Genetic Mouse Models as In Vivo Tools for Cholangiocarcinoma Research

Cholangiocarcinoma (CCA) is a genetically and histologically complex disease with a highly dismal prognosis. A deeper understanding of the underlying cellular and molecular mechanisms of human CCA will increase our current knowledge of the disease and expedite the eventual development of novel therapeutic strategies for this fatal cancer. This endeavor is effectively supported by genetic mouse models, which serve as sophisticated tools to systematically investigate CCA pathobiology and treatment response. These in vivo models feature many of the genetic alterations found in humans, recapitulate multiple hallmarks of cholangiocarcinogenesis (encompassing cell transformation, preneoplastic lesions, established tumors and metastatic disease) and provide an ideal experimental setting to study the interplay between tumor cells and the surrounding stroma. This review is intended to serve as a compendium of CCA mouse models, including traditional transgenic models but also genetically flexible approaches based on either the direct introduction of DNA into liver cells or transplantation of pre-malignant cells, and is meant as a resource for CCA researchers to aid in the selection of the most appropriate in vivo model system

Genetic mouse models as in vivo tools for cholangiocarcinoma research

Cholangiocarcinoma (CCA) is a genetically and histologically complex disease with a highly dismal prognosis. A deeper understanding of the underlying cellular and molecular mechanisms of human CCA will increase our current knowledge of the disease and expedite the eventual development of novel therapeutic strategies for this fatal cancer. This endeavor is effectively supported by genetic mouse models, which serve as sophisticated tools to systematically investigate CCA pathobiology and treatment response. These in vivo models feature many of the genetic alterations found in humans, recapitulate multiple hallmarks of cholangiocarcinogenesis (encompassing cell transformation, preneoplastic lesions, established tumors and metastatic disease) and provide an ideal experimental setting to study the interplay between tumor cells and the surrounding stroma. This review is intended to serve as a compendium of CCA mouse models, including traditional transgenic models but also genetically flexible approaches based on either the direct introduction of DNA into liver cells or transplantation of pre-malignant cells, and is meant as a resource for CCA researchers to aid in the selection of the most appropriate in vivo model system

Spalling uniaxial strength of Al2O3 at high strain rates

In this article research into the uniaxial tensile strength of Al2O3 monolithic ceramic is presented. The experimental procedure of the spalling of long bars is investigated from different approaches. This method is used to obtain the tensile strength at high strain rates under uniaxial conditions. Different methodologies proposed by several authors are used to obtain the tensile strength. The hypotheses needed for the experimental set-up are also checked, and the requirements of the set-up and the variables are also studied by means of numerical simulations. The research shows that the shape of the projectile is crucial to achieve successfully tests results. An experimental campaign has been carried out including high speed video and a digital image correlation system to obtain the tensile strength of alumina. Finally, a comparison of the test results provided by three different methods proposed by different authors is presented. The tensile strength obtained from the three such methods on the same specimens provides contrasting results. Mean values vary from one method to another but the trends are similar for two of the methods. The third method gives less scatter, though the mean values obtained are lower and do not follow the same trend as the other methods for the different specimens

Yield and nutritional value of first-cutting alfalfa grown in temperature gradient greenhouses under future climate change scenarios depend on Sinorhizobium meliloti strain

Ponencia presentada a la 51 Reunión Científica de la SEEP celebrada en la Escuela Superior de Ingenieros Agrónomos de la Universidad Pública de Navarra entre el 14 y el 18 de mayo de 2012.El objetivo del estudio fue analizar bajo distintos escenarios de simulación de cambio climático (CO2 y temperatura elevados), el efecto de tres cepas de Sinorhizobium meliloti, en la producción, calidad y digestibilidad in-vitro de la alfalfa. Las alfalfas más productivas en su primer corte durante el mes de noviembre fueron las inoculadas con la cepa 102F34, seguidas por la 102F78 y la 1032GMI. El CO2 y la temperatura elevados aumentaron el contenido en fibras, disminuyendo la digestibilidad invitro de la materia seca en las plantas inoculadas con las cepas 102F78 y 1032GMI. La proteína bruta, un indicador de la calidad del forraje, descendió en condiciones de CO2 y temperatura elevados, independientemente de la cepa inoculada. Si bien las plantas inoculadas con la cepa 102F78 produjeron forraje con mayor concentración de proteína bruta, la mayor digestibilidad obtenida con la cepa 102F34, hizo que de las tres cepas analizadas, sea ésta la más adecuada en el escenario de cambio climático estudiado.Elevated CO2 may decrease alfalfa forage quality and in-vitro digestibility through a drop in crude protein and an enhancement of fibre content. The aim of the present study was to analyze the effect of elevated CO2, elevated temperature and Sinorhizobium meliloti strains on alfalfa yield, forage quality and in-vitro dry matter digestibility. Shoot dry matter under elevated CO2 and temperature was different depending on the S. meliloti strain, with 102F34 inoculated plants being the most productive, followed by 102F78, and then 1032GMI. Plants inoculated with the 102F34 strain did not enhance neutral or acid detergent fibre under elevated CO2 or temperature and hence, in-vitro dry matter digestibility was unaffected. Crude protein content, an indicator of forage quality, was negatively related to shoot yield. Plants inoculated with 102F78 showed a similar shoot yield to those inoculated with 102F34, but had higher crude protein content at elevated CO2 and temperature. Under these climate change conditions, 102F78 inoculated plants produced more quality forage. However, the higher digestibility of plants inoculated with the 102F34 strain under any CO2 or temperature conditions, makes them more suitable for growing under applied experimental climate change conditions.Ministerio de Ciencia e Innovación (MICINN BFU2008-01405 y BFU2011-26989), Fundación Universitaria de Navarra (PIUNA-2008), Fundación Caja Navarra y Asociación de Amigos de la Universidad de Navarra

Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV

The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8  TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum