695 research outputs found

    Use of multivariate analysis in the non-genetic factors assessment of Creole goats

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    El peso al nacimiento en caprinos es un factor que siempre se pondera en los esquemas productivos por estar positivamente correlacionado con la tasa de crecimiento, con el tamaño del adulto, con el tiempo que tardan las crías en alcanzar peso de faena y con el tipo de alimentación que reciben. El peso al nacimiento varía en las distintas razas por ser determinado genéticamente. Hay productores que llegan a cambiar la raza de cabra buscando mejores pesos al nacimiento y desarrollos más precoces. Existen, sin embargo, factores no genéticos, que influyen en el peso al nacimiento y el desarrollo inicial que pueden llevar a confundir los resultados cuando se comparan diferentes razas buscando la producción de cabritos de mejores pesos al nacimiento y desarrollos más precoces. Sexo y número de camada son dos factores no genéticos relevantes en la determinación del peso al nacimiento y ya han sido demostrados en otras razas. En cabras Criollas, además de estos, se detecta que edad de la madre, número de parto de la madre, y mes de nacimiento también influyen. Se realizó un estudio de la influencia de todas estas variables en el peso al nacimiento y desarrollo inicial en un rebaño caprino de la Universidad Nacional de Santiago del Estero (UNSE), en el que se pesaron crías al nacimiento y en desarrollo inicial en cinco pariciones sucesivas. Se aplicó un análisis conjunto de todas las variables o multivariado, empleándose el método de componentes principales ACP, el cual detectó relaciones muy estrechas entre las variables en los tres ejes principales: 1) edad de la madre con número de parto, 2) peso con el tamaño de la camada y 3) otras relaciones, aunque débiles entre sexo y tamaño de camada. El ACP sirvió para sintetizar la información y mejorar la eficiencia en la interpretación de resultados, concentrando a los ejemplares en base a la influencia de las variables estudiadas con sus respectivos pesos al nacimiento, siendo los grupos 2 y 3 los de mayores pesos (3,18 kg y 3.4 kg respectivamente) y los bajos pesos para los grupos 1 y 4 (2,22 kg y 2,25 kg promedio, respectivamente).In goats, birth weight is a factor that is always taken into account in the production systems since it correlates positively with growth rate, with adult size, with the time required for the offspring reach slaughter weight and with the type of food they receive. Birth weight varies in different races to be genetically determined. There are breeders who change the race of goat focusing on the better birth weight and more early development. However, there are non-genetic factors that influence on the birth weight and early development that can lead to confusing results when comparing different races to looking offspring production of better birth weight and early development. Sex and number of litter are two non genetic factors relevant in determining birth weight, that in addition already it was demonstrated in other races. In Creole goats in addition to these, we found that age of mother, calving number of the mother, and birth month also have influence. A study of the influence of these variables on birth weight and initial development in a goat herd was conducted at the Na-tional University of Santiago del Estero. In this study the offspring were weighed at birth and during early developmental conducted in five successive calving. A pooled analysis of all variables or multivariate analyzes were applied, using the method of principal component ACP, which detect very close relations between the variables in the three major axis: 1) age of mother with calving number, 2) weight with the litter size and 3) other relationships, though weak between sex and litter size. This method, ACP, helped to summarize information and improving efficiency in the interpretation of results, bringing together animals based on the influence of the variables studied and their birth weight. Thus the groups 2 and 3 they presented the higher weights (3.18 kg and 3.4 kg respectively), and groups 1 and 4, lower weights (2.22 kg and 2.25 kg average respectively).Fil: David, R. N.. Universidad Nacional de Santiago del Estero. Facultad de Agronomía y Agroindustrias; ArgentinaFil: Abdala, G. C.. Universidad Nacional de Santiago del Estero. Facultad de Agronomía y Agroindustrias; ArgentinaFil: Abdala, María Eugenia. Universidad Nacional de Santiago del Estero. Facultad de Agronomía y Agroindustrias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Lescano, J. A.. Universidad Nacional de Santiago del Estero. Facultad de Agronomía y Agroindustrias; Argentin

