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1.
Food Chem ; 429: 136974, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37499504

RESUMEN

The intricate balance between the beneficial and harmful effects of selenium (Se) intake means that its quantification in food needs to be done correctly. Therefore, in this review, we systematized 105 articles to identify the most studied methodologies, analytical techniques, and food matrices. Among the analytical techniques employed, inductively coupled plasma mass spectrometry (ICP-MS) (n = 29) emerged as the most commonly used method. The most prevalent hydrolysis methodology to digest Se in food matrices involved the use of nitric acid combined with ultrasound, which improved both the yield and digestion time. Optimal recovery values were achieved when total Se quantification accounted for the sum of Se(IV) and Se(VI) (94.4-99.4%) and for SeCys (88-96.5%). These findings are relevant for advancing methodological approaches, and their results emphasize the importance of developing alternative, faster, and lower-cost protocols for Se quantification in foods and beverages.


Asunto(s)
Análisis de los Alimentos , Selenio/química , Bebidas/análisis , Límite de Detección
2.
3 Biotech ; 13(6): 186, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37193330

RESUMEN

The present study reviewed and discussed the promising affinity tags for one-step purification and immobilization of recombinant proteins. The approach used to structure this systematic review was The Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) methodology. The Scopus and Web of Science databases were used to perform the bibliographic survey by which 267 articles were selected. After the inclusion/exclusion criteria and the screening process, from 25 chosen documents, we identified 7 types of tags used in the last 10 years, carbohydrate-binding module tag (CBM), polyhistidine (His-tag), elastin-like polypeptides (ELPs), silaffin-3-derived pentalysine cluster (Sil3k tag), N-acetylmuramidase (AcmA tag), modified haloalkane dehalogenase (HaloTag®), and aldehyde from a lipase polypeptide (Aldehyde tag). The most used bacterial host for expressing the targeted protein was Escherichia coli and the most used expression vector was pET-28a. The results demonstrated two main immobilization and purification methods: the use of supports and the use of self-aggregating tags without the need of support, depending on the tag used. Besides, the chosen terminal for cloning the tag proved to be very important once it could alter enzyme activity. In conclusion, the best tag for protein one-step purification and immobilization was CBM tag, due to the eco-friendly supports that can be provided from industry wastes, the fast immobilization with high specificity, and the reduced cost of the process.

3.
Artículo en Inglés | MEDLINE | ID: mdl-36497896

RESUMEN

Certain members of the Coronaviridae family have emerged as zoonotic agents and have recently caused severe respiratory diseases in humans and animals, such as SARS, MERS, and, more recently, COVID-19. Antivirals (drugs and antiseptics) capable of controlling viruses at the site of infection are scarce. Microalgae from the Chlorellaceae family are sources of bioactive compounds with antioxidant, antiviral, and antitumor activity. In the present study, we aimed to evaluate various extracts from Planktochlorella nurekis in vitro against murine coronavirus-3 (MHV-3), which is an essential human coronavirus surrogate for laboratory assays. Methanol, hexane, and dichloromethane extracts of P. nurekis were tested in cells infected with MHV-3, and characterized by UV-vis spectrophotometry, nuclear magnetic resonance (NMR) spectroscopy, ultraperformance liquid chromatography-mass spectrometry (UPLC-MS), and the application of chemometrics through principal component analysis (PCA). All the extracts were highly efficient against MHV-3 (more than a 6 Log unit reduction), regardless of the solvent used or the concentration of the extract, but the dichloromethane extract was the most effective. Chemical characterization by spectrophotometry and NMR, with the aid of statistical analysis, showed that polyphenols, carbohydrates, and isoprene derivatives, such as terpenes and carotenoids have a more significant impact on the virucidal potential. Compounds identified by UPLC-MS were mainly lipids and only found in the dichloromethane extract. These results open new biotechnological possibilities to explore the biomass of P. nurekis; it is a natural extract and shows low cytotoxicity and an excellent antiviral effect, with low production costs, highlighting a promising potential for development and implementation of therapies against coronaviruses, such as SARS-CoV-2.


Asunto(s)
COVID-19 , Virus de la Hepatitis Murina , Animales , Ratones , Humanos , SARS-CoV-2 , Cromatografía Liquida , Espectrometría de Masas en Tándem , Antivirales/farmacología , Antivirales/uso terapéutico
4.
J Law Med Ethics ; 48(1): 142-150, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32342776

RESUMEN

At one time, specialized health privacy laws represented the bulk of the rules regulating genetic privacy, Today, however, as both the field of genomics and the content of privacy law change rapidly, a new generation of general-purpose privacy laws may impose new restrictions on collection, storage, and disclosure of genetic data. This article surveys these laws and considers implications.


