate RI data at high throughput. Here, we present a machine-learning-based technique that obtains a biological specimen's real-time RI and thickness maps from a single image acquired with a conventional color camera. This technology leverages a suitably engineered nanostructured membrane that stretches a biological analyte over its surface and absorbs transmitted light, generating complex reflection spectra from each sample point. The technique does not need pre-existing sample knowledge. It achieves 10-4 RI sensitivity and sub-nanometer thickness resolution on diffraction-limited spatial areas. We illustrate practical application by performing sub-cellular segmentation of HCT-116 colorectal cancer cells, obtaining complete three-dimensional reconstruction of the cellular regions with a characteristic length of 30 µm. These results can facilitate the development of real-time label-free technologies for biomedical studies on microscopic multicellular dynamics.


Asunto(s)
Refractometría , Humanos , Células HCT116
5.
Arq Neuropsiquiatr ; 81(6): 544-550, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37379866

RESUMEN

BACKGROUND: Sleep disorders have a negative impact on health, being associated with neurocognitive problems, cardiovascular diseases and obesity, influencing children's development and learning. OBJECTIVE: To assess the sleep pattern of people with Down syndrome (DS) and correlate changes with functionality and behavior. METHODS: A cross-sectional study was conducted to evaluate the sleep pattern in adults with DS > 18 years old. Twenty-two participants were assessed using the Pittsburgh Sleep Quality Index, the Functional Independence Measure and the Strengths and Difficulties Questionnaire, and the 11 who presented indications of disorders by the screening questionnaires were referred to polysomnography. Statistical tests were performed using a significance level of 5%, including sample normality tests and correlation tests (sleep and functionality). RESULTS: Impairment in sleep architecture was found due to an increase in the rate of awakenings in 100% of the participants, a decrease in the number of slow waves, and a high prevalence of sleep disordered breathing (SDB), with higher averages in the Apnea and Hypopnea Index (AHI) in the group. There was a negative correlation between sleep quality and global functionality (p = 0.011) and the motor (p = 0.074), cognitive (p = 0.010), and personal care (p = 0.072) dimensions in the group. Global and hyperactivity behavior changes were related to worse sleep quality (p = 0.072; p = 0.015, respectively). CONCLUSION: There is an impairment in the sleep quality of adults with DS, with an increase in the rate of awakenings, a decrease in the number of slow waves, and a high prevalence of SDB affecting this population in the functional and behavioral aspects.


ANTECEDENTES: Os distúrbios de sono têm impacto negativo na saúde, estando associados a problemas neurocognitivos, doenças cardiovasculares e obesidade, influenciando no desenvolvimento e aprendizado. OBJETIVO: Avaliar o padrão de sono de pessoas com síndrome de Down (SD) e correlacionar as alterações com a funcionalidade e comportamento. MéTODOS: Foi realizado um estudo transversal para avaliação do padrão de sono em adultos com SD > 18 anos. Foram avaliados 22 participantes, através do Índice de Qualidade do Sono de Pittsburgh, da Medida de Independência Funcional e do Questionaário de Capacidades e Dificuldades. Os 11 participantes que apresentaram indicativos de presença de distúrbios pelos questionários de triagem foram indicados a polissonografia. Os testes estatísticos foram realizados com nível de significância de 5%, incluindo testes de normalidade e testes de correlação (sono e funcionalidade). RESULTADOS: Foi encontrado prejuízo na arquitetura de sono pelo aumento do índice de despertares em 100% dos participantes, diminuição na quantidade de ondas lentas, e alta prevalência de distúrbio respiratório do sono (DRS), com maiores médias nos Índices de Apneia e Hipopneia (IAH). Houve correlação negativa entre a qualidade de sono e a funcionalidade global (p = 0,011), e as dimensões motora (p = 0,074), cognitiva (p = 0,010) e cuidados pessoais (p = 0,072). As alterações de comportamento global e comportamentos de hiperatividade foram relacionados à pior qualidade do sono (p = 0,072; p = 0,015, respectivamente). CONCLUSãO: Existe prejuízo na qualidade de sono de adultos com SD, com aumento de índice de despertares, diminuição na quantidade de ondas lentas, e alta prevalência de DRS, afetando essa população nos aspectos funcionais e comportamentais.