    First record of non-mammalian cynodonts (Therapsida) in the Sanga do Cabral Formation (Early Triassic) of southern Brazil

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    New material from the Sanga do Cabral Formation in southern Brazil is described, including one distal and three proximal portions of femora, and a distal portion of a humerus. Comparative studies indicate affinities of the proximal femora and the distal humerus with non-mammalian cynodonts, whereas the distal femur cannot be attributed with certainty to this group. These postcranial elements are the first record of non-mammalian cynodonts for the Sang a do Cabral Formation and demonstrate the presence of small- to medium-sized representatives of this group in the Early Triassic fauna of Brazil.Palaeo-Anthropology Scientific Trust; French Embassy in South Africa; Co-operation and Cultural Service

    Clinical efficacy of β-lactam/β-lactamase inhibitor combinations for the treatment of bloodstream infection due to extended-spectrum β-lactamase- producing Enterobacteriaceae in haematological patients with neutropaenia: a study protocol for a retrospect observational study (BICAR).

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    Introduction: Bloodstream infection (BSI) due to extended-spectrum β-lactamase-producing Gram- negative bacilli (ESBL-GNB) is increasing at an alarming pace worldwide. Although β-lactam/β- lactamase inhibitor (BLBLI) combinations have been suggested as an alternative to carbapenems for the treatment of BSI due to these resistant organisms in the general population, their usefulness for the treatment of BSI due to ESBL-GNB in haematological patients with neutropaenia is yet to be elucidated. The aim of the BICAR study is to compare the efficacy of BLBLI combinations with that of carbapenems for the treatment of BSI due to an ESBL-GNB in this population. Methods and analysis: A multinational, multicentre, observational retrospective study. Episodes of BSI due to ESBL-GNB occurring in haematological patients and haematopoietic stem cell transplant recipients with neutropaenia from 1 January 2006 to 31 March 2015 will be analysed. The primary end point will be case- fatality rate within 30 days of onset of BSI. The secondary end points will be 7-day and 14-day case- fatality rates, microbiological failure, colonisation/ infection by resistant bacteria, superinfection, intensive care unit admission and development of adverse events. Sample size: The number of expected episodes of BSI due to ESBL-GNB in the participant centres will be 260 with a ratio of control to experimental participants of 2. Ethics and dissemination: The protocol of the study was approved at the first site by the Research Ethics Committee (REC) of Hospital Universitari de Bellvitge. Approval will be also sought from all relevant RECs. Any formal presentation or publication of data from this study will be considered as a joint publication by the participating investigators and will follow the recommendations of the International Committee of Medical Journal Editors (ICMJE). The study has been endorsed by the European Study Group for Bloodstream Infection and Sepsis (ESGBIS) and the European Study Group for Infections in Compromised Hosts (ESGICH).Ministerio de Economía y Competitividad REIPI RD12/001

    The pre-eminence of the Karoo Basin in the knowledge of the Permo-Jurassic cynodonts: A historical synthesis and taxonomical quantification

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    The search for the ancestors of mammals is historically connected with the extensive Karoo Basin of South Africa. This is because the Karoo features some of the largest exposures of Permo-Jurassic terrestrial deposits in the world and fossil discoveries were made here early in the history of palaeontology. Among the mammal-like lineages that are well-represented in Karoo fossil assemblages are the cynodonts. Originally conceived as a group exclusively containing fossil taxa, Cynodontia was subsequently redefined to include living mammals, and its Permian and early Mesozoic members are now referred to as non-mammaliaform cynodonts. Here we present a historical account of the research programme on non-mammaliaform cynodonts in the Karoo Basin, which represent the most important record of this group in the world. It covers a time spanning from the first named species in 1859 until the present day, which we arbitrarily divided into three periods: the Early Period extending from 1859 until 1932, the Second Period from 1933 to 1982, and theCurrent Period from 1983 until now. In the context of the global record of named species, we present quantitative analyses documenting the total number of nominal non-mammaliaform cynodont species from the Karoo (including junior synonyms and homonyms) as well as numerical comparison with taxa currently considered valid. Lastly, we compare the record of non-mammaliaform cynodont species from South Africa with other places in the world, such as Argentina and Brazil, which also have a diverse record of this group.Fil: Abdala, Nestor Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; Argentina. University of the Witwatersrand; SudáfricaFil: Hendrickx, Christophe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; ArgentinaFil: Jasinoski, Sandra C.. University of the Witwatersrand; SudáfricaFil: Gaetano, Leandro Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; Argentina. University of the Witwatersrand; SudáfricaFil: Liu, Jun. Chinese Academy of Sciences; República de Chin