Asunto(s)
Confidencialidad/legislación & jurisprudencia , Genómica , Regulación Gubernamental , Privacidad/legislación & jurisprudencia , Privacidad Genética , Humanos
5.
J Phycol ; 54(3): 380-390, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29505096

RESUMEN

Mycosporine-like amino acids (MAA) are ultraviolet screen substances synthesized by marine algae. The physiological function of these substances is related to cellular protection against UV radiation and as a protective mechanism against oxidative stress. These substances can be found mainly in the ocean, among red seaweeds. Its concentration in organisms has been related to ultraviolet radiation and availability of inorganic nitrogen in the environment. We start our study of MAA content in different species to understand if environmental conditions influence the concentration of MAAs in red seaweeds. The Brazilian coast presents abiotic factors that interact to create different physical-chemical features in the environment. We collected 441 samples from 39 species of red seaweed easily found in the intertidal zone, in low tide, during the summer of 2015. The sampling encompassed a latitudinal gradient (3° S to 28°5' S) at 23 points along the coast. We quantified and identified the content of MAAs in species through the method of high performance liquid chromatography. We detected for the first time the occurrence of MAAs in certain species of red algae that have not been reported to contain MAAs before. We confirmed that some environmental factors influenced the content of MAAs. Enhanced MAA contents, for example, were found in environments with a basic pH, a high ultraviolet index, and high concentrations of phosphate and nitrate. Salinity, dissolved oxygen and variations of sea surface temperature also influenced, in a secondary way, MAA content in algae in their natural environments.


Asunto(s)
Aminoácidos/análisis , Ambiente , Rhodophyta/química , Brasil , Algas Marinas/química
6.
J Photochem Photobiol B ; 178: 165-174, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29154200

RESUMEN

Absorption spectra are indicative of biological sample chemical composition and can be used as a basis for the construction of descriptive and predictive models for biotechnological screening or assays. In marine algae, chemical composition can vary due to species-specific differences in biochemistry, as well as intra-specific responses to unique environmental variables. Different indices (UVCi, UVB+Ai and PARi) were proposed and calculated to evaluate how photoprotective compounds vary in 18 species of Phaeophyceae. In addition, they were correlated to abiotic factors. Through this technique, seven main peaks were detected in the absorbing spectra of marine brown algal extracts. The highest photoprotective indices values were found in species collected in tropical areas, where higher solar radiation is observed compared to the southern Brazilian coast. Considering additional abiotic factors, water temperature and nitrate concentration were negatively correlated with UV indices. PARi's indices were positively affected by nitrate. All species collected on the Brazilian coast have absorption peaks in the region of phenolic compounds and carotenoids, suggesting that tropical marine brown macroalgae may have developed an effective antioxidant defense system, suggesting adaptation to environments characterized by high solar radiation. UVR/PAR indices congregated essential information to possible future biotechnological screening, facilitating selection of high priority species or sites, fostering actions to enhance alternative sustainable management strategies of coastal environments.


Asunto(s)
Absorción de Radiación , Phaeophyceae/química , Protectores contra Radiación/química , Algas Marinas/química , Rayos Ultravioleta , Brasil
7.
Nutr Hosp ; 33(1): 21-25, 2016 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-27019237

RESUMEN

Objective: To evaluate macro and micronutrients intake of adolescents living with HIV/AIDS in use of antiretroviral therapy and compare it to the Dietary Reference Intakes. Methodology: Cross-sectional study conducted with adolescents of both genders with HIV/AIDS, assessing the dietary composition of macro and micronutrients, using the 24h dietary recall. Results: 39 adolescents, average age of 15 years, 51.3% males. The participants intake of total calories, total fiber (g/d), liposoluble vitamins (A, D, E, K), vitamin B5 (mg/d), vitamin B9 (mg/d), vitamin C (mg/d), calcium (mg/d), phosphorus (mg/d), potassium (mg/d), and magnesium (mg/d) was lower than recommended. The percentages of intake lower than recommended were 79.5% for calories, 82.1% for total fibers, 89.7% for vitamin A, 100% for vitamin D, 87.2% for vitamin E, 100% for vitamin K, 71.8% for vitamin B5, 82.1% for vitamin B9, 76.9% for vitamin C, 92.3% for calcium, 61.5% for phosphorus, 97.4% for potassium, and 76.9% for magnesium. The participants ingested more carbohydrates (g), proteins (g), vitamins B2 (mg/d), B3 (mg/d), B8 (mg/d) and sodium (g/d) than recommended, the percentages above the recommendations being 92.3% for carbohydrates, 64.1% for proteins and vitamin B2, 56.4% for vitamin B3, 82.1% for vitamin B8, and 59% for sodium. The remaining nutrients were within the amounts recommended by the DRIs. Conclusion: Food intake was inadequate as compared to the recommendations of the International Nutrition Guidelines.