Asunto(s)
Síndrome de Down , Síndromes de la Apnea del Sueño , Niño , Adulto , Humanos , Adolescente , Síndrome de Down/complicaciones , Estudios Transversales , Sueño , Polisomnografía
6.
Front Microbiol ; 14: 1132781, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37152758

RESUMEN

Nanocarriers have been successfully used to solubilize, deliver, and increase the bioavailability of curcumin (CUR), but slow CUR release rates hinder its use as a topical photosensitizer in antimicrobial photodynamic therapy. A photo-responsive polymer (PRP) was designed for the light-triggered release of CUR with an effective light activation-dependent antimicrobial response. The characterization of the PRP was compared with non-responsive micelles comprising Pluronics™ P123 and F127. According to the findings, the PRP formed photo-responsive micelles in the nanometric scale (< 100 nm) with a lower critical micelle concentration (3.74 × 10-4 M-1, 5.8 × 10-4 M-1, and 7.2 × 10-6 M-1 for PRP, F127, P123, respectively, at 25°C) and higher entrapment efficiency of CUR (88.7, 77.2, and 72.3% for PRP, F127, and P123 micelles, respectively) than the pluronics evaluated. The PRP provided enhanced protection of CUR compared to P123 micelles, as demonstrated in fluorescence quenching studies. The light-triggered release of CUR from PRP occurred with UV light irradiation (at 355 nm and 25 mW cm-2) and a cumulative release of 88.34% of CUR within 1 h compared to 80% from pluronics after 36 h. In vitro studies showed that CUR-loaded PRP was non-toxic to mammal cell, showed inactivation of the pathogenic microorganisms Candida albicans, Pseudomonas aeruginosa, and methicillin-resistant Staphylococcus aureus, and decreased biofilm biomass when associated with blue light (455 nm, 33.84 J/cm2). The findings show that the CUR-loaded PRP micelle is a viable option for antimicrobial activity.

7.
Rev. Psicol., Divers. Saúde ; 12(1)fev. 2023. ilus
Artículo en Español, Portugués | LILACS | ID: biblio-1523146

RESUMEN

OBJETIVO: Identificar o conhecimento de estudantes sobre os métodos contraceptivos, antes e após a realização de oficinas sobre a temática. MÉTODOS: Pesquisa-ação, realizada com 38 estudantes do ensino médio. Foram realizadas oficinas com discussão da temática (audiogravadas) e aplicação de pré e pós-teste em outubro de 2022. Utilizou-se a análise de conteúdo temática para as narrativas e cálculo da frequência relativa para as questões fechadas do questionário. RESULTADOS: As narrativas se diferenciam entre as escolas. Os estudantes acreditam que o dispositivo intrauterino é abortivo; conhecem pouco sobre dupla proteção; e associam a pílula anticoncepcional aos benefícios à estética. Após as oficinas houve ampliação dos acertos e incorporação de novos conhecimentos mensurados pelo pós-teste nas duas escolas. CONCLUSÃO: É importante realizar oficinas no ambiente escolar a fim de reduzir danos à saúde e o Programa Saúde na Escola pode ser um facilitador para o acesso às temáticas da sexualidade e saúde reprodutiva.


OBJECTIVE: To identify students' knowledge about contraceptive methods, before and after workshops on the topic. METHODS: Action research, carried out with 38 high school students. Workshops were held with discussion of the topic (audiorecorded) and application of pre- and post-tests in October 2022. Thematic content analysis was used for the narratives and calculation of the relative frequency for the closed questions of the questionnaire. RESULTS: The narratives differ between schools. Students believe that the intrauterine device is abortifacient; they know little about double protection; and they associate the contraceptive pill with aesthetic benefits. After the workshops, there was an increase in correct answers and the incorporation of new knowledge measured by the post-test in both schools. CONCLUSION: It is important to hold workshops in the school environment in order to reduce harm to health and the School Health Program can be a facilitator for access to sexuality and reproductive health topics.


