Efecto de la quercetina sobre la tasa de desarrollo y la viabilidad de embriones bovinos producidos in vitro

The development rates and the quality of the bovine embryos produced in vitro are lower than those produced in vivo, due to the oxidative stress to which they are subjected during their manipulation and the culture conditions. The aim of this study was to evaluate the production, cellularity and vitality of bovine blastocysts produced in vitro with different concentrations of quercetin. A total of 2108 oocytes were matured in vitro in medium 199 with 10% FBS, 5.0 μg/ml LH and 0.5 μg/ml FSH. Fertilization was carried out in TALP medium with 2x106 spermatozoa/ml. Potential zygotes were cultured at 38.7 °C with 5% CO2 in SOF culture medium supplemented with six concentrations of quercetin (1, 5, 10, 15, 20, 50 μM) and as controls were used the SOF medium without quercetin and supplemented with DMSO. The rates of cleavage (day 2) and blastocysts (day 7) were determined, as well as the cellularity and cell viability of the blastocysts. An analysis of variance was performed, and the means of the treatments were compared with the Tukey test. Treatments with 1 and 5 μM of quercetin were higher for the blastocyst rate (p<0.05). A reduction in the cleavage rate, the blastocyst rate and cell viability were observed for 20 and 50 μM, and a decrease in cellularity for 15 μM was found. Quercetin used at low concentrations during the in vitro culture of bovine embryos produces an increase in the rate of blastocysts, while the use of high concentrations of quercetin generates deleterious effects in bovine embryos.Las tasas de desarrollo y la calidad de los embriones bovinos producidos in vitro son menores que los producidos in vivo, debido al estrés oxidativo al que son sometidos durante su manipulación y las condiciones de cultivo. El objetivo de este estudio fue evaluar la producción, la celularidad y la vitalidad de los blastocistos bovinos producidos in vitro con diferentes concentraciones de quercetina. Un total de 2108 oocitos fueron madurados in vitro en medio 199 con 10% de SFB, 5.0 μg/ml de LH y 0.5 μg/ml de FSH. La fertilización se realizó en medio TALP con 2x106 espermatozoides/ml. Los posibles cigotos fueron cultivados a 38.7 °C con 5% de CO2 en medio de cultivo SOF suplementado con seis concentraciones de quercetina (1, 5, 10, 15, 20, 50 µM) y como controles se utilizaron el medio SOF sin quercetina y suplementado con DMSO. Se determinaron las tasas de clivaje (día 2) y blastocistos (día 7), así como la celularidad y la viabilidad celular de los blastocistos. Se realizó un análisis de varianza y las medias de los tratamientos se compararon con la prueba de Tukey. Los tratamientos con 1 y 5 µM de quercetina fueron superiores para la tasa de blastocistos (p<0.05). Se observó una reducción en la tasa de clivaje, la tasa de blastocistos y la viabilidad celular para 20 y 50 µM, y se encontró una disminución en la celularidad para 15 µM. La quercetina utilizada a bajas concentraciones durante el cultivo in vitro de embriones bovinos produce un incremento en la tasa de blastocistos, mientras que el uso altas concentraciones de quercetina genera efectos deletéreos en los embriones bovinos

Hydrological regime of remote catchments with extreme gradients under accelerated change: the Baker basin in Patagonia

The Baker basin (27 000 km2) is located in one of the most pristine and remote areas of the planet. Its hydrological regime is poised to undergo dramatic changes in the near future due to hydropower development and climate change. The basin contains the second-largest lake in South America, and part of a major icefield. This study documents the natural baseline of the Baker River basin, discusses the main hydrological modes and analyses the potential for sustainable management. Annual precipitation varies several-fold from the eastern Patagonian steppes to the North Patagonian Icefield. The westernmost sub-basins are strongly governed by glacier melt with a peak discharge in the austral summer (January–March). The easternmost sub-basins have a much more seasonal response governed by quicker snowmelt in spring (November–December), while they exhibit low flows typical for semi-arid regions during summer and autumn. Topography, vegetation and wetlands may also influence streamflow. The strong spatio-temporal gradients and variability highlight the need for further monitoring, particularly in the headwaters, especially given the severe changes these basins are expected to undergo. The great diversity of hydrological controls and climate change pose significant challenges for hydrological prediction and management

Relational Quantum Mechanics

I suggest that the common unease with taking quantum mechanics as a fundamental description of nature (the "measurement problem") could derive from the use of an incorrect notion, as the unease with the Lorentz transformations before Einstein derived from the notion of observer-independent time. I suggest that this incorrect notion is the notion of observer-independent state of a system (or observer-independent values of physical quantities). I reformulate the problem of the "interpretation of quantum mechanics" as the problem of deriving the formalism from a few simple physical postulates. I consider a reformulation of quantum mechanics in terms of information theory. All systems are assumed to be equivalent, there is no observer-observed distinction, and the theory describes only the information that systems have about each other; nevertheless, the theory is complete.Comment: Substantially revised version. LaTeX fil

A compilation of field surveys on gaseous elemental mercury (GEM) from contrasting environmental settings in Europe, South America, South Africa and China: separating fads from facts

