Acquisition of anoikis resistance in human osteosarcoma cells does not alter sensitivity to chemotherapeutic agents

BACKGROUND: Chemotherapy-induced cell death can involve the induction of apoptosis. Thus, aberrant function of the pathways involved might result in chemoresistance. Since cell adhesion to the extracellular matrix acts as a survival factor that homeostatically maintains normal tissue architecture, it was tested whether acquisition of resistance to deadhesion-induced apoptosis (anoikis) in human osteosarcoma would result in resistance to chemotherapy. METHODS: Osteosarcoma cell lines (SAOS-2 and TE-85) obtained from ATCC and were maintained in complete Eagle's MEM medium. Suspension culture was established by placing cells in tissue culture wells coated with poly-HEMA. Cell cytotoxicity was determined using a live/dead cytotoxicity assay. Cell cycle/apoptosis analyses were performed using propidium iodide (PI) staining with subsequent FACS analysis. Apoptosis was also assayed by Annexin-FITC/PI staining. RESULTS: Etoposide, adriamycin, vinblastine, cisplatin and paclitaxel were able to induce apoptosis in human osteosarcoma cells SAOS-2 regardless of their anoikis resistance phenotype or the culture conditions (adhered vs. suspended). Moreover, suspended anoikis resistant TE-85 cells (TE-85ar) retained their sensitivity to chemotherapy as well. CONCLUSION: Acquisition of anoikis resistance in human osteosarcoma cells does not result in a generalized resistance to all apoptotic stimuli, including chemotherapy. Moreover, our results suggest that the pathways regulating anoikis resistance and chemotherapy resistance might involve the action of different mediators

Financial Education from school age - analysis in small Municipalities in Colombia / Educação financeira desde a idade escolar - análise em pequenos Municípios da Colômbia

Financial education is an aspect that has acquired great importance in the economic development of countries, and its inclusion in basic and secondary education programs can bring benefits to the society and the economy of a country. This being the case, the financial education should not be an option but a necessary condition in the training processes, even more because we are facing generations that think in a different way, whose priorities have changed compared to those of previous generations. The measurement of the level of competences in finance has acquired such importance that different organizations such as S&P or the OECD have developed instruments for this purpose. Colombia shows a low level of development in these measurements, a fact that justifies this research with which it is sought to establish the real level of basic knowledge in finance on the part of students who are about to graduate from high scholl and enroll higher education or be integrated into the labor world, in the municipalities of Chía and Sopó, near Bogotá, capital of Colombia

Time-Restricted Feeding during Puberty Ameliorates Adiposity and Prevents Hepatic Steatosis in a Mouse Model of Childhood Obesity

: Background: Time restricted feeding (TRF) refers to dietary interventions in which food access is limited during a specific timeframe of the day. TRFs have proven useful in improving metabolic health in adult subjects with obesity. Their beneficial effects are mediated, in part, through modulating the circadian rhythm. Nevertheless, the translation of these dietary interventions onto obese/overweight children and adolescents remains uncharacterized. The objective of this study is to explore the feasibility of temporal dietary interventions for improving metabolic health in the context of childhood obesity. Methods: We have previously developed a mouse model of early adiposity (i.e., childhood obesity) through litter size reduction. Mice raised in small litters (SL) became obese as early as by two weeks of age, and as adults, they developed several obesity-related co-morbidities, including insulin resistance, glucose intolerance and hepatic steatosis. Here, we explored whether two independent short-term chrono-nutritional interventions might improve metabolic health in 1-month-old pre-pubertal SL mice. Both TRFs comprised 8 h feeding/14 h fasting. In the first one (TRF1) Control and SL mice had access to the diet for 8 h during the dark phase. In the second intervention (TRF2) food was available during the light:dark transitions. Results: TRF1 did not alter food intake nor ameliorate adiposity in SL-TRF1. In contrast, SL-TRF2 mice showed unintentional reduction of caloric intake, which was accompanied by reduced total body weight and adiposity. Strikingly, hepatic triglyceride content was completely normalized in SL-TRF1 and SL-TRF2 mice, when compared to the ad lib-fed SL mice. These effects were partially mediated by (i) clock-dependent signals, which might modulate the expression of Pparg or Cpt1a, and (ii) clockindependent signals, such as fasting itself, which could influence Fasn expression. Conclusions: Time-restricted feeding is an effective and feasible nutritional intervention to improve metabolic health, namely hepatic steatosis, in a model of childhood obesity. These data open new avenues for future safe and efficient chrono-nutritional interventions aimed to improve metabolic health in children with overweight/obesity

