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Therapeutic Applications of Rosmarinic Acid in Cancer-Chemotherapy-Associated Resistance and Toxicity
No full textChemotherapeutic drugs and radiotherapy are fundamental treatments to combat cancer, but, often, the doses in these treatments are restricted by their non-selective toxicities, which affect healthy tissues surrounding tumors. On the other hand, drug resistance is recognized as the main cause of chemotherapeutic treatment failure. Rosmarinic acid (RA) is a polyphenol of the phenylpropanoid family that is widely distributed in plants and vegetables, including medicinal aromatic herbs, consumption of which has demonstrated beneficial activities as antioxidants and anti-inflammatories and reduced the risks of cancers. Recently, several studies have shown that RA is able to reverse cancer resistance to first-line chemotherapeutics, as well as play a protective role against toxicity induced by chemotherapy and radiotherapy, mainly due to its scavenger capacity. This review compiles information from 56 articles from Google Scholar, PubMed, and ClinicalTrials.gov aimed at addressing the role of RA as a complementary therapy in cancer treatment
Revised pre-Younger Dryas chronocultural sequence at the Pilauco site, north-western Patagonia (40°-44°S)
No full textThis project in southern Chile's Lake Region analysed late Pleistocene human-environment interactions. Two field seasons in 2020 and 2022 provided a new lithic collection dating to around 17 300-12 800 cal BP, which indicates human presence in north-western Patagonia prior to the Younger Dryas period
Probabilistic models for understanding inland amphipods water population abundances in Andean stream (Caspana, 23°S, Antofagasta region, Chile)
No full textThe Andes mountains in northern Chile have numerous small permanent and intermittent streams that are poorly studied; among the most reported species are amphipods of the genus Hyalella, specifically H. fossamanchini and H. kochi. The aim of the present study was to do a first characterization of populations of both amphipod species in a small stream (Caspana, 23 degrees S; 3200 m a.s.l.), that was visited in September 2022. The first results using a Kruskall-Wallis nonparametric test revealed that the abundances of both species and unidentified juveniles were not significantly different in a comparison of two sites, whereas a Mann-Wittney nonparametric U test gave similar results when each species and juveniles were compared between sites. The results of variance/mean ratio revealed the existence of an aggregated pattern, and a negative binomial distribution for all samples. The occurrence of an aggregated pattern and the consequent negative binomial distribution is a very frequent pattern for inland water invertebrates in Chilean rivers
The Genetic Dissection of Nitrogen Use-Related Traits in Flax (<i>Linum usitatissimum</i> L.) at the Seedling Stage through the Integration of Multi-Locus GWAS, RNA-seq and Genomic Selection
No full textNitrogen (N), the most important macro-nutrient for plant growth and development, is a key factor that determines crop yield. Yet its excessive applications pollute the environment and are expensive. Hence, studying nitrogen use efficiency (NUE) in crops is fundamental for sustainable agriculture. Here, an association panel consisting of 123 flax accessions was evaluated for 21 NUE-related traits at the seedling stage under optimum N (N+) and N deficiency (N-) treatments to dissect the genetic architecture of NUE-related traits using a multi-omics approach integrating genome-wide association studies (GWAS), transcriptome analysis and genomic selection (GS). Root traits exhibited significant and positive correlations with NUE under N- conditions (r = 0.33 to 0.43, p < 0.05). A total of 359 QTLs were identified, accounting for 0.11% to 23.1% of the phenotypic variation in NUE-related traits. Transcriptomic analysis identified 1034 differentially expressed genes (DEGs) under contrasting N conditions. DEGs involved in N metabolism, root development, amino acid transport and catabolism and others, were found near the QTLs. GS models to predict NUE stress tolerance index (NUE_STI) trait were tested using a random genome-wide SNP dataset and a GWAS-derived QTLs dataset. The latter produced superior prediction accuracy (r = 0.62 to 0.79) compared to the genome-wide SNP marker dataset (r = 0.11) for NUE_STI. Our results provide insights into the QTL architecture of NUE-related traits, identify candidate genes for further studies, and propose genomic breeding tools to achieve superior NUE in flax under low N input
Melatonin improves plant water status, photosynthetic performance, and antioxidant defense system in highbush blueberry<i> (Vaccinium</i><i> corymbosum</i> L.) plants subjected to drought stress
