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Digestive alfa-amylases from Tecia solanivora larvae (Lepidoptera: Gelechiidae): response to pH, temperature and plant amylase inhibitors.

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Germinación De Semillas De Asclepias Subulata En Condiciones De Casa Sombra Utilizando Ácido Giberélico

The objective of this work was to evaluate the use of gibberellic acid (GA3) in the seed germination of Asclepias subulata Decne., plant of the wild flora of the Sonoran Desert of interest for reforestation, industry and medicinal use. Since there is no information about their domestication, it is of fundamental importance to carry out germination tests to ensure their propagation, given the low germination percentage that this species presents. Seeds of A. subulata were collected in the Sonoran Desert, within the area known as Cerro del Bachoco. Six concentrations of gibberellic acid (GA3) (0, 125, 250, 500, 1000 and 2000 ppm) were tested at two soak times (24 and 48 hours) and one control without any treatment. Germination power, germination time at 25, 50 and 75%, and the germination rate index were evaluated. Germination was considered when the seed emits the hypocotyl outside the substrate used. Chemical scarification with GA3 has a positive influence on seed germination of A. subulata. The highest percentage of germination was obtained with GA3 in concentrations of 250 to 2000 ppm, at 24 and 48 hours of soaking. Germination time was affected by the concentration of GA3, being favored at a concentration of 1000 and 2000 ppm at 24 and 48 hours of soaking; while in other treatments 75% of germination was not reached. Chemical scarification with GA3 favored the germination rate index

Diversidad y estructura de un robledal en la reserva biológica Cachalú, Encino (Santander­Colombia)

We analyzed diversity, structure and preliminary plant dynamics features (mortality and recruitment) of a one ha permanent plot in an oak forest, at the Reserva Biológica Cachalú, at an altitude of between 2100 and 2200 m. The plot was established in 2007, when all plant individuals with dbh 10 cm (irst category) were tagged, measured and plotted. All individuals 1 and 10 cm dbh (second category) were sampled in an area of 0.2 ha within the plot. In the last census (July 2009), we found 453 individuals, 23 families, 26 genera and 34 species from the irst Category and 624 individuals, 34 families, 60 genera and 80 species from the second. The species-area curve showed a value of R2= 0.97. According to the structure analysis, most of the individuals, mainly treelets, were accumulated in the irst diameter, showing an up-turned "J" distribution, which illustrates early forest stages. Between the plot establishment and the irst census (1.5 yr) the basal area of the irst category decreased 1.61% while the second increased 36.6%. The most important species according to IVI were Quercus humboldtii, Clusia schomburgkiana and Blakea cuatrecasii. Mortality and recruitment rates for the irst category were 0.96% y 1%, respectively and in the second category these values were 2.8% y 12.2% respectively. During 1.5 yr new gaps appeared within the plot, which is associated with the decrease in total basal area. Despite high similarity in species composition compared with other neotropical montane forests, the dynamics and structure of the community in the present study appear to be distinct.Se analiza la diversidad, la estructura y los aspectos relacionados con la dinámica (datos preliminares de mortalidad y de reclutamiento) de un robledal, provenientes de una parcela permanente de 1 ha, en la Reserva Biológica Cachalú, entre 2100 y 2200 m de altitud. Durante el establecimiento en el 2007 se marcaron, midieron y mapearon los individuos con DAP10 cm (primera categoría), y en 0.2 ha con 1 DAP 10 cm (segunda categoría). Durante el primer censo (julio de 2009) se encontraron 453 individuos, 34 especies, 26 géneros y 23 familias en la primera categoría y 624 individuos, 80 especies, 60 géneros y 34 familias en la segunda. La curva especies-área mostró un valor R2=0.97. En estructura, la distribución de diámetros tuvo una evidente acumulación de individuos en las primeras clases de tamaño que en su mayoría corresponden a arbolitos, mostrando una distribución de "J" invertida, lo cual evidencia los estados tempranos de crecimiento del bosque. Entre el establecimiento y el primer censo realizado (1.5 años) se encontró que el área basal disminuyó 1.61% (13.99 m2ha-1 a 13.76 m2ha-1) en la primera categoría y aumentó 36.96% (0.51 a 0.70 m2) en la segunda. Las especies más importantes de acuerdo al IVI fueron Quercus humboldtii, Clusia schomburgkiana y Blakea cuatrecasii. Las tasas de mortalidad y reclutamiento fueron de 0.96% y 1%, en la primera categoría y de 2.80% y 12.20% en la segunda. Durante este periodo de tiempo se presentaron nuevos claros en la parcela, lo cual se releja en la disminución del área basal total. A pesar de la similitud lorística del robledal estudiado con otros bosques montanos neotropicales, diieren algunas características estructura y de dinámica

Abundancia del gato montés (Lynx rufus escuinapae J. A. Allen, 1903) en el Parque Nacional el Cimatario, Querétaro, México