    QTc interval and ventricular action potential prolongation in the Mecp2Null/+ murine model of Rett syndrome

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    Rett Syndrome (RTT) is a congenital, X‐chromosome‐linked developmental disorder characterized by developmental delay, dysautonomia, and breathing irregularities. RTT is also associated with sudden death and QT intervals are prolonged in some RTT patients. Most individuals with RTT have mutations in the MECP2 gene. Whilst there is some evidence for QT prolongation in mouse models of RTT, there is comparatively little information on how loss of Mecp2 function affects ventricular action potentials (APs) and, to‐date, none on ventricular APs from female RTT mice. Accordingly, the present study was conducted to determine ECG and ventricular AP characteristics of Mecp2 ( Null/+ ) female mice. ECG recordings from 12–13 month old female Mecp2 ( Null/+ ) mice showed prolonged rate corrected QT (QTc) intervals compared to wild‐type (WT) controls. Although Mecp2 ( Null/+ ) animals exhibited longer periods of apnoea than did controls, no correlation between apnoea length and QT(c) interval was observed. Action potentials (APs) from Mecp2 ( Null/+ ) myocytes had longer APD(90) values than those from WT myocytes and showed augmented triangulation. Application of the investigational I(Na,Late) inhibitor GS‐6615 (eleclazine; 10 μM) reduced both APD(90) and AP triangulation in Mecp2 ( Null/+ ) and WT myocytes. These results constitute the first direct demonstration of delayed repolarization in Mecp2 ( Null/+ ) myocytes and provide further evidence that GS‐6615 may have potential as an intervention against QT prolongation in RTT

    Delayed Ventricular Repolarization and Sodium Channel Current Modification in a Mouse Model of Rett Syndrome

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    Rett syndrome (RTT) is a severe developmental disorder that is strongly linked to mutations in the MECP2 gene. RTT has been associated with sudden unexplained death and ECG QT interval prolongation. There are mixed reports regarding QT prolongation in mouse models of RTT, with some evidence that loss of Mecp2 function enhances cardiac late Na current, I(Na,Late). The present study was undertaken in order to investigate both ECG and ventricular AP characteristics in the Mecp2(Null/Y) male murine RTT model and to interrogate both fast I(Na) and I(Na,Late) in myocytes from the model. ECG recordings from 8–10-week-old Mecp2(Null/Y) male mice revealed prolongation of the QT and rate corrected QT (QTc) intervals and QRS widening compared to wild-type (WT) controls. Action potentials (APs) from Mecp2(Null/Y) myocytes exhibited longer APD(75) and APD(90) values, increased triangulation and instability. I(Na,Late) was also significantly larger in Mecp2(Null/Y) than WT myocytes and was insensitive to the Nav1.8 inhibitor A-803467. Selective recordings of fast I(Na) revealed a decrease in peak current amplitude without significant voltage shifts in activation or inactivation V(0.5). Fast I(Na) ‘window current’ was reduced in RTT myocytes; small but significant alterations of inactivation and reactivation time-courses were detected. Effects of two I(Na,Late) inhibitors, ranolazine and GS-6615 (eleclazine), were investigated. Treatment with 30 µM ranolazine produced similar levels of inhibition of I(Na,Late) in WT and Mecp2(Null/Y) myocytes, but produced ventricular AP prolongation not abbreviation. In contrast, 10 µM GS-6615 both inhibited I(Na,Late) and shortened ventricular AP duration. The observed changes in I(Na) and I(Na,Late) can account for the corresponding ECG changes in this RTT model. GS-6615 merits further investigation as a potential treatment for QT prolongation in RTT