OBJETIVO: Identificar los conocimientos de los estudiantes sobre métodos anticonceptivos, antes y después de los talleres sobre el tema. MÉTODOS: Investigación acción, realizada con 38 estudiantes de secundaria. Se realizaron talleres con discusión del tema (audiograbados) y aplicación de pre y post pruebas en octubre de 2022. Para las narrativas se utilizó análisis de contenido temático y cálculo de la frecuencia relativa para las preguntas cerradas del cuestionario. RESULTADOS: Las narrativas difieren entre escuelas. Los estudiantes creen que el dispositivo intrauterino es abortivo; saben poco sobre la doble protección; y asocian la píldora anticonceptiva con beneficios estéticos. Luego de los talleres, hubo un aumento en las respuestas correctas y la incorporación de nuevos conocimientos medidos por el post-test en ambas escuelas. CONCLUSIÓN: Es importante realizar talleres en el ámbito escolar para reducir los daños a la salud y el Programa de Salud Escolar puede ser un facilitador para el acceso a temas de sexualidad y salud reproductiva.


Asunto(s)
Anticoncepción , Estudiantes , Educación Primaria y Secundaria
8.
Front Immunol ; 13: 955034, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36091027

RESUMEN

Many years ago, our research group has demonstrated extramedullary hematopoiesis in the peripheral zone of murine hepatic schistosomal granulomas. In the present study, we revisit this phenomenon using new technical and conceptual approaches. Therefore, newborn mice were percutaneously infected by Schistosoma mansoni cercariae and euthanized between 35- and 60-days post infection. Liver samples were submitted to histopathology and immunohistochemical analyses. Cells under mitosis and/or expressing Ki67 demonstrated the proliferation of hematopoietic cells both around the parasite's eggs trapped in the liver and around hepatic vessels. After 50 days post infection, proliferating cells at different levels on differentiation were located preferentially in the peripheral zone of the granulomas, around the vessels and inside the sinusoids. The presence of acidic and sulfated glycoconjugates, reticular fibers and the absence of fibronectin characterized the microenvironment for attraction and maintenance of hematopoiesis. Some neutrophils secreted MMP9 from the earliest points of infection, indicating degradation of the extracellular matrix in regions of histolysis and a possible chemoattraction of hematopoietic stem cells to the liver. Fall-3+ cells and Sca-1+ cells indicated that early hematopoietic progenitors could be mobilized to the liver. Groups of vWF+ megakaryocytes suggest chemoattraction of these cells and/or migration, proliferation, and differentiation of very immature progenitors to this organ. The increase of blood vessels and extramedullary hematopoiesis in this environment, where markers of immature hematopoietic and endothelial cells have been identified, points to the possibility of the presence of progenitors for endothelial and hematopoietic cells in the liver during the infection. There is also the possibility of concomitant migration of more differentiated hematopoietic progenitors, that proliferate and differentiate in the liver, and the occurrence of angiogenesis caused by inflammation or release of ovular antigens that stimulate the activation and proliferation of endothelial cells. Altogether, these data increase knowledge about a murine model that is of interest for investigating the pathology of the schistosomiasis and also the dynamics of hematopoiesis.


Asunto(s)
Enfermedades Hematológicas , Hematopoyesis Extramedular , Esquistosomiasis mansoni , Animales , Células Endoteliales/patología , Granuloma/patología , Enfermedades Hematológicas/patología , Hematopoyesis , Hígado/patología , Ratones , Esquistosomiasis mansoni/patología
9.
Polymers (Basel) ; 14(16)2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-36015569

RESUMEN

Natural lignocellulosic fibers (NLFs) have been extensively investigated and applied as reinforcements for polymers composites owing to improved properties associated with their cost-effectiveness and their sustainable characteristics as compared to synthetic fibers. However, an intrinsic difficulty of the hydrophilic NFL adhesion to a hydrophobic polymer matrix is still a major limitation, which might be overcome via fiber surface treatments. Among the less-known NLFs, sponge gourd (Lufta cylindrica) is a promising reinforcement for polymer composites owing to its natural network of intertwined fibers. The present work investigated for the first time the influence of a chemical treatment using silane as a coupling agent for 30 wt.% sponge gourd incorporated into a polyester matrix composite. The novel composite performance was compared with that of an untreated fiber composite via X-ray diffraction (XRD), Fourier transformed infrared spectroscopy (FTIR), Charpy impact tests, and thermogravimetric analyses (TGA). The XRD results revealed that the silanization increased the crystallinity index by 37%, which attests to the effective fiber-matrix interaction stretching of the C-H bond, as observed in its FTIR band. The silanization also increased the mean impact resistance by 10%. Although the temperatures associated with the beginning of the thermal degradation by the TGA were not affected, both the silane-treated fibers and composite displayed less thermal degradation compared with the untreated fibers. The scanning electron microscopy and energy-dispersive X-ray spectroscopy (SEM/EDS) results disclosed an improved sponge gourd fiber morphology after the silanization, which caused greater adherence to the polyester matrix. These results revealed a promising novel composite compared with other NLF polymer composites in engineering applications.

