432 research outputs found
Lupane-type triterpenes and their anti-cancer activities against most common malignant tumors
In recent times, a great deal of interest has been motivated on plant derived compounds known as nutraceuticals. These compounds exert important beneficial activities that improve peopleâs health status when are consumed regularly, and now they appear as a viable option to explore their possible therapeutic effects against diseases like cancer. Particularly, lupane-type triterpenes have shown great ability to modulate multiple cancer-related signaling pathways and processes, including NF-ÎșB, Wnt/ÎČ-catenin, PI3K/Akt, apoptosis, and many other routes related to proliferation or cell death, which are uncontrolled in malignant tumors. These investigations have promoted in vitro and in vivo studies, searching their mechanisms of action; although more research is still needed to prove its potential in human clinical trials. This review focuses on the ability of betulin, betulinic acid and lupeol to show benefits against the most common types of malignant tumors, which are considered a major global threat for public health
Human Rights and the Pink Tide in Latin America : Which Rights Matter?
Latin America witnessed the election of ânew Leftâ governments in the early 21 st century that, in different ways, sought to open a debate about alternatives to paradigms of neoliberal development. What has this meant for the way that human rights are understood and for patterns of human rights compliance? Using qualitative and quantitative evidence, this article discusses how human rights are imagined and the compliance records of new Left governments through the lens of the three âgenerationsâ of human rights â political and civil, social and economic, and cultural and environmental rights. The authors draw in particular on evidence from Andean countries and the Southern Cone. While basic civil and individual liberties are still far from guaranteed, especially in the Andean region, new Left countries show better overall performances in relation to socio-economic rights compared to the past and to other Latin American countries. All new Left governments also demonstrate an increasing interest in âthird generationâ (cultural and environmental) rights, though this is especially marked in the Andean Left. The authors discuss the tensions around interpretations and categories of human rights, reflect on the stagnation of first generation rights and note the difficulties associated with translating second and third generation rights into policy
Polymorphisms associated with the risk of lung cancer in a healthy Mexican Mestizo population: Application of the additive model for cancer
Lung cancer is the leading cause of cancer mortality in Mexico and worldwide. In the past decade, there has been an increase in the number of lung cancer cases in young people, which suggests an important role for genetic background in the etiology of this disease. In this study, we genetically characterized 16 polymorphisms in 12 low penetrance genes (AhR, CYP1A1, CYP2E1, EPHX1, GSTM1, GSTT1, GSTPI, XRCC1, ERCC2, MGMT, CCND1 and TP53) in 382 healthy Mexican Mestizos as the first step in elucidating the genetic structure of this population and identifying high risk individuals. All of the genotypes analyzed were in Hardy-Weinberg equilibrium, but different degrees of linkage were observed for polymorphisms in the CYP1A1 and EPHX1 genes. The genetic variability of this population was distributed in six clusters that were defined based on their genetic characteristics. The use of a polygenic model to assess the additive effect of low penetrance risk alleles identified combinations of risk genotypes that could be useful in predicting a predisposition to lung cancer. Estimation of the level of genetic susceptibility showed that the individual calculated risk value (iCRV) ranged from 1 to 16, with a higher iCRV indicating a greater genetic susceptibility to lung cancer
Th1 and Th17 hypercytokinemia as early host response signature in severe pandemic influenza
Abstract
Introduction
Human host immune response following infection with the new variant of A/H1N1 pandemic influenza virus (nvH1N1) is poorly understood. We utilize here systemic cytokine and antibody levels in evaluating differences in early immune response in both mild and severe patients infected with nvH1N1.
Methods
We profiled 29 cytokines and chemokines and evaluated the haemagglutination inhibition activity as quantitative and qualitative measurements of host immune responses in serum obtained during the first five days after symptoms onset, in two cohorts of nvH1N1 infected patients. Severe patients required hospitalization (n = 20), due to respiratory insufficiency (10 of them were admitted to the intensive care unit), while mild patients had exclusively flu-like symptoms (n = 15). A group of healthy donors was included as control (n = 15). Differences in levels of mediators between groups were assessed by using the non parametric U-Mann Whitney test. Association between variables was determined by calculating the Spearman correlation coefficient. Viral load was performed in serum by using real-time PCR targeting the neuraminidase gene.
Results
Increased levels of innate-immunity mediators (IP-10, MCP-1, MIP-1ÎČ), and the absence of anti-nvH1N1 antibodies, characterized the early response to nvH1N1 infection in both hospitalized and mild patients. High systemic levels of type-II interferon (IFN-Îł) and also of a group of mediators involved in the development of T-helper 17 (IL-8, IL-9, IL-17, IL-6) and T-helper 1 (TNF-α, IL-15, IL-12p70) responses were exclusively found in hospitalized patients. IL-15, IL-12p70, IL-6 constituted a hallmark of critical illness in our study. A significant inverse association was found between IL-6, IL-8 and PaO2 in critical patients.