    Reptile species persistence under climate change and direct human threats in north-western Argentina

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    Protected areas have been established historically in residual places where the potential for extractive uses is low, implying that places at risk are usually underprotected. Argentina is no exception,with fewprotected areas established in productive regions that are prone to conversion. Here, using reptiles as a study group and considering the most important human threats in north-westernArgentina,we estimated priority conservation areas where we expect species to persist in the face of climate change and land conversion. Protected areas cover no more than 9% of the study region, but represent less than 15% of reptile distributions. There are great opportunities for improving the conservation status in the region by protecting only 8% more of north-western Argentina, with the level of species protection inside the protected area network increasing almost four-fold, reaching 43% of species distributions on average and 59% of the distributions of threatened reptiles. Fortunately, the highest diversity of reptiles in the region does not match the places targeted for agriculture expansion. Our findings suggest that future prioritization schemes should embrace other groups that are especially diverse in the Chaco ecoregion, which overlaps with our study area.FONCYT and SECYTUNC. RL’s research has been constantly funded by CNPq (grants #308532/2014-7, 479959/2013-7, 407094/2013-0 and 563621/2010-9), O Boticário Group Foundation for Nature Protection (grant #PROG_0008_2013) and CNCFlora. This paper is a contribution of the Brazilian Network on Global Climate Change Research funded by CNPq (grant #437167/2016-0) and FINEP (grant #01.13.0353.00). RLP acknowledges the support of the Australian Research Council

    The earliest cynodont therapsids from the Late Permian of the Karoo Basin, South Africa

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    Non-mammaliaform cynodonts were a widespread and successful group of advanced therapsids that arose in the early late Permian. The oldest described species are Charassognathus gracilis and Abdalodon diastematicus, both of which are known from single specimens from the Endothiodon Assemblage Zone (Tropidostoma-Gorgonops Subzone) of the Beaufort Group of the Main Karoo Basin, South Africa. Here we present two undescribed cynodont specimens from the same subzone, which comprise a second specimen of A. diastematicus and a new species of a small-bodied cynodont, housed at the palaeontological collections of the Council for Geosciences, Pretoria, South Africa and the Evolutionary Studies Institute, University of the Witwatersrand, Johannesburg, South Africa, respectively. Three of these four early cynodont specimens, excluding Charassognathus, were CT scanned using a Nikon Metrology XTH 225/320 LC dual source industrial CT system at the Evolutionary Studies Institute at the University of the Witwatersrand (Johannesburg, South Africa), enhancing the assessment of their craniodental morphology. Remarkable features of the new species include: the presence of a platform on the dentary, lateral to the lower postcanines; the absence of a masseteric fossa; two forms of sectorial postcanine teeth, whereby the anterior postcanines possess a posterior accessory cusp and the posterior postcanines have an additional anterior accessory cusp; and the presence of two small, canine-like postcanines in the dentary immediately distal to the canines. X-ray images of the new material of A. diastematicus suggest alternating dental replacement of the complex upper postcanines, which also seems to be the case for the lower incisors. A preliminary phylogeny retrieves Abdalodon as closely related to a monophyletic clade formed by the cosmopolitan Procynosuchus and the Russian Dvinia, whereas the new taxon and Charassognathus are successive sister species of remaining cynodonts.Fil: Abdala, Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; ArgentinaFil: Benoit, Julien. University of the Witwatersrand; SudáfricaFil: Jasinoski, Sandra C.. University of the Witwatersrand; SudáfricaFil: Gaetano, Leandro Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Day, Michael O.. National Museum of Natural History; Estados UnidosFil: Rubidge, Bruce S.. University of the Witwatersrand; SudáfricaXII Congreso de la Asociación Paleontológica ArgentinaArgentinaAsociación Paleontológica Argentin
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