10.
Educ Inf Technol (Dordr) ; 27(2): 2807-2834, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34493924

RESUMEN

About half of the world's population remains without access to internet in an era of digital transformation. In this study, we aimed to investigate the impact of implementing the use of logic and mathematics through digital literacy on a population of elementary school students in a town in Northeast Brazil. In a non-randomized experimental longitudinal intervention study, 5th-grade students were followed during one semester. They underwent observational testing during class with the use of scales to evaluate their activities in a digital environment, and they were evaluated with respect to their ability to use digital devices. A logic/math assessment was applied prior to and at the end of the course for intervention group and compared to a control group. Questionnaires were used to assess the educators', legal guardians' and students' perceptions on digital habits and their respective sociodemographic features. The intervention consisted of a 16-h long course developed consisting of 8 2-h long classes which focused on digital technology, digital culture, and computational thinking. The students had a strong interest in the classes. Although some students did not have prior contact with computers, their development was outstanding. Digital literacy competencies and technology-use behavior increased throughout the semester independent of family income and use of digital devices at home. Students progressively improved their interaction with the computer (e.g. touchpad and typing skills) and their confidence in the digital environment. Students' scores on the logic/math assessment showed significant improvement. This was not observed in the control group, demonstrating the importance of this type of intervention even with one provided by a 16-h course. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10639-021-10711-z.

11.
Polymers (Basel) ; 13(19)2021 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-34641246

RESUMEN

Natural lignocellulose fibers have been extensively investigated and applied as a reinforcement of polymer composites in industrial applications from food packing to automotive parts. Among the advantages of natural fibers stands their relatively low cost and sustainable characteristics. These are accentuated in the case of residual fibers such as those obtained from coffee husks, an agribusiness waste, usually burnt or disposed into the environment. As composite reinforcement, hydrophilic natural fibers display adhesion problems to the most hydrophobic polymer matrices. This adhesion might be improved with distinct types of fibers surface treatments. In the present work, the effectiveness of three surface treatments applied to coffee husk fiber wastes (CHFW) were investigated, aiming to improve the tensile performance of castor oil-based polyurethane (COPU) biocomposites. The effects of treatments associated with (i) chemical with sodium hydroxide, (ii) physical by temperature and pressure and hydrothermic treatment, and (iii) biological by fermentation with Phanerochaete Chrysosporium fungus were evaluated by means of Fourier transformed infrared spectroscopy, X-ray diffraction, thermal analyses and morphology by scanning electron microscopy for different concentration of NaOH, different hydrothermic times at 121 °C/98 kPa and exposition to P. chrysosporium. The most effective treatment was the hydrothermal one at 121 °C and 98.06 kPa for 30 min. Preliminary tensile tests were performed in COPU biocomposites reinforced with 20% CHFWs subjected to the optimized conditions for each distinct type of treatment. The results indicated that the hydrothermal treatment promoted significant enhancement in the fiber/matrix interfacial bond, increasing the tensile strength up to 60% compared to COPU reinforced with in natura CHFWs fibers. It is important to mention that these composites can be applied as plastic wood for household items' internal parts and in the automobile industry.

12.
Biol Sex Differ ; 12(1): 51, 2021 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-34526108

RESUMEN

BACKGROUND: Incentives to promote drinking ("happy hour") can encourage faster rates of alcohol consumption, especially in women. Sex differences in drinking dynamics may underlie differential health vulnerabilities relating to alcohol in women versus men. Herein, we used operant procedures to model the happy hour effect and gain insight into the alcohol drinking dynamics of male and female rats. METHODS: Adult male and female Wistar rats underwent operant training to promote voluntary drinking of 10% (w/v) alcohol (8 rats/sex). We tested how drinking patterns changed after manipulating the effort required for alcohol (fixed ratio, FR), as well as the length of time in which rats had access to alcohol (self-administration session length). Rats were tested twice within the 12 h of the dark cycle, first at 2 h (early phase of the dark cycle, "early sessions") and then again at 10 h into the dark cycle (late phase of the dark cycle, "late sessions") with an 8-h break between the two sessions in the home cage. RESULTS: Adult females consumed significantly more alcohol (g/kg) than males in the 30-min sessions with the FR1 schedule of reinforcement when tested late in the dark cycle. Front-loading of alcohol was the primary factor driving higher consumption in females. Changing the schedule of reinforcement from FR1 to FR3 reduced total consumption. Notably, this manipulation had minimal effect on front-loading behavior in females, whereas front-loading behavior was significantly reduced in males when more effort was required to access alcohol. Compressing drinking access to 15 min to model a happy hour drove up front-loading behavior, generating alcohol drinking patterns in males that were similar to patterns in females (faster drinking and higher intake). CONCLUSIONS: This strategy could be useful for exploring sex differences in the neural mechanisms underlying alcohol drinking and related health vulnerabilities. Our findings also highlight the importance of the time of testing for detecting sex differences in drinking behavior.