Objetivo: identificar la ingestión alimentaria de macro y micronutrientes en adolescentes viviendo con VIH/sida que usan terapia anti-retroviral y compararlos a las Dietary Reference Intakes. Metodología: estudio transversal realizado con adolescentes de ambos sexos con VIH/sida, en el que se evaluó la composición dietética de macro y micronutrientes a través del recordatorio alimentario de 24h. Resultados: 39 adolescentes con una edad promedio de 15 años, un 51,3% del sexo masculino. Los participantes consumieron menos calorías totales en la dieta, fibra total (g/d), vitaminas liposolubles (A, D, E, K), vitamina B5 (mg/d), vitamina B9 (mg/d), vitamina C (mg/d), calcio (mg/d), fósforo (mg/d), potasio (mg/d) y magnesio (mg/d) que lo recomendado. Los porcentajes de ingestión por debajo de lo recomendado representaron el 79,5% para las calorías, el 82,1% para la fibra total, el 89,7% para la vitamina A, el 100% para la vitamina D, el 87,2% para la vitamina E, el 100% para la vitamina K, el 71,8% para la vitamina B5, el 82,1% para la vitamina B9, el 76,9% para la vitamina C, el 92,3% para el calcio, el 61,5% para el fósforo, el 97,4% para el potasio y el 76,9% para el magnesio. Los participantes consumían más carbohidratos (g), proteínas (g), vitaminas B2 (mg/d), B3 (mg/d), B8 (mg/d) y sodio (g/d) de lo recomendado, representando porcentajes por encima de la ingestión del 92,3% para los hidratos de carbono, del 64,1% para las proteínas y la vitamina B2, del 56,4% para la vitamina B3, del 82,1% para la vitamina B8 y del 59% para el sodio. Los demás nutrientes estaban dentro de lo recomendado por las DRIs. Conclusión: el consumo alimentario fue inadecuado en comparación con lo recomendado por las Directrices Internacionales de Nutrición.


Asunto(s)
Terapia Antirretroviral Altamente Activa , Infecciones por VIH/complicaciones , Infecciones por VIH/metabolismo , Desnutrición/complicaciones , Trastornos Nutricionales/complicaciones , Adolescente , Estudios Transversales , Ingestión de Alimentos , Ingestión de Energía , Femenino , Humanos , Masculino , Vitaminas
8.
Nutr. hosp ; 33(1): 21-25, ene.-feb. 2016. tab
Artículo en Inglés | IBECS | ID: ibc-153030

RESUMEN

Objective: To evaluate macro and micronutrients intake of adolescents living with HIV/AIDS in use of antiretroviral therapy and compare it to the Dietary Reference Intakes. Methodology: Cross-sectional study conducted with adolescents of both genders with HIV/AIDS, assessing the dietary composition of macro and micronutrients, using the 24h dietary recall. Results: 39 adolescents, average age of 15 years, 51.3% males. The participants intake of total calories, total fiber (g/d), liposoluble vitamins (A, D, E, K), vitamin B5 (mg/d), vitamin B9 (mg/d), vitamin C (mg/d), calcium (mg/d), phosphorus (mg/d), potassium (mg/d), and magnesium (mg/d) was lower than recommended. The percentages of intake lower than recommended were 79.5% for calories, 82.1% for total fibers, 89.7% for vitamin A, 100% for vitamin D, 87.2% for vitamin E, 100% for vitamin K, 71.8% for vitamin B5, 82.1% for vitamin B9, 76.9% for vitamin C, 92.3% for calcium, 61.5% for phosphorus, 97.4% for potassium, and 76.9% for magnesium. The participants ingested more carbohydrates (g), proteins (g), vitamins B2 (mg/d), B3 (mg/d), B8 (mg/d) and sodium (g/d) than recommended, the percentages above the recommendations being 92.3% for carbohydrates, 64.1% for proteins and vitamin B2, 56.4% for vitamin B3, 82.1% for vitamin B8, and 59% for sodium. The remaining nutrients were within the amounts recommended by the DRIs. Conclusion: Food intake was inadequate as compared to the recommendations of the International Nutrition Guidelines (AU)


