96 research outputs found

    Globalización e investigaciones biomédicas. Los ensayos clínicos en la Argentina como política cientí?ca “por default”

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    ResumenLos ensayos clínicos han sido tercerizados a los países en desarrollo —entre ellos, a la Argentina— de manera creciente desde comienzos de la década de 1990. En este artículo, se analiza este fenómeno desde la perspectiva de la teoría del sistema mundial, según la cual los países centrales dominan a los periféricos y semi-periféricos a través de relaciones de intercambio de distribución desigual. Se argumenta que se trata de un proceso global tanto desde un punto de vista metodológico como político. A nivel nacional, este proceso ha tenido un importante impacto en la investigación biomédica, a pesar de no haber sido planeado ni administrado por el gobierno nacional. En este sentido, es considerado una “política científica por default”, es decir, un proyecto iniciado y en último término dirigido por actores externos, que se bene%cian de diferentes maneras. Finalmente, se sugiere que esteproceso sólo puede ser efectivamente controlado a nivel global

    Riesgo, recursos naturales y discursos : el debate en torno a las tecnologías y el ambiente en América Latina

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    We argue here that Latin America is going through a cycle of environmental protest, as a result of two opposite forces. On the one hand, the increasing global appetite for natural resources –food, fibres, minerals, energy– has intensified the pressure on the environment in the region. After decades of neoliberal globalization, key actors in these processes are transnational corporations. On the other hand, civil society and social movements are well organized and active in responding to the social and environmental risks, in terms of both material and discursive resources. We situate our research in the confluence of three theoretical perspectives: world systems theory, contentious politics, and resistance to technologies. En este trabajo, sostenemos que América Latina está atravesando un ciclo de protesta ambiental, como resultado de dos fuerzas opuestas. Por un lado, el aumento del apetito global por los recursos naturales –alimentos, fibras, minerales, energía– ha intensificado la presión sobre el ambiente en la región. Tras décadas de globalización neoliberal, las empresas transnacionales son actores clave en estos procesos. Por otro lado, la sociedad civil y los movimientos sociales están bien organizados y son muy activos en términos de la respuesta a los riesgos sociales y ambientales derivados de los mismos, tanto en términos de los recursos materiales como de los discursivos de que disponen. Nuestro análisis se sitúa en la confluencia de tres perspectivas teóricas: la teoría de los sistemas mundiales, la política contenciosa y la resistencia a las tecnologías

    Effect of parameter calculation in direct estimation of the Lyapunov exponent in short time series

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    The literature about non-linear dynamics offers a few recommendations, which sometimes are divergent, about the criteria to be used in order to select the optimal calculus parameters in the estimation of Lyapunov exponents by direct methods. These few recommendations are circumscribed to the analysis of chaotic systems. We have found no recommendation for the estimation of λ starting from the time series of classic systems. The reason for this is the interest in distinguishing variability due to a chaotic behavior of determinist dynamic systems of variability caused by white noise or linear stochastic processes, and less in the identification of non-linear terms from the analysis of time series. In this study we have centered in the dependence of the Lyapunov exponent, obtained by means of direct estimation, of the initial distance and the time evolution. We have used generated series of chaotic systems and generated series of classic systems with varying complexity. To generate the series we have used the logistic map

    Vitamin D Deficiency Is Significantly Associated with Retinopathy in Type 2 Diabetes Mellitus: A Case-Control Study