Conclusions
While infection with the nvH1N1 induces a typical innate response in both mild and severe patients, severe disease with respiratory involvement is characterized by early secretion of Th17 and Th1 cytokines usually associated with cell mediated immunity but also commonly linked to the pathogenesis of autoimmune/inflammatory diseases. The exact role of Th1 and Th17 mediators in the evolution of nvH1N1 mild and severe disease merits further investigation as to the detrimental or beneficial role these cytokines play in severe illness
Ecuador's experiment in living well:Sumak kawsay, Spinoza and the inadequacy of ideas
In April 2017 Ecuador halted the continental drift to the conservative right in Latin America by electing leftist LenĂn Moreno to the Presidency. Attention has turned, therefore, to the legacy of outgoing President Rafael Correaâs decade in power. To that end, this paper examines one of Correaâs signature programmes, âBuen Vivirâ (Living Well), a strategic plan for development underscored by the indigenous Kichwa cosmology of âsumak kawsayâ. Sumak kawsay is a notion that has been co-opted into policy mechanisms in an attempt to both challenge neoliberal modes of governance, and to disrupt the ontological bifurcation of nature and society. Given the emphasis placed on ecological sensibility in sumak kawsay and Buen Vivir, critics have been quick to highlight the contradictory relations between Ecuadorâs mode of environmental governance and its extractivist agenda. Such critiques are as staid as they are well rehearsed. Acknowledging the precarious composition of sumak kawsay, the paper questions the extent to which the ethos of experimentalism in politics can be sustained, eliding stymied technocratic forms of the political. It turns, therefore, to Baruch Spinozaâs treatise on adequate and inadequate ideas. In so doing, the paper examines how one can critique an idea without perpetuating a moral economy in judgment. Consequently, the paper considers the way in which Spinozaâs thought can be charged to recuperate imperilled political ideas
Development of a Mesoamerican intra-genepool genetic map for quantitative trait loci detection in a drought tolerant Ă susceptible common bean (Phaseolus vulgaris L.) cross
Drought is a major constraint to common bean (Phaseolus vulgaris L.) production, especially in developing countries where irrigation for the crop is infrequent. The Mesoamerican genepool is the most widely grown subdivision of common beans that include small red, small cream and black seeded varieties. The objective of this study was to develop a reliable genetic map for a Mesoamerican Ă Mesoamerican drought tolerant Ă susceptible cross and to use this map to analyze the inheritance of yield traits under drought and fully irrigated conditions over 3 years of experiments. The source of drought tolerance used in the cross was the cream-seeded advanced line BAT477 crossed with the small red variety DOR364 and the population was made up of recombinant inbred lines in the F5 generation. Quantitative trait loci were detected by composite interval mapping for the traits of overall seed yield, yield per day, 100 seed weight, days to flowering and days to maturity for each field environment consisting of two treatments (irrigated and rainfed) and lattice design experiments with three repetitions for a total of six environments. The genetic map based on amplified fragment length polymorphism and random amplified polymorphic DNA markers was anchored with 60 simple sequence repeat (SSR) markers and had a total map length of 1,087.5 cM across 11 linkage groups covering the whole common bean genome with saturation of one marker every 5.9 cM. Gaps for the genetic map existed on linkage groups b03, b09 and b11 but overall there were only nine gaps larger than 15 cM. All traits were inherited quantitatively, with the greatest number for seed weight followed by yield per day, yield per se, days to flowering and days to maturity. The relevance of these results for breeding common beans is discussed in particular in the light of crop improvement for drought tolerance in the Mesoamerican genepool
Recovery of green turtle populations and their interactions with coastal dune as a baseline for an integral ecological restoration
Antecedentes y Objetivos: La restauraciĂłn ecolĂłgica se ha centrado en los componentes fĂsicos y vegetales de los ecosistemas, y ha dejado de lado a la fauna silvestre y sus interacciones. Chelonia mydas es un macroherbĂvoro en peligro de extinciĂłn que anida en playas de MĂ©xico y Cuba, e influye en la vegetaciĂłn costera con aportaciones de materia orgĂĄnica. Los objetivos de este estudio fueron analizar su recuperaciĂłn poblacional, un Ăndice del verdor de la vegetaciĂłn de duna, asĂ como la cantidad de materia orgĂĄnica estimada de sus nidadas antes y despuĂ©s de la implementaciĂłn de una Norma Oficial Mexicana.