Asunto(s)
Consumo de Bebidas Alcohólicas , Etanol , Animales , Femenino , Masculino , Ratas , Ratas Wistar , Autoadministración , Caracteres Sexuales
13.
J Occup Environ Med ; 63(6): e341-e345, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33950035

RESUMEN

OBJECTIVE: Investigating the relationship between exposure to chemical and biological agents at work and the occurrence of cardiovascular diseases in a Brazilian national health survey. METHODS: A cross-sectional study using the database of 36.442 participants from the Brazilian National Health Survey. Logistic Regression analysis was performed for multivariable models. RESULTS: After adjustments for key confounders, we observed that those individuals exposed to chemical agents and biological materials at work had 62% (95% CI: 1.20; 2.20) and 66% (95% CI: 1.03; 2.65), respectively, higher odds of having cardiovascular disease compared to employed individuals who did not report exposure to biological materials/chemical agents at work. CONCLUSION: This study draws attention to the role of chemical and biological risks in the occurrence of cardiovascular diseases. In this sense, it is necessary developing systematic and intersectoral actions for Workers' Health Surveillance to promote health and prevent chronic non-communicable diseases.


Asunto(s)
Enfermedades Cardiovasculares , Factores Biológicos , Brasil/epidemiología , Enfermedades Cardiovasculares/inducido químicamente , Enfermedades Cardiovasculares/epidemiología , Estudios Transversales , Promoción de la Salud , Humanos
14.
J Chromatogr Sci ; 59(5): 439-444, 2021 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-33558895

RESUMEN

Echinacea purpurea is a traditional medicinal plant widely used as adjuvant for the treatment of respiratory and urinary infections. Caffeic acid derivatives are considered the main active markers, such as chicoric acid, caftaric acid and chlorogenic acid. An analytical method using ultra performance liquid chromatography (UPLC) and diode array detector was developed and validated, to quantify caffeic acid derivatives in commercial dried extracts of EP. UPLC method was developed using a C18 column (50 × 2.1 mm, 1.8 µm), at 30°C. Mobile phase was composed of acetonitrile and 0.05% (v/v) formic acid aqueous solution (10:90), flow rate 0.2 mL/min. Injection volume was 10 µL and detection was performed at 300 and 330 nm. The developed method complied with all required validation parameters, and showed to be linear, precise, accurate, selective and robust for all caffeic acid derivatives. Using the validated method, the levels of caftaric acid (0.110-0.507%w/w), chicoric acid (0.040-0.179%w/w) and chlorogenic acid (0.013-0.084%w/w) were determined in five commercial dried extracts of E. purpurea, with significant variation in the contents between different samples, indicating the need of standardization and control of individual caffeic acid derivatives in commercial extracts.


Asunto(s)
Ácidos Cafeicos/análisis , Cromatografía Líquida de Alta Presión/métodos , Echinacea/química , Extractos Vegetales/química , Límite de Detección , Modelos Lineales , Reproducibilidad de los Resultados
15.
Anticancer Agents Med Chem ; 21(14): 1911-1920, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33397267