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    Aim: Results from meta-analyses point to an association between vitamin D deficiency and the onset of diabetic retinopathy (DR). The objectives of the present study were to evaluate the association of vitamin D for the development of DR and to determine the levels of vitamin D associated with a greater risk of DR. Methods: Between November 2013 and February 2015, we performed a case-control study based on a sample of patients with diabetes in Spain. The study population comprised all patients who had at least one evaluable electroretinogram and recorded levels of 25(OH)D. We collected a series of analytical data: 25(OH)D, 1,25(OH)2D, iPTH, calcium, albumin, and HbA1c. Glycemic control was evaluated on the basis of the mean HbA1c values for the period 2009?2014. A logistic regression analysis was performed to identify the variables associated with DR. Results: The final study sample comprised 385 patients, of which 30 (7.8%) had DR. Significant differences were found between patients with and without DR for age (69.54 vs. 73.43), HbA1c (6.68% vs. 7.29%), years since diagnosis of diabetes (10.9 vs. 14.17), level of 25(OH)D (20.80 vs. 15.50 ng/mL), level of 1,25(OH)2D (35.0 vs. 24.5 pg/mL), treatment with insulin (14.9% vs. 56.7%), hypertension (77.7% vs. 100%), cardiovascular events (33.2% vs. 53.3%), and kidney failure (22.0% vs. 43.3%). In the multivariate analysis, the factors identified as independent risk factors for DR were treatment of diabetes (p = 0.001) and 25(OH)D (p = 0.025). The high risk of DR in patients receiving insulin (OR 17.01) was also noteworthy. Conclusions: Levels of 25(OH)D and treatment of diabetes were significantly associated with DR after adjusting for other risk factors. Combined levels of 25(OH)D < 16 ng/mL and levels of 1,25(OH)2D < 29 pg/mL are the variables that best predict the risk of having DR with respect to vitamin D deficiency. The risk factor with the strongest association was the treatment of type 2 diabetes mellitus. This was particularly true for patients receiving insulin, who had a greater risk of DR than those receiving insulin analogues. However, further studies are necessary before a causal relationship can be established

    Effects of ω-3 PUFA-enriched diet on growth parameters in a syngenic murine model of breast adenocarcinoma: a possible role for estrogen receptor alpha

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    Background: Breast cancer (BC) is the most common tumour among women and 75% of BC are estrogen receptor (ER)dependent. In particular, ERα promotes tumour growth, while ERβ has an anti-proliferative effect [1]. Epidemiological data have linked ω-3 polyunsaturated fatty acid (PUFA) consumption to lower incidence of BC and several experimental studies showed the anti-proliferative effects of ω-3 fish oil in different tumour models [2,3]. Chia seed oil is rich in α-linolenic acid (ALA 18:3 ω-3), while corn oil is rich in linoleic acid (LA 18:2 ω-6), precursors of eicosapentaenoic acid (EPA) and arachidonic acid (AA), respectively. Based on substrate availability, these FAs give rise to different eicosanoid signatures with opposite effects in cancer [4]. ω-3 PUFAs generate both anti-inflammatory prostanoids and reactive oxygen species (ROS), which in turn could affect NF-κB. Indeed, NF-κB belongs to a family of transcription factors with a key role in inflammation and oxidative stress, but its role in tumour development is still controversial [5]. The aim of the study was to determine possible processes that are activated by dietary lipids regulating BC growth and metastasis.Fil: Vara Messler, Marianela. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Biología Celular; Argentina.Fil: Vara Messler, Marianela. Universidad de Padova. Departamento de Ciencias Farmacéuticas y Farmacológicas; Italia.Fil: Pasqualini, María Eugenia. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Biología Celular; Argentina.Fil: Comba, Andrea. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Biología Celular. Cátedra de Biología, Histología y Embriología; Argentina.Fil:Comba, Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ciencias de la Salud; Argentina.Fil: Toniolo, Alicia. Universidad de Padova. Departamento de Ciencias Farmacéuticas y Farmacológicas; Italia.Fil: Trenti, Annalisa. Universidad de Padova. Departamento de Ciencias Farmacéuticas y Farmacológicas; Italia.Fil: Quiroga, Patricia. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Biología Celular; Argentina.Fil: Valentich, Mirta Ana. Universidad Nacional de Córdoba. Facultad de Ciencias Médicas. Instituto de Biología Celular; Argentina.Fil: Valentich, Mirta Ana. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ciencias de la Salud; Argentina.Fil: Bolego, Chiara. Universidad de Padova. Departamento de Ciencias Farmacéuticas y Farmacológicas; Italia.Otras Ciencias de la Salu

    Oxycodone/naloxone versus tapentadol in real‑world chronic non‑cancer pain management: an observational and pharmacogenetic study

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    Tapentadol (TAP) and oxycodone/naloxone (OXN) potentially offer an improved opioid tolerability. However, real-world studies in chronic non-cancer pain (CNCP) remain scarce. Our aim was to compare effectiveness and security in daily pain practice, together with the influence of pharmacogenetic markers. An observational study was developed with ambulatory test cases under TAP (n = 194) or OXN (n = 175) prescription with controls (prescribed with other opioids (control), n = 216) CNCP patients. Pain intensity and relief, quality of life, morphine equivalent daily doses (MEDD), concomitant analgesic drugs, adverse events (AEs), hospital frequentation and genetic variants of OPRM1 (rs1799971, A118G) and COMT (rs4680, G472A) genes, were analysed. Test CNCP cases evidenced a significantly higher pain relief predictable due to pain intensity and quality of life (R2 = 0.3), in front of controls. Here, OXN achieved the greatest pain relief under a 28% higher MEDD, 8-13% higher use of pregabalin and duloxetine, and 23% more prescription change due to pain, compared to TAP. Whilst, TAP yielded a better tolerability due the lower number of 4 [0-6] AEs/patient, in front of OXN. Furthermore, OXN COMT-AA homozygotes evidenced higher rates of erythema and vomiting, especially in females. CNCP real-world patients achieved higher pain relief than other traditional opioids with a better tolerability for TAP. Further research is necessary to clarify the potential influence of COMT and sex on OXN side-effects

    A Mathematical Study of Barcelona Metro Network

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    The knowledge of the topological structure and the automatic fare collection systems in urban public transport produce many data that need to be adequately analyzed, processed and presented. These data provide a powerful tool to improve the quality of transport services and plan ahead. This paper aims at studying, from a mathematical and statistical point of view, the Barcelona metro network; specifically: (1) the structural and robustness characteristics of the transportation network are computed and analyzed considering the complex network analysis; and (2) the common characteristics of the different subway stations of Barcelona, based on the passenger hourly entries, are identified through hierarchical clustering analysis. These results will be of great help in planning and restructuring transport to cope with the new social conditions, after the pandemic.This research was funded by Ministerio de Ciencia, Innovación y Universidades (MCIU, Spain), Agencia Estatal de Investigación (AEI, Spain), and Fondo Europeo de Desarrollo Regional (FEDER, UE) under project NOTREDAMME and by Scientific Research Grant of the “Fundación Memoria D. Samuel Solórzano Barruso”, University of Salamanca

    Physicochemical characteristics that influence the meat pork quality in supermarkets in the central highlands of Mexico

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    Twenty-two supermarkets in the Central Highlands of Mexico were sampled in order to classify them and to compare their pork meat quality based on its physicochemical characteristics. The supermarkets were classified in three types in accordance with socioeconomic status of buyers as low, medium, and high. Methods: Samples were obtained from the Longissimus dorsi muscle from 10th to 12th ribs. Results: Objective color was L* 46.97, a* 6.22 and b* 5.1. Subjective color indicated that it was red with a value of 3.06, subjective marbling was 2.8 %, and objective value was 2.9 %. Moisture varied from 690 to 739.3 g/kg, protein varied from 205.5 g/kg to 229. 6 g/kg and shear force (SF) was 2.87 kg/cm2 . There were no significant differences (P≥0.05) between the variables besides subjective marbling. Tukey´s test indicated that the lowest average included low and medium socioeconomic status supermarkets, which means that the fat content found in the chop eye is less than in meat in high socioeconomic level supermarkets. Conclusions and recommendations: According to the results, pork sold in the supermarkets in the Central Highlands of Mexico was a tender meat with reddish pink color, firm texture and little exudation and with an appropriate protein and intramuscular fat contents
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