Sex differences in the inflammatory response of primary astrocytes to lipopolysaccharide

<p>Abstract</p> <p>Background</p> <p>Numerous neurological and psychiatric disorders show sex differences in incidence, age of onset, symptomatology or outcome. Astrocytes, one of the glial cell types of the brain, show sex differences in number, differentiation and function. Since astrocytes are involved in the response of neural tissue to injury and inflammation, these cells may participate in the generation of sex differences in the response of the brain to pathological insults. To explore this hypothesis, we have examined whether male and female astrocytes show a different response to an inflammatory challenge and whether perinatal testosterone influences this response.</p> <p>Methods</p> <p>Cortical astrocyte cultures were prepared from postnatal day 1 (one day after birth) male or female CD1 mice pups. In addition, cortical astrocyte cultures were also prepared from female pups that were injected at birth with 100 μg of testosterone propionate or vehicle. Cultures were treated for 5 hours with medium containing lipopolysaccharide (LPS) or with control medium. The mRNA levels of IL6, interferon-inducible protein 10 (IP10), TNFα, IL1β, Toll-like receptor 4 (TLR4), steroidogenic acute regulatory protein and translocator protein were assessed by quantitative real-time polymerase chain reaction. Statistical significance was assessed by unpaired <it>t</it>-test or by one-way analysis of variance followed by the Tukey <it>post hoc </it>test.</p> <p>Results</p> <p>The mRNA levels of IL6, TNFα and IL1β after LPS treatment were significantly higher in astrocytes derived from male or androgenized females compared to astrocytes derived from control or vehicle-injected females. In contrast, IP10 mRNA levels after LPS treatment were higher in astrocytes derived from control or vehicle-injected females than in those obtained from males or androgenized females. The different response of male and female astrocytes to LPS was due neither to differences in the basal expression of the inflammatory molecules nor to differences in the expression of the LPS receptor TLR4. In contrast, the different inflammatory response was associated with increased mRNA levels of translocator protein, a key steroidogenic regulator, in female astrocytes that were treated with LPS.</p> <p>Conclusions</p> <p>Male and female cortical astrocytes respond differentially to an inflammatory challenge and this may be predetermined by perinatal testosterone exposure.</p

Experimental determination of surface heat transfer coefficient in a dry ice-ethanol cooling bath using a numerical approach

Background: Dry ice-ethanol bath (-78ºC) have been widely used in low temperature biological research to attain rapid cooling of samples below freezing temperature. The prediction of cooling rates of biological samples immersed in dry ice-ethanol bath is of practical interest in cryopreservation. The cooling rate can be obtained using mathematical models representing the heat conduction equation in transient state. Additionally, at the solid cryogenic-fluid interface, the knowledge of the surface heat transfer coefficient (h) is necessary for the convective boundary condition in order to correctly establish the mathematical problem. Objective: The study was to apply numerical modeling to obtain the surface heat transfer coefficient of a dry ice-ethanol bath. Materials and methods: A numerical finite element solution of heat conduction equation was used to obtain surface heat transfer coefficients from measured temperatures at the center of polytetrafluoroethylene and polymethylmetacrylate cylinders immersed in a dry ice-ethanol cooling bath. The numerical model considered the temperature dependence of thermophysical properties of plastic materials used. Results: A negative linear relationship is observed between cylinder diameter and heat transfer coefficient in the liquid bath, the calculated h values were 308, 135 and 62.5 W/(m2K) for PMMA 1.3, PTFE 2.59 and 3.14 cm in diameter, respectively. Conclusion: The calculated heat transfer coefficients were consistent among several replicates; h in dry ice-ethanol showed an inverse relationship with cylinder diameter.Centro de Investigación y Desarrollo en Criotecnología de Alimento

Blast Effects on Structural Elements

Blast loads can represent a great hazard to existing structures. Their effects on structural elements can be decisive for the integrity of both the structure itself and the people within it. The behaviour of the individual elements of a building is totally different due to the heterogeneity of the materials composing them. This fact makes it necessary to carry out tests on each type of structural element in order to correctly evaluate the response of the structure. In addition, the scale effect can produce inaccurate results, making it necessary for tests to be performed on a full scale to validate the results. In this work, the results of several tests with explosives are presented, in different constructive elements, all of them carried out at full scale. These elements range from the structural elements (beams and concrete slabs) to the weak elements of a building (masonry panels)

Recordando a mujeres relevantes de la historia y cultura escocesas

[Resumen] Esta Mesa Redonda aborda el estudio de algunas mujeres que jugaron un papel relevante en la sociedad escocesa de su tiempo y que han pasado a ocupar, por méritos propios, un lugar en destacado en su historia y cultura de Escocia. Nos vamos a centrar en sus biografías y en su contribución al desarrollo de la nación escocesa, así como en la proyección que todas ellas han tenido a nivel internacional

Interplay between symmetry and spin-orbit coupling on graphene nanoribbons

We study the electronic structure of chiral and achiral graphene nanoribbons with symmetric edges, including curvature and spin-orbit effects. Curved ribbons show spin-split bands, whereas flat ribbons present spin-degenerate bands. We show that this effect is due to the breaking of spatial inversion symmetry in curved graphene nanoribbons, while flat ribbons with symmetric edges possess an inversion center, regardless of their having chiral or achiral edges. We find an enhanced edge-edge coupling and a substantial gap in narrow chiral nanoribbons, which is not present in zigzag ribbons of similar width. We attribute these size effects to the mixing of the sublattices imposed by the edge geometry, yielding a behavior of chiral ribbons that is distinct from those with pure zigzag edges. © 2013 American Physical Society.This work has been partially supported by the Spanish Ministries of Science and Innovation (MICINN) and Economy and Competitivity (MINECO) DGES under Grants No. MAT2009-14578-C03-03, No. PIB2010BZ-00512, No. FIS2010-21282-C02-02, No. FIS2011-23713, No.MAT2012-38045-C04-04, and No. FIS2012-33521.Peer Reviewe