Treatment with Enterococcus faecalis CECT7121 Is Not Effective as Therapy in Mice with an Established Allergy Status

In allergies, an unbalanced immune response towards a T helper (Th) 2 profile with high levels of Immunoglobulin (Ig) E is produced. We have demonstrated that the pre-administration of Enterococcus faecalis CECT7121 prevents the development of allergy in ovalbumin-immunized mice. In this work, we evaluated whether this bacterium can also revert an established allergic status. Mice were immunized with ovalbumin (OVA) and after that, were inoculated with an E. faecalis CECT7121 suspension. In immunized animals, serum specific immune response, proliferative activity of memory splenocytes, and levels of Th2 cytokines were assessed. The in vivo active cutaneous anaphylaxis test was also performed. The treatment with E. faecalis CECT7121 only increased anti-OVA IgG2a levels. No differences were observed in other specific immunological parameters. Probiotic-treatment did not prove to have any desensitizing effect on mice. These results, together with those recently published, can be concluded that this bacterium would not be appropriate for the treatment of allergic symptoms.Facultad de Ciencias Médicas (FCM

Validation of the instrument Gender Sensitivity in Teaching Practice from the university student perspective

La desigualdad, inequidad y violencia de género en la educación superior son incómodos y difícil de manejar en las instituciones. En la universidad, como institución social, existen prácticas docentes que pueden reforzar, mantener, producir y reproducir los estereotipos de género o bien ayudar a modificar y colaborar con su deconstrucción. De ahí la importancia de saber cómo el estudiantado percibe estos estereotipos desde el actuar docente. Sin embargo, en la literatura revisada se observó escasez de instrumentos que permitan dar cuenta de ello. Por lo tanto, el objetivo fue el desarrollo y validación de un instrumento diseñado para medir la sensibilidad de género en las prácticas docentes a nivel superior, desde la perspectiva del estudiantado. Tal instrumento comprende cuatro dimensiones: 1) apoyo emocional, 2) manejo de conducta, 3) apoyo pedagógico y 4) lenguaje. La validación se realizó en dos fases, la primera por juezas expertas, las cuales valoraron la pertinencia y claridad de los reactivos y se calculó la razón de validez de contenido para cada uno. En la segunda, se realizó un estudio piloto con una muestra de 870 estudiantes de licenciatura para determinar las propiedades psicométricas de las dimensiones del instrumento. Se realizaron análisis factoriales exploratorios y confirmatorios y de consistencia interna a través del coeficiente alfa de Cronbach. Los resultados mostraron que las dimensiones tienen una buena estructura factorial y confiabilidad, lo cual indica que puede usarse en el ámbito universitario. La versión final del instrumento quedó conformada por 31 ítems en formato Likert y una pregunta abierta.Inequality, inequity and gender violence in higher education are uncomfortable and difficult to handle in institutions. In the university as a social institution there are teaching practices that can reinforce, maintain, produce and reproduce gender stereotypes or help modify and collaborate with their deconstruction. Hence the importance of knowing how the student perceives these stereotypes from the teaching act. However, in the reviewed literature, a shortage of instruments was observed to be considered for this. Therefore, the objective was the development and validation of an instrument designed to measure gender sensitivity in teaching practices at a higher level, from the perspective of the students. This instrument comprises four dimensions: 1) emotional support, 2) behavior management, 3) pedagogical support, and 4) language. Validation was carried out in two phases, the first by expert judges, who assessed the relevance and clarity of the items and calculated the content validity ratio for each one. In the second, a pilot study was carried out with a sample of 870 higher level students to determine the psychometric properties of the instrument’s dimensions. Exploratory and confirmatory factor analyzes and internal consistency and were carried out through Cronbach’s alpha coefficient. The results showed that the dimensions have a good factorial structure and reliability, which indicates that it can be used in the university environment. The final version of the instrument was made up of 31 items in Likert format and one open question

Italian Ryegrass Establishment by Self-Seeding in Integrated Crop-Livestock Systems: Effects of Grazing Management