RESUMEN

BACKGROUND: Quercetin has potential against the Multidrug Resistance (MDR) phenotype, but with low bioavailability. The increase in the bioavailability can be obtained with nanostructures. OBJECTIVE: To analyze the effects of quercetin and its nanoemulsion on MDR and non-MDR cells. METHODS: We used high-pressure homogenization for nanoemulsion production; Trypan Blue for cytostatic/cytotoxicity assays; Epifluorescence microscope (with specific probes) for apoptosis and DNA damage; Real-Time PCR for gene expression; AutoDock Vina for docking and Flow Cytometry for efflux analysis. Quercetin exerted antiproliferative impact, induced apoptosis, necrosis and DNA damage on cells. RESULTS: Quercetin combined with vincristine showed an effect similar to verapamil (an ABCB1 inhibitor), and docking showed that it binds to ABCB1 in a similar region. Quercetin was also capable of altering ABCB1 gene expression. Quercetin in nanoemulsion maintained the cytotoxic and cytostatic effects of quercetin, which may increase bioavailability. Besides, the unloaded nanoemulsion was able to inhibit per se the efflux activity of ABCB1, demonstrating pharmacological action of this structure. CONCLUSION: Quercetin may be considered as a prospective drug to overcome resistance in cancer cells and its nanoemulsion can be an alternative for in vivo application.


Asunto(s)
Antineoplásicos/farmacología , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Leucemia Eritroblástica Aguda/tratamiento farmacológico , Nanopartículas/química , Quercetina/farmacología , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Daño del ADN , Ensayos de Selección de Medicamentos Antitumorales , Emulsiones , Citometría de Flujo , Humanos , Leucemia Eritroblástica Aguda/patología , Simulación del Acoplamiento Molecular , Quercetina/química , Células Tumorales Cultivadas
16.
Polymers (Basel) ; 12(12)2020 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-33260682

RESUMEN

The application of cellulose nanocrystal has lately been investigated as polymer composites reinforcement owing to favorable characteristics of biodegradability and cost effectiveness as well as superior mechanical properties. In the present work novel nanocomposites of unsaturated polyester matrix reinforced with low amount of 1, 2, and 3 wt% of cellulose nanocrystals obtained from conifer fiber (CNC) were characterized. The polyester matrix and nanocomposites were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), bending test, and thermogravimetric analysis (TGA). The result showed that the addition of only 2 wt% CNC increased the nanocomposite flexural strength by 159%, the ductility by 500% and the toughness by 1420%. Fracture analyses by SEM revealed a uniform participation of the CNC in the polyester microstructure. The resistance to thermal degradation of the CNC reinforced nanocomposites was improved in more than 20 °C as compared to neat polyester. No significant changes were detected in the water absorptions and XRD pattern of the neat polyester with incorporations up to 3 wt% CNC. These results reveal that the 2 wt% CNC nanocomposite might be a promising more ductile, lightweight and cost-effective substitute for conventional glass fiber composites in engineering applications.

17.
Geriatr Nurs ; 41(6): 899-904, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32653259

RESUMEN

Institutionalized older adults are at greater risk of malnutrition, which is associated with cognitive impairment. This study investigated the association between nutritional status, advanced activities of daily living (AADL), and cognitive function among Brazilian older adults living in care homes. This cross-sectional study was conducted on 95 older adults (73.3 ± 12.5 years). Socio-demographic variables, cognitive function (measured by Mini Mental State Examination - MMSE), AADL, Mini Nutritional Assessment (MNA), and anthropometric variables were assessed. Regarding MNA, 37.8% were malnourished, 47.3% were at risk of malnutrition, and 14.9% were well-nourished. Malnourished participants (37.8%) and those with fewer number of AADL (82.3%) showed cognitive decline (MMSE < 24) (p = 0.000 and 0.030, respectively). Inadequate waist-hip ratio was associated with cognitive decline (OR 9.3; 95% IC, 9.06 - 9.85; p = 0.03). Nutritional status and AADL were associated with cognitive function. Nutritional assessment helps to early identify malnutrition and possibly to prevent cognitive impairment.


Asunto(s)
Actividades Cotidianas , Desnutrición , Anciano , Cognición , Estudios Transversales , Evaluación Geriátrica , Humanos , Desnutrición/diagnóstico , Desnutrición/epidemiología , Evaluación Nutricional , Estado Nutricional , Prevalencia
18.
Cells Tissues Organs ; 209(1): 37-42, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32541141

RESUMEN

A biobank is an organized collection of biological human material and its associated information stored for research according to regulations under institutional responsibility, without commercial purposes, being a mandatory and strategical activity for research, regenerative medicine, and innovation. Stem cells have largely been employed in research and frequently stored in biobanks, which have been used as an essential source of biological materials. Stem cells of human exfoliated deciduous teeth (SHED) are stem cells which have a high multipotency and can be easily obtained. Besides, this extremely accessible tissue has advantages with respect to storage, as the SHED obtained in childhood can be used in later life, which implies the necessity for the creation and regulation of biobanks. The proper planning for the creation of a biobank includes knowledge of the material types to be stored, requirements regarding handling and storage conditions, storage time, and room for the number of samples. Thus, this study aimed to establish an overview of the development of a SHED biobank. Ethical and legal standardization, current applications, specific orientations, and challenges for the implementation of a SHED biobank were discussed. Through this overview, we hope to encourage further studies to use SHED biobanks.