Bobcat conservation status in central Mexico remains unclear. In many localities it is possible that bobcat populations are declining, so it is very important to estimate the densities of this species. In this note we report an abundance of 3 ± 0.78 bobcats and a minimum density of 0.17 ind/km2 at the Parque Nacional El Cimatario, Querétaro. Information on the species is limited and this data are needed to improve our knowledge in fragmented landscapes

Role of AGAP2 in the profibrogenic effects induced by TGFβ in LX-2 hepatic stellate cells

Liver damage induces hepatic stellate cells (HSC) activation, characterised by a fibrogenic, proliferative and migratory phenotype. Activated HSC are mainly regulated by transforming growth factor β 1 (TGFβ1), which increases the production of extracellular matrix proteins (e.g. collagen-I) promoting the progression of hepatic fibrosis. AGAP2 (ArfGAP with GTPase domain, ankyrin repeat and PH domain 2) is a GTPase/GTP-activating protein involved in the actin remodelling system and receptor recycling. In the present work the role of AGAP2 in human HSC in response to TGFβ1 was investigated. LX-2 HSC were transfected with AGAP2 siRNA and treated with TGFβ1. AGAP2 knockdown prevented to some extent the proliferative and migratory TGFβ1-induced capacities of LX-2 cells. An array focused on human fibrosis revealed that AGAP2 knockdown partially prevented TGFβ1-mediated gene expression of the fibrogenic genes ACTA2, COL1A2, EDN1, INHBE, LOX, PDGFB, TGFΒ12, while favored the expression of CXCR4, IL1A, MMP1, MMP3 and MMP9 genes. Furthermore, TGFβ1 induced AGAP2 promoter activation and its protein expression in LX-2. In addition, AGAP2 silencing affected TGFβ1-receptor 2 (TGFR2) trafficking in U2OS cells, blocking its effective recycling to the membrane. AGAP2 silencing in LX-2 cells prevented the TGFβ1-induced increase of collagen-I protein levels, while its over-expression enhanced collagen I protein expression in the presence or absence of the cytokine. AGAP2 overexpression also increased focal adhesion kinase (FAK) phosphorylated levels in LX-2 cells. FAK and MEK1 inhibitors prevented the increase of collagen-I expression caused by TGFβ1 in LX-2 overexpressing AGAP2. In summary, the present work shows for the first time, that AGAP2 is a potential new target involved in TGFβ1 signalling, contributing to the progression of hepatic fibrosis

Improving zebrafish embryo xenotransplantation conditions by increasing incubation temperature and establishing a proliferation index with ZFtool

Background Zebrafish (Danio rerio) is a model organism that has emerged as a tool for cancer research, cancer being the second most common cause of death after cardiovascular disease for humans in the developed world. Zebrafish is a useful model for xenotransplantation of human cancer cells and toxicity studies of different chemotherapeutic compounds in vivo. Compared to the murine model, the zebrafish model is faster, can be screened using high-throughput methods and has a lower maintenance cost, making it possible and affordable to create personalized therapies. While several methods for cell proliferation determination based on image acquisition and quantification have been developed, some drawbacks still remain. In the xenotransplantation technique, quantification of cellular proliferation in vivo is critical to standardize the process for future preclinical applications of the model. Methods This study improved the conditions of the xenotransplantation technique – quantification of cellular proliferation in vivo was performed through image processing with our ZFtool software and optimization of temperature in order to standardize the process for a future preclinical applications. ZFtool was developed to establish a base threshold that eliminates embryo auto-fluorescence and measures the area of marked cells (GFP) and the intensity of those cells to define a ‘proliferation index’. Results The analysis of tumor cell proliferation at different temperatures (34 °C and 36 °C) in comparison to in vitro cell proliferation provides of a better proliferation rate, achieved as expected at 36°, a maintenance temperature not demonstrated up to now. The mortality of the embryos remained between 5% and 15%. 5- Fluorouracil was tested for 2 days, dissolved in the incubation medium, in order to quantify the reduction of the tumor mass injected. In almost all of the embryos incubated at 36 °C and incubated with 5-Fluorouracil, there was a significant tumor cell reduction compared with the control group. This was not the case at 34 °C. Conclusions Our results demonstrate that the proliferation of the injected cells is better at 36 °C and that this temperature is the most suitable for testing chemotherapeutic drugs like the 5-FluorouracilThis research was funded by the Fondo de Investigación Sanitaria (Instituto Carlos III) - FIS project (PI13/01388). The funding body had no role in the design of the study and collection, analysis, and interpretation of data and in writing of this manuscriptS

Mejora en el conocimiento y la ansiedad de los cuidadores del paciente con traqueostomía después de asesoría personalizada

Se propuso evaluar el efecto de la asesoría personalizada en el nivel de conocimientos y el grado de ansiedad de los cuidadores de pacientes con traqueostomía. Estudio pre-experimental en 12 cuidadores, a los cuales se les impartió asesoría personalizada con cinco sesiones a disponibilidad del tiempo del cuidador. Se aplicó un cuestionario de conocimientos y la escala de ansiedad de Hamilton