Recent reports have indicated that integrated crop-livestock systems (ICLS) can enhance sustained crop and livestock production by efficiently using agricultural system resources (Liu et al. 2012). In the subtropical South American regions, soybean (Glycine max L. Merril) and maize (Zea Mays L.) crops are widely grown after Italian ryegrass (Lolium multiflorum Lam) pastures. In this system, the pasture may be established by self-seeding. Self-seedling reduces pasture production costs and extends the grazing period. The stoking method, and especially the grazing intensity, can greatly affect the quantity of seeds added to the soil by affecting the demography of the reproductive tillers. In subtropical areas where Italian ryegrass is used for winter pastures in ICLSs, the effects of crop rotation, stocking methods or grazing intensities on the subsequent ability of Italian ryegrass to self-seed are unknown. The objectives of this study are to evaluate the effects of management practices (crop rotation, stocking method and herbage allowance) on the establishment of Italian ryegrass pastures by self-seedling in an ICLS

Multiple late-Pleistocene colonisation events of the Antarctic pearlwort Colobanthus quitensis (Caryophyllaceae) reveal the recent arrival of native Antarctic vascular flora

Aim: Antarctica's remote and extreme terrestrial environments are inhabited by only two species of native vascular plants. We assessed genetic connectivity amongst Antarctic and South American populations of one of these species, Colobanthus quitensis, to determine its origin and age in Antarctica. Location: Maritime Antarctic, sub‐Antarctic islands, South America. Taxon: Antarctic pearlwort Colobanthus quitensis (Caryophyllaceae). Methods: Four chloroplast markers and one nuclear marker were sequenced from 270 samples from a latitudinal transect spanning 21–68° S. Phylogeographic, population genetic and molecular dating analyses were used to assess the demographic history of C. quitensis and the age of the species in Antarctica. Results: Maritime Antarctic populations consisted of two different haplotype clusters, occupying the northern and southern Maritime Antarctic. Molecular dating analyses suggested C. quitensis to be a young (<1 Ma) species, with contemporary population structure derived since the late‐Pleistocene. Main conclusions: The Maritime Antarctic populations likely derived from two independent, late‐Pleistocene dispersal events. Both clusters shared haplotypes with sub‐Antarctic South Georgia, suggesting higher connectivity across the Southern Ocean than previously thought. The overall findings of multiple colonization events by a vascular plant species to Antarctica, and the recent timing of these events, are of significance with respect to future colonizations of the Antarctic Peninsula by vascular plants, particularly with predicted increases in ice‐free land in this area. This study fills a significant gap in our knowledge of the age of the contemporary Antarctic terrestrial biota. Adding to previous inferences on the other Antarctic vascular plant species (the grass Deschampsia antarctica), we suggest that both angiosperm species are likely to have arrived on a recent (late‐Pleistocene) time‐scale. While most major groups of Antarctic terrestrial biota include examples of much longer‐term Antarctic persistence, the vascular flora stands out as the first identified terrestrial group that appears to be of recent origin

Neonatal overfeeding during lactation rapidly and permanently misaligns the hepatic circadian rhythm and programmes adult NAFLD

Childhood obesity is a strong risk factor for adult obesity, type 2 diabetes, and cardiovascular disease. The mechanisms that link early adiposity with late-onset chronic diseases are poorly characterised. We developed a mouse model of early adiposity through litter size reduction. Mice reared in small litters (SLs) developed obesity, insulin resistance, and hepatic steatosis during adulthood. The liver played a major role in the development of the disease. Objective: To gain insight into the molecular mechanisms that link early development and childhood obesity with adult hepatic steatosis and insulin resistance. Methods: We analysed the hepatic transcriptome (Affymetrix) of control and SL mice to uncover potential pathways involved in the long-term programming of disease in our model. Results: The circadian rhythm was the most significantly deregulated Gene Ontology term in the liver of adult SL mice. Several core clock genes, such as period 1e3 and cryptochrome 1e2, were altered in two-week-old SL mice and remained altered throughout their life course until they reached 4e6 months of age. Defective circadian rhythm was restricted to the periphery since the expression of clock genes in the hypothalamus, the central pacemaker, was normal. The period-cryptochrome genes were primarily entrained by dietary signals. Hence, restricting food availability during the light cycle only uncoupled the central rhythm from the peripheral and completely normalised hepatic triglyceride content in adult SL mice. This effect was accompanied by better re-alignment of the hepatic period genes, suggesting that they might have played a causal role in mediating hepatic steatosis in the adult SL mice. Functional downregulation of Per2 in hepatocytes in vitro confirmed that the period genes regulated lipid-related genes in part through peroxisome proliferator-activated receptor alpha (Ppara). Conclusions: The hepatic circadian rhythm matures during early development, from birth to postnatal day 30. Hence, nutritional challenges during early life may misalign the hepatic circadian rhythm and secondarily lead to metabolic derangements. Specific time-restricted feeding interventions improve metabolic health in the context of childhood obesity by partially re-aligning the peripheral circadian rhythm