No full textDrought stress causes a decrease in agricultural yields. Recently, it has been reported that the phytohormone melatonin (MT), participates in different plant growth and developmental processes. Highbush blueberry (Vaccinium corymbosum L.) is quickly affected by drought, decreasing plant growth, yield, and quality. Thus, the aim of this study was to evaluate the role of melatonin on physiological performance, water status, chlorophyll concentration, and antioxidant metabolism in V. corymbosum plants exposed to drought stress. One-year-old V. corymbosum plants were subjected to four treatments: 1) 100% field capacity (FC) without melatonin; 2) 100% FC with 0.1 mM MT; 3) 50% FC without MT; and 4) 50% FC with MT. Plant water content, leaf area, photosynthetic performance, antioxidants compounds, and chlorophyll concentration were determined at different times post MT application (0, 3, 7, and 10 days). In our study, leaf area, plant water status, the photosynthetic performance and photosynthetic pigments decreased in the treatments with irrigation at 50% FC compared to the treatment whit irrigation at 100% FC. Interestingly, MT application improved plant water potential, CO2 assimilation, chlorophyll a, and total phenols by 35, 65, 22, and 27% respectively, at 50% FC treated with MT compared to plants without MT at 10 days of the experiment. Our results demonstrate that MT enhanced physiological and biochemical responses of V. corymbosum plants to cope with drought stress
Selenized non-<i>Saccharomyces</i> yeasts and their potential use in fish feed
No full textSelenium (Se) is a vital trace element, essential for growth and other biological functions in fish. Its significance lies in its role as a fundamental component of selenoproteins, which are crucial for optimal functioning of the organism. The inclusion of Se in the diets of farmed animals, including fish, has proved invaluable in mitigating the challenges arising from elemental deficiencies experienced in captivity conditions due to limitations in the content of fishmeal. Supplementing diets with Se enhances physiological responses, particularly mitigates the effects of the continuous presence of environmental stress factors. Organic Se has been shown to have higher absorption rates and a greater impact on bioavailability and overall health than inorganic forms. A characteristic feature of yeasts is their rapid proliferation and growth, marked by efficient mineral assimilation. Most of the selenized yeasts currently available in the market, and used predominantly in animal production and aquaculture, are based on Saccharomyces cerevisiae, which contains selenomethionine (Se-Met). The object of this review is to highlight the importance of selenized yeasts. In addition, it presents metabolic and productive aspects of other yeast genera that are important potential sources of organic selenium. Some yeast strains discussed produce metabolites of interest such as lipids, pigments, and amino acids, which could have applications in aquaculture and further enrich their usefulness
Recovering ancient parasites from Andean herbivores: test of the Mini-FLOTAC technique in archaeological samples
No full textThe optimization of techniques for recovering parasitic remains is key in paleoparasitology. The Mini-FLOTAC technique (MF) is based on passive flotation and is used for diagnosis of parasites and was never tested on ancient samples. Our objective was to assess the effectiveness of MF in paleoparasitology, aiming at improving the techniques for the recovery of parasitic remains in order to upgrade the interpretative potential of the paleoparasitological evidence. Three techniques were tested: MF, spontaneous sedimentation (SS), and centrifugation-sucrose flotation (CF) testing camelid and goat coprolites. Statistical tests were performed with the R software. Our result displayed that, in the case of SAC samples, MF recovered less number of parasitic species than SS, but obtained a greater number of positive samples for protozoa. For goat samples, MF recovered a higher number of positive samples and parasitic species than SS, added that it was the technique that recovered a greater number of parasite structures. Therefore, results vary according to the zoological origin of the samples and the parasitic species recorded. We suggest starting using MF on ancient samples as a complementary method to those traditionally used in paleoparasitology. It is important to highlight that MF was a simple and faster way. The incorporation of reliable quantitative techniques opens the door to a new way of analyzing archaeological remains, deepening the study of the parasite-host relationships and its evolution through time with an epidemiological approach. Although further studies are needed, our results suggest the complementarity of these techniques in future paleoparasitological studies
"One for all, and all for one": The problem of universals in De Ente et Essentia of Thomas Aquinas
No full textEl presente trabajo pretende estudiar la cuestión de los universales tal como Tomás de Aquino la aborda en su trabajo De ente et essentia. Busca dilucidar el modo de ser propio de los universales en tanto que accidente de la esencia absoluta presente en el entendimiento. Esto no conduce a un nominalismo ya que la esencia entendida es idéntica a la naturaleza existente en el individuo particular, desde el punto de vista de su ser absoluto. Es, en efecto, el ser absoluto de la esencia y su indiferencia con respecto a su darse, ya sea en el particular, ya sea en el entendimiento, lo que posibilita la posesión intencional del ser de lo otro que es precisamente aquello en lo que el conocer consiste en cuanto tal.The following work attempts to review the issue of the universals such as Thomas Aquinas did in his work De ente et essentia. It pretends to elucidate the specific way of being of the universals as an accident of the absolute essence present in the mind. This does not lead to nominalism because the understood essence is identical to the nature existing in the particular. This way of being of the essence is what precisely allows knowledge as an intentional possession of reality