Asunto(s)
Células Madre/metabolismo , Exfoliación Dental/metabolismo , Diente Primario/metabolismo , Brasil , Diferenciación Celular , Humanos
19.
J Cardiovasc Electrophysiol ; 31(4): 924-933, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32108399

RESUMEN

OBJECTIVE: To compare the prevalence of esophageal and periesophageal thermal injury in patients undergoing radiofrequency (RF) atrial fibrillation (AF) ablation using 8 mm tip catheters during three different esophageal protection strategies. METHODS: Forty-five consecutive patients with paroxysmal or persistent AF underwent first ablation procedure, besides esophagogastroduodenoscopy (EGD) combined with radial endosonography (EUS) performed before and after the pulmonary vein (PV) isolation. Before the procedure, patients were randomly assigned to one of three esophageal lesion protection strategies: group I-without any protective or monitoring dispositive and limiting RF applications to 30 W for 20 seconds, in left atrium posterior wall (LAPW); group II-power and time of RF delivery, up to 50 W for 20 seconds at LAPW, limited by esophageal temperature monitoring; group III-applications of RF in LAPW with fixed power application of 50 W for 20 seconds during continuous esophageal cooling. RESULTS: Baseline characteristics of patients were similar in all groups. The four PVs were isolated in 14 (93.3%), 13 (86.7%), and 15 (100%) patients, respectively in groups I, II, and III. The mean RF power was significantly higher (P < .001) in the posterior side of PVs in group III. Post-AF ablation EGD and EUS revealed two esophageal wall ulcerations and two periesophageal mediastinal edemas only in the esophageal cooling group (P = .008). CONCLUSION: Esophageal cooling balloon strategy resulted in a higher RF power energy delivery when ablating at the LA posterior wall, using 8 mm nonirrigated tip catheters under temperature mode control. Despite that, patients presented a relatively low incidence of esophageal and periesophaeal injuries.


Asunto(s)
Fibrilación Atrial/cirugía , Quemaduras/prevención & control , Ablación por Catéter , Esófago/lesiones , Venas Pulmonares/cirugía , Adulto , Brasil , Quemaduras/diagnóstico por imagen , Quemaduras/epidemiología , Catéteres Cardíacos , Ablación por Catéter/efectos adversos , Ablación por Catéter/instrumentación , Diseño de Equipo , Esófago/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Resultado del Tratamiento
20.
Pestic Biochem Physiol ; 163: 175-184, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31973855

RESUMEN

Emerging contaminants, such as the herbicides trifluralin and tebuthiuron, comprise a class of compounds for which toxicological data are lacking, especially data regarding their harmful effects and biomarkers of exposure. Their potential damage to the environment and non-target organisms makes understanding their toxic mechanisms an urgent matter. Mitochondria, which exert an energy production function, play a vital role in maintaining many cellular activities and therefore are reliable predictors of substance toxicity. This study evaluates whether the herbicides trifluralin and tebuthiuron (at concentrations ranging from 1 to 100 µM) affect isolated rat liver mitochondria. The herbicides were analyzed according to their ability to interact with the mitochondrial membrane and induce swelling, lipoperoxidation, ROS formation, and NAD(P)H oxidation; dissipate the membrane potential; dysregulate calcium homeostasis; and alter ATP and GSH/GSSG levels. Tebuthiuron does not disrupt the mitochondrial biochemistry at any of the tested concentrations. In contrast, trifluralin can disturb the mitochondrial respiration, especially at the highest concentration, but it cannot induce oxidative stress. These results suggest that the aforementioned effects can occur as toxic mechanisms of trifluralin in non-target organisms, as well.


Asunto(s)
Herbicidas , Trifluralina , Animales , Compuestos de Metilurea , Mitocondrias , Mitocondrias Hepáticas , Ratas
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