Treatment with Enterococcus faecalis CECT7121 Is Not Effective as Therapy in Mice with an Established Allergy Status

In allergies, an unbalanced immune response towards a T helper (Th) 2 profile with high levels of Immunoglobulin (Ig) E is produced. We have demonstrated that the pre-administration of Enterococcus faecalis CECT7121 prevents the development of allergy in ovalbumin-immunized mice. In this work, we evaluated whether this bacterium can also revert an established allergic status. Mice were immunized with ovalbumin (OVA) and after that, were inoculated with an E. faecalis CECT7121 suspension. In immunized animals, serum specific immune response, proliferative activity of memory splenocytes, and levels of Th2 cytokines were assessed. The in vivo active cutaneous anaphylaxis test was also performed. The treatment with E. faecalis CECT7121 only increased anti-OVA IgG2a levels. No differences were observed in other specific immunological parameters. Probiotic-treatment did not prove to have any desensitizing effect on mice. These results, together with those recently published, can be concluded that this bacterium would not be appropriate for the treatment of allergic symptoms.Facultad de Ciencias Médicas (FCM

Senda Darwin Biological Station: Long-term ecological research at the interface between science and society

Indexación: Web of Science; Scielo.La Estación Biológica Senda Darwin (EBSD) constituye un centro de investigación inmerso en el paisaje rural del norte de la Isla de Chiloé (42º S), donde fragmentos del bosque siempreverde original coexisten con praderas de uso ganadero, turberas de Sphagnum, matorrales sucesionales, plantaciones de Eucalyptus y otras formaciones de origen antropogénico. Desde 1994 hemos realizado estudios de largo plazo centrados en algunas especies de plantas (e.g., Pilgerodendron uviferum D. Don) y animales (e.g., Aphrastura spinicauda Gmelin, Dromiciops gliroides [Thomas]) catalogados como amenazados o escasamente conocidos y en ecosistemas nativos de importancia regional y global (e.g., turberas de Sphagnum, bosque Valdiviano y Nordpatagónico). Las investigaciones han considerado las respuestas de las especies y de los ecosistemas frente al cambio antropogénico del paisaje y cambio climático, así como los efectos de diferentes formas de manejo. Este escenario es semejante al de otras regiones de Chile y Latinoamérica lo que da generalidad a nuestros resultados y modelos. En este período, investigadores asociados a la EBSD han producido más de un centenar de publicaciones en revistas nacionales e internacionales y 30 tesis de pre y postgrado. Entendiendo el papel clave de los seres humanos en los procesos ecológicos de la zona rural, la EBSD ha desarrollado un programa de educación ecológica y vinculación del avance científico con la sociedad local y nacional. La integración de la EBSD a la naciente red de Sitios de Estudios Socio-Ecológicos de Largo Plazo en Chile consolidará y fortalecerá la investigación básica y aplicada que realizamos para proyectarla hacia la siguiente década.Senda Darwin Biological Station (SDBS) is a field research center immersed in the rural landscape of northern Chiloé island (42º S), where remnant patches of the original evergreen forests coexist with open pastures, secondary successional shrublands, Sphagnum bogs, Eucalyptus plantations and other anthropogenic cover types, constituting an agricultural frontier similar to other regions in Chile and Latin America. Since 1994, we have conducted long-term research on selected species of plants (e.g., Pilgerodendron uviferum) and animals (e.g., Aphrastura spinicauda, Dromiciops glirioides) that are considered threatened, poorly known or important for their ecological functions in local ecosystems, and on ecosystems of regional and global relevance (e.g., Sphagnum bogs, North Patagonian and Valdivian rain forests). Research has assessed the responses of species and ecosystems to anthropogenic land-use change, climate change, and the impact of management. During this period, more than 100 scientific publications in national and international journals, and 30 theses (graduate and undergraduate) have been produced by scientists and students associated with SDBS. Because of our understanding of the key role that humans play in ecological processes at this agricultural frontier, since the establishment of SDBS we have been committed to creative research on the communication of science to society and ecological education. The integration of SDBS to the nascent Chilean network of long-term socio-ecological research will consolidate and strengthen basic and applied research to project our work into the next decade.http://ref.scielo.org/vbm4r