Costanera Center como escenario de las performatividades (del poder) de la resistencia
Get PDFEl artículo profundiza en la relación entre lugar y poder, mediada por la teatralidad. Para ello, se pesquisan algunos actos corpóreos y efímeros, que consciente o inconscientemente, utilizan elementos del teatro para lograr una cierta eficacia performativa relacionada con escenificar y ejercer el poder de la resistencia en el espacio de Costanera Center, un centro comercial de Santiago, cuyos personeros han insistido en presentar como “ícono” de la ciudad y el país. Estos actos muestran cómo en dicho escenario, producto sobre todo de la desigualdad, el “espacio vivido”, en la concepción de Lefebvre, es muy distinto para muchos al “espacio concebido” y al “espacio percibido”. Como puede verse sobre todo al reparar en la dimensión del “espacio de la representación” (mediante el análisis de distintos actos), lo que para algunos es un lugar de ensueño, para otros es lo frustrante, un guión que evidencia la invisibilidad de sus vidas precarias y desechables
A feasibility study to produce biodiesel from date seed oil by using trans- esterification process
Get PDFThere is a need to produce renewable energy resources to reduce the gap between supplyand demand. The renewable energy can be generated from various kinds of resources like vegetable oils and animal fats. Biodiesel is one of alternative energy resources that can bean appealing option to solve many of global and environmental issues and crises. Production of biodiesel from several types of vegetable oils has become a promising option. The aim of this technical project is to produce biodiesel from date seed oil. The date seed oil is extracted from the date seeds. The date seed is mixed with methanol in 1:3 ratio in presence of catalyst. The mixture was kept in a hot air oven at 55 -60 degrees centigrade for six hours. The Trans esterification process produced a glycerol and methylester which is the biodiesel. The glycerol settled down due to its high-density and theupper layer was biodiesel (methyl ester) due to less density. The mixture was separatedusing a separating funnel. The biodiesel was purified by recovering methanol by usingrotary evaporator. The biodiesel produced from date seed oil is analyzed for the viscosity, density, the calorific value was also obtained, and the Flash and Fire point was performed, determine the functional elements of biodiesel using Gas Chromatography. It was observed by gas chromatography analysis that the produced biodiesel contains nearly70% of methyl ester which is a main component of biodiesel. The density of producedbiodiesel was 0.895 g/cm3.The standard biodiesel density is 0.85 g/cm3. The results were compared with standard biodiesel values. Also,the produced biodiesel has been compared with the quality of standard biodiesel.The project yielded better results.Es necesario producir recursos energéticos renovables para reducir la brecha entre la oferta y la demanda. La energía renovable se puede generar a partir de varios tipos de recursos como aceites vegetales y grasas animales. El biodiesel es uno de los recursos energéticos alternativos que puede ser una opción atractiva para resolver muchos de los problemas y crisis ambientales y globales. La producción de biodiésel a partir de varios tipos de aceites vegetales se ha convertido en una opción prometedora. El objetivo de este proyecto técnico es producir biodiesel a partir de aceite de semilla de dátil. El aceite de semilla de dátil se extrae de las semillas de dátil. La semilla de dátil se mezcla con metanol en una proporción de 1: 3 en presencia de catalizador. La mezcla se mantuvo en un horno de aire caliente a 55-60 grados centígrados durante seis horas. El proceso de transesterificación produjo un glicerol y un éster metílico que es el biodiésel. El glicerol se asienta debido a su alta densidad y la capa superior era biodiesel (éster metílico) debido a su menor densidad. La mezcla se separó usando un embudo de decantación. El biodiesel se purificó recuperando metanol usando un evaporador rotatorio. En el biodiesel producido a partir del aceite de semilla de dátil se analiza la viscosidad, densidad, también se obtuvo el poder calorífico y se realizó el Punto de Inflamación y Fuego, determinar los elementos funcionales del biodiesel mediante Cromatografía de Gases. Mediante el análisis de cromatografía de gases se observó que el biodiésel producido contiene casi un 70% de éster metílico, que es un componente principal del biodiésel. La densidad del biodiésel producido fue de 0,895 g / cm3. La densidad estándar del biodiésel es de 0,85 g / cm3. Los resultados se compararon con los valores estándar de biodiésel. Además, el biodiésel producido se ha comparado con la calidad del biodiésel estándar. El proyecto arrojó mejores resultados