MĂ©todos: Se analizaron datos de entre dos y tres dĂ©cadas de monitoreo biolĂłgico en 16 playas de anidaciĂłn de Chelonia mydas; a partir de ellos se realizaron tres niveles de anĂĄlisis de indicadores demogrĂĄficos, la aportaciĂłn de materia orgĂĄnica de las tortugas en la playa y el vigor vegetal a partir de sensores remotos, ademĂĄs de aplicar los estadĂsticos pertinentes.
Resultados clave: Hubo un crecimiento exponencial del nĂșmero de anidaciones de tortuga verde (entre 12 y 14% anual), asociado con pulsos de reclutamiento poblacional en los años 2000 y 2008. El aporte de materia orgĂĄnica a la playa fue significativamente mayor despuĂ©s de un cambio en la estrategia para manejo de las nidadas en MĂ©xico, y se detectĂł un incremento en el verdor de la vegetaciĂłn de duna en zonas de anidaciĂłn alta de Chelonia mydas.
Conclusiones: El incremento de las poblaciones de tortuga verde lleva a reflexionar acerca de las implicaciones que tiene la recuperaciĂłn de especies de fauna sobre otras comunidades en los ecosistemas que habitan, lo que demanda el anĂĄlisis de los paradigmas actuales y la adaptaciĂłn de estrategias que atiendan sus necesidades de manejo, procurando las condiciones de integridad ecolĂłgica de sus hĂĄbitats.Background and Aims: Ecological restoration has focused on the physical and vegetation components of ecosystems, leaving aside studies on wild fauna and their interactions. Chelonia mydas is an endangered macroherbivore that nests on sandy beaches of Mexico and Cuba, and influences the coastal vegetation with organic matter contributions. The objectives of this study were to analyze its population recovery, a greenness index for dune vegetation, and the amount of organic matter estimated from its clutches before and after the implementation of an official Mexican norm.
Methods: Biological data obtained from two and three decades of monitoring 16 Chelonia mydas nesting beaches were analyzed; based on these, three levels of demographic indexes were carried out, the contribution of organic matter by marine turtles to the beach and the vegetal vigor using remote sensing, besides implementing the pertinent statistical analysis.
Key results: There was an exponential increase of the green turtle nests (between 12 and 14% per year), associated with population recruitment pulses in 2000 and 2008. The contribution of organic matter to the beach was significantly higher after a change in clutches management in Mexico, and an increase in the dune vegetation greenness was detected in high Chelonia mydas nesting zones.
Conclusions: The increase of the green turtle populations invites to reflex about the implications of the recovery of species of fauna have on other communities in the ecosystems they inhabit, demanding the analysis of the actual paradigms and the adaptation strategies that attend their management needs, procuring the ecological integrity conditions of their habitats
Search for new physics in multijet events with at least one photon and large missing transverse momentum in proton-proton collisions at 13 TeV
A search for new physics in final states consisting of at least one photon, multiple jets, and large missing transverse momentum is presented, using proton-proton collision events at a center-of-mass energy of 13 TeV. The data correspond to an integrated luminosity of 137 fbâ1, recorded by the CMS experiment at the CERN LHC from 2016 to 2018. The events are divided into mutually exclusive bins characterized by the missing transverse momentum, the number of jets, the number of b-tagged jets, and jets consistent with the presence of hadronically decaying W, Z, or Higgs bosons. The observed data are found to be consistent with the prediction from standard model processes. The results are interpreted in the context of simplified models of pair production of supersymmetric particles via strong and electroweak interactions. Depending on the details of the signal models, gluinos and squarks of masses up to 2.35 and 1.43 TeV, respectively, and electroweakinos of masses up to 1.23 TeV are excluded at 95% confidence level
Observation of the Rare Decay of the η Meson to Four Muons
A search for the rare ηâÎŒ+ÎŒâÎŒ+ÎŒâ double-Dalitz decay is performed using a sample of proton-proton collisions, collected by the CMS experiment at the CERN LHC with high-rate muon triggers during 2017 and 2018 and corresponding to an integrated luminosity of 101ââfbâ1. A signal having a statistical significance well in excess of 5 standard deviations is observed. Using the ηâÎŒ+ÎŒâ decay as normalization, the branching fraction B(ηâÎŒ+ÎŒâÎŒ+ÎŒâ)=[5.0±0.8(stat)±0.7(syst)±0.7(B2ÎŒ)]Ă10â9 is measured, where the last term is the uncertainty in the normalization channel branching fraction. This work achieves an improved precision of over 5 orders of magnitude compared to previous results, leading to the first measurement of this branching fraction, which is found to agree with theoretical predictions
Search for a high-mass dimuon resonance produced in association with b quark jets at = 13 TeV
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