Las muletillas y el desarrollo de la competencia estratégica oral en el aprendizaje de las lenguas extranjeras

A lot of research has been carried out on how students go about developing communicative competence when learning foreign languages. However, little do we know about how foreign language teachers help their learners to develop oral strategies that will enable them to cope with speaking problems on the fly and beyond the FL classroom. In this article we focused on a single oral communicative strategy that, we argue, has been neglected, in general, in foreign language classrooms. We present the findings of a research that focused on teaching fillers in FL classrooms in different teaching contexts and various FL classes.Se ha investigado bastante sobre cómo los estudiantes desarrollan la competencia comunicativa durante el aprendizaje de lenguas extranjeras (LEs). Sin embargo, se sabe muy poco sobre cómo los profesores ayudan a sus estudiantes a desarrollar estrategias orales que les permitan enfrentar problemas que surgen en el momento de la comunicación y más allá del aula. En este artículo presentamos y discutimos los resultados de una investigación acerca de la enseñanza de las muletillas en clases de LEs en diferentes contextos educativos. Se concluye que la enseñanza de las muletillas ha sido descuidada en gran medida en los salones de lenguas extranjeras

Biodiversidad y especiación críptica en los caprélidos (Crustacea: Amphipoda): ¿cuánto falta por descubrir?

La biodiversidad en el medio marino está subestimada, particularmente en el caso de los invertebrados donde la presencia de especies crípticas es más frecuente de lo que se pensaba. Los anfípodos caprélidos, a pesar de su importancia en el medio marino, han sido muy poco estudiados, y esto se debe, en gran parte, a su complicada taxonomía. Así mismo, la tradicional identificación taxonómica basada en caracteres morfológicos sigue siendo la más empleada para identificar y describir las especies de caprélidos, y, dado que la especiación no siempre va acompañada de cambio morfológico (especies crípticas), el uso exclusivo de estos caracteres puede conllevar a una subestimación de su diversidad real. El empleo de metodologías complementarias es, por tanto, necesario. Y, en este sentido, las herramientas moleculares han resultado eficaces y útiles para identificar especies y resolver problemas taxonómicos en estos pequeños crustáceos marinos. En el presente trabajo se muestra una pequeña revisión de los resultados obtenidos para diferentes especies del género Caprella. Estos resultados, que muestran la existencia de nuevas especies, muchas de ellas crípticas, indican que la diversidad de los caprélidos está subestimada, y que la especiación críptica parece ser un fenómeno muy importante y frecuente en estos organismos.Fondo Europeo de Desarrollo Regional POCTI/BSE/42300/2001, FCOMP-01- 0124-FEDER-PTDC/MAR/118205/201

Desnaturalización de alta resolución para estudio de marcadores moleculares asociados a obesidad

El objetivo del presente trabajo fue determinar la utilidad de la técnica de “High Resolution Melting” (HRM) como método para identificar variantes en genes asociados al desarrollo de obesidad en niños

Rapid decrease in titer and breadth of neutralizing anti-HCV antibodies in HIV/HCV-coinfected patients who achieved SVR

The main targets for neutralizing anti-hepatitis C virus (HCV) antibodies (HCV-nAbs) are the E1 and E2 envelope glycoproteins. We have studied the characteristics of HCV-nAbs through a retrospective study involving 29 HIV/HCV-coinfected patients who achieved sustained virological response (SVR) with pegIFNα+ribavirin anti-HCV therapy. Plasma samples at baseline and week 24 after SVR were used to perform neutralization assays against fve JFH1-based HCV recombinant viruses coding for E1 and E2 from genotypes 1a (H77), 1b (J4), 2a (JFH1), 3a (S52) and 4a (ED43). At baseline, the majority of plasma samples neutralized 1a, 1b, 2a, and 4a, but not 3a, genotypes. Twenty-four weeks following SVR, most neutralizing titers declined substantially. Furthermore, titers against 3a and 2a were not detected in many patients. Plasma samples with high HCV-nAb titers neutralized all genotypes, and the highest titers at the starting point correlated with the highest titers at week 24 after SVR. In conclusion, high titers of broad-spectrum HCV-nAbs were detected in HIV/HCV-coinfected individuals, however, those titers declined soon after SVRThis study was supported by grants from Instituto de Salud Carlos III (ISCIII; grant numbers PI14/01094 and PI17/00657 to JB, PI17/00903 to JGG, PI14CIII/00011 and PI17CIII/00003 to SR) and Ministerio de Sanidad, Servicios Sociales e Igualdad (grant number EC11-241). Te study was also funded by the RD16CIII/0002/0002, RD16/0025/0018, and RD16/0025/0017 projects as part of the Plan Nacional R+D+I and co-funded by ISCIII- Subdirección General de Evaluación and the Fondo Europeo de Desarrollo Regional (FEDER

Prácticas funerarias del Antiguo Egipto

Tres momias egipcias del Museo de La Plata han sido estudiadas a través de un barrido tomográfico. Los estudios realizados permitieron conocer más acerca de las técnicas de momificación del antiguo Egipto, acerca de la época y estrato social al que pertenecían esas personas y qué enfermedades padecieron.Fundación Museo La Plat