Mercury is transported globally in the atmosphere mostly in gaseous elemental form (GEM, Hg0 gas), but still few worldwide studies taking into account different and contrasted environmental settings are available in a single publication. This work presents and discusses data from Argentina, Bolivia, Bosnia and Herzegovina, Brazil, Chile, China, Croatia, Finland, Italy, Russia, South Africa, Spain, Slovenia and Venezuela. We classified the information in four groups: (1) mining districts where this contaminant poses or has posed a risk for human populations and/or ecosystems; (2) cities, where the concentration ofatmospheric mercury could be higher than normal due to the burning of fossil fuels and industrial activities; (3) areas with natural emissions from volcanoes; and (4) pristine areas where no anthropogenic influence was apparent. All the surveys were performed using portable LUMEX RA-915 series atomic absorption spectrometers. The results for cities fall within a low GEM concentration range that rarely exceeds 30 ng m-3, that is, 6.6 times lower than the restrictive ATSDR threshold (200 ng m-3) for chronic exposure to this pollutant. We also observed this behavior in the former mercury mining districts, where few data were above 200 ng m-3.We noted that high concentrations of GEM are localized phenomena that fade away in short distances. However, this does not imply that they do not pose a risk for those working in close proximity to the source. This is the case of the artisanal gold miners that heat the Au–Hg amalgam to vaporize mercury. In this respect, while GEM can be truly regarded as a hazard, because of possible physical–chemical transformations into other species, it is only under these localized conditions, implying exposure to high GEM concentrations, which it becomes a direct risk for humans.Grants CGL2009-13171 and CTM2012-33918 from the Spanish Ministry of Economy and Competitiveness and PII1I09-0142- 4389 from theCastilla-LaMancha (Spain)RegionalGovernment.Published713-7346A. Monitoraggio ambientale, sicurezza e territorioJCR Journalrestricte

WHO systematic review of prevalence of chronic pelvic pain: a neglected reproductive health morbidity

BACKGROUND: Health care planning for chronic pelvic pain (CPP), an important cause of morbidity amongst women is hampered due to lack of clear collated summaries of its basic epidemiological data. We systematically reviewed worldwide literature on the prevalence of different types of CPP to assess the geographical distribution of data, and to explore sources of variation in its estimates. METHODS: We identified data available from Medline (1966 to 2004), Embase (1980 to 2004), PsycINFO (1887 to 2003), LILACS (1982 to 2004), Science Citation index, CINAHL (January 1980 to 2004) and hand searching of reference lists. Two reviewers extracted data independently, using a piloted form, on participants' characteristics, study quality and rates of CPP. We considered a study to be of high quality (valid) if had at least three of the following features: prospective design, validated measurement tool, adequate sampling method, sample size estimation and response rate >80%. We performed both univariate and multivariate meta-regression analysis to explore heterogeneity of results across studies. RESULTS: There were 178 studies (459975 participants) in 148 articles. Of these, 106 studies were (124259 participants) on dysmenorrhoea, 54 (35973 participants) on dyspareunia and 18 (301756 participants) on noncyclical pain. There were only 19/95 (20%) less developed and 1/45 (2.2%) least developed countries with relevant data in contrast to 22/43 (51.2%) developed countries. Meta-regression analysis showed that rates of pain varied according to study quality features. There were 40 (22.5%) high quality studies with representative samples. Amongst them, the rate of dysmenorrhoea was 16.8 to 81%, that of dyspareunia was 8 to 21.8%, and that for noncyclical pain was 2.1 to 24%. CONCLUSION: There were few valid population based estimates of disease burden due to CPP from less developed countries. The variation in rates of CPP worldwide was due to variable study quality. Where valid data were available, a high disease burden of all types of pelvic pain was found

Computing, Design, Art: Reflections on an Innovative Moment in History

The paper is concerned with the role of art and design in the history and philosophy of computing. It offers insights arising from research into a period in the 1960s and 70s, particularly in the UK, when computing became more available to artists and designers, focusing on John Lansdown (1929-1999) and Bruce Archer (1922-2005) in London. Models of computing interacted with conceptualisations of art, design and related creative activities in important ways

Distribution of GABAergic Interneurons and Dopaminergic Cells in the Functional Territories of the Human Striatum

BACKGROUND: The afferent projections of the striatum (caudate nucleus and putamen) are segregated in three territories: associative, sensorimotor and limbic. Striatal interneurons are in part responsible for the integration of these different types of information. Among them, GABAergic interneurons are the most abundant, and can be sorted in three populations according to their content in the calcium binding proteins calretinin (CR), parvalbumin (PV) and calbindin (CB). Conversely, striatal dopaminergic cells (whose role as interneurons is still unclear) are scarce. This study aims to analyze the interneuron distribution in the striatal functional territories, as well as their organization regarding to the striosomal compartment. METHODOLOGY/PRINCIPAL FINDINGS: We used immunohistochemical methods to visualize CR, PV, CB and tyrosine hydroxylase (TH) positive striatal neurons. The interneuronal distribution was assessed by stereological methods applied to every striatal functional territory. Considering the four cell groups altogether, their density was higher in the associative (2120±91 cells/mm(3)) than in the sensorimotor (959±47 cells/mm(3)) or limbic (633±119 cells/mm(3)) territories. CB- and TH-immunoreactive(-ir) cells were distributed rather homogeneously in the three striatal territories. However, the density of CR and PV interneurons were more abundant in the associative and sensorimotor striatum, respectively. Regarding to their compartmental organization, CR-ir interneurons were frequently found in the border between compartments in the associative and sensorimotor territories, and CB-ir interneurons abounded at the striosome/matrix border in the sensorimotor domain. CONCLUSIONS/SIGNIFICANCE: The present study demonstrates that the architecture of the human striatum in terms of its interneuron composition varies in its three functional territories. Furthermore, our data highlight the importance of CR-ir striatal interneurons in the integration of associative information, and the selective role of PV-ir interneurons in the motor territory. On the other hand, the low density of dopaminergic cells casts doubts about their role in the normal human striatum