Objetivo: identificar la ingestión alimentaria de macro y micronutrientes en adolescentes viviendo con VIH/sida que usan terapia anti-retroviral y compararlos a las Dietary Reference Intakes. Metodología: estudio transversal realizado con adolescentes de ambos sexos con VIH/sida, en el que se evaluó la composición dietética de macro y micronutrientes a través del recordatorio alimentario de 24h. Resultados: 39 adolescentes con una edad promedio de 15 años, un 51,3% del sexo masculino. Los participantes consumieron menos calorías totales en la dieta, fibra total (g/d), vitaminas liposolubles (A, D, E, K), vitamina B5 (mg/d), vitamina B9 (mg/d), vitamina C (mg/d), calcio (mg/d), fósforo (mg/d), potasio (mg/d) y magnesio (mg/d) que lo recomendado. Los porcentajes de ingestión por debajo de lo recomendado representaron el 79,5% para las calorías, el 82,1% para la fibra total, el 89,7% para la vitamina A, el 100% para la vitamina D, el 87,2% para la vitamina E, el 100% para la vitamina K, el 71,8% para la vitamina B5, el 82,1% para la vitamina B9, el 76,9% para la vitamina C, el 92,3% para el calcio, el 61,5% para el fósforo, el 97,4% para el potasio y el 76,9% para el magnesio. Los participantes consumían más carbohidratos (g), proteínas (g), vitaminas B2 (mg/d), B3 (mg/d), B8 (mg/d) y sodio (g/d) de lo recomendado, representando porcentajes por encima de la ingestión del 92,3% para los hidratos de carbono, del 64,1% para las proteínas y la vitamina B2, del 56,4% para la vitamina B3, del 82,1% para la vitamina B8 y del 59% para el sodio. Los demás nutrientes estaban dentro de lo recomendado por las DRIs. Conclusión: el consumo alimentario fue inadecuado en comparación con lo recomendado por las Directrices Internacionales de Nutrición (AU)


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Nutrientes , Micronutrientes/análisis , Infecciones por VIH/tratamiento farmacológico , Antirretrovirales/uso terapéutico , Evaluación Nutricional , Estado Nutricional , Desnutrición/epidemiología
9.
Dev Biol ; 316(2): 249-59, 2008 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-18328472

RESUMEN

Cadherins are one of the major families of adhesion molecules with diverse functions during embryonic development. Fat-like cadherins form an evolutionarily conserved subgroup characterized by an unusually large number of cadherin repeats in the extracellular domain. Here we describe the role of the Fat-like cadherin CDH-4 in Caenorhabditis elegans development. Cdh-4 mutants are characterized by hypodermal defects leading to incompletely penetrant embryonic or larval lethality with variable morphogenetic defects. Independently of the morphogenetic defects cdh-4 mutant animals also exhibit fasciculation defects in the ventral and dorsal cord, the major longitudinal axon tracts, as well as migration defects of the Q neuroblasts. In addition CDH-4 is essential for establishing and maintaining the attachment between the buccal cavity and the pharynx. Cdh-4 is expressed widely in most affected cells and tissues during embryogenesis suggesting that CDH-4 functions to ensure that proper cell contacts are made and maintained during development.


Asunto(s)
Axones/fisiología , Cadherinas/fisiología , Proteínas de Caenorhabditis elegans/fisiología , Caenorhabditis elegans/embriología , Movimiento Celular/fisiología , Faringe/embriología , Tejido Subcutáneo/embriología , Animales , Fasciculación , Tejido Subcutáneo/fisiología
10.
Proc Natl Acad Sci U S A ; 104(3): 834-9, 2007 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-17213328

RESUMEN

The navigation of axons toward their targets is a highly dynamic and precisely regulated process during nervous system development. The molecular basis of this navigation process is only partly understood. In Caenorhabditis elegans, we isolated the RNAi-hypersensitive strain nre-1(hd20) lin-15b(hd126), which allows us to phenocopy axon guidance defects of known genes by feeding RNAi. We used this mutant strain to systematically screen 4,577 genes on chromosomes I and III for axon guidance phenotypes. We identified 93 genes whose down-regulation led to penetrant ventral cord fasciculation defects or motoneuron commissure outgrowth defects. These genes encode various classes of proteins, ranging from secreted or putative cell surface proteins to transcription factors controlling gene expression. A majority of the genes is evolutionary conserved and previously uncharacterized. In addition, we found axon guidance functions for known genes like pry-1, a component of the Wnt-signaling pathway, and ced-1, a receptor required for the engulfment of neurons undergoing apoptosis during development. Our screen provides insights into molecular pathways operating during the generation of neuronal circuits and provides a basis for a more detailed analysis of gene networks regulating axon navigation.


Asunto(s)
Axones/metabolismo , Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/genética , Interferencia de ARN , Animales , Caenorhabditis elegans/clasificación , Caenorhabditis elegans/crecimiento & desarrollo , Regulación del Desarrollo de la Expresión Génica , Proteínas de la Membrana/genética , Mutación/genética , Fenotipo
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