Integrin-linked kinase can facilitate syncytialization and hormonal differentiation of the human trophoblast-derived BeWo cell line

<p>Abstract</p> <p>Background</p> <p>In the fusion pathway of trophoblast differentiation, stem villous cytotrophoblast cells proliferate and daughter cells differentiate and fuse with existing syncytiotrophoblast to maintain the multi-nucleated layer. Integrin-linked kinase (ILK) is highly expressed in 1st and 2nd trimester villous cytotrophoblast cells, yet barely detectable in syncytiotrophoblast, thus we examined the potential role of ILK in aiding trophoblast fusion.</p> <p>Methods</p> <p>The temporal/spatial expression and activity of ILK were determined in BeWo cells undergoing syncytialization by immunoblot and immunofluorescence analyses. BeWo cells were also transfected with pEGFP expression vectors containing wildtype or two mutant ILK cDNA constructs. The incidence of cell fusion in transfected cells grown under syncytialization conditions was then scored by the presence or absence of E-cadherin immunostaining. Beta-hCG expression in transfected cells, a marker of syncytiotrophoblast hormonal differentiation, was also similarly assessed.</p> <p>Results</p> <p>ILK catalytic activity increased and ILK began to increasingly localize to BeWo cell nuclei during syncytialization in correlation with increased pAkt and Snail protein expression. Syncytialization was also significantly elevated (p < 0.05) in BeWo cells expressing constitutively active (ca)-ILK vs cells containing empty vector or dn-ILK. Furthermore, cytoplasmic Beta-hCG expression markedly increased (p < 0.05) in cells expressing wt- and ca-ILK.</p> <p>Conclusion</p> <p>ILK-facilitated syncytialization is dependent, at least in part, on ILK catalytic activity while hormonal differentiation appears dependent on both ILK-associated protein interactions and catalytic activity. This study demonstrates that ILK plays a novel role in BeWo syncytialization and differentiation, perhaps through an ILK-Akt-Snail pathway, and implicates ILK in the same process in villous cytotrophoblasts in vivo.</p

The impact of cultural events on city image: Rotterdam, cultural capital of Europe 2001

Cities are increasingly using cultural events to improve their image, stimulate urban development and attract visitors and investment. As part of its event-led regeneration strategy, Rotterdam staged the 'Cultural Capital of Europe' event in 2001. The aims were to attract visitors and to stimulate cultural consumption among residents, while positioning Rotterdam as a cultural destination. Over 2000 questionnaire responses by resident and non-resident visitors to the Cultural Capital event were used to evaluate the image effects of the event. In depth interviews were also undertaken with policy-makers and cultural managers, to permit evaluation of survey findings in the context of richer qualitative material. The image of the city as a cultural destination did improve in 2001, but the physical and tangible elements of the city's image (modern architecture, water) and its character as the working city of the Netherlands continued to dominate. © 2004 The Editors of Urban Studies

Initial validation of ozone measurements from the High Resolution Dynamics Limb Sounder

Comparisons of the latest High Resolution Dynamics Limb Sounder (HIRDLS) ozone retrievals (v2.04.09) are made with ozonesondes, ground-based lidars, airborne lidar measurements made during the Intercontinental Chemical Transport Experiment–B, and satellite observations. A large visual obstruction blocking over 80% of the HIRDLS field of view presents significant challenges to the data analysis methods and implementation, to the extent that the radiative properties of the obstruction must be accurately characterized in order to adequately correct measured radiances. The radiance correction algorithms updated as of August 2007 are used in the HIRDLS v2.04.09 data presented here. Comparisons indicate that HIRDLS ozone is recoverable between 1 and 100 hPa at middle and high latitudes and between 1 and 50 hPa at low latitudes. Accuracy of better than 10% is indicated between 1 and 30 hPa (HIRDLS generally low) by the majority of the comparisons with coincident measurements, and 5% is indicated between 2 and 10 hPa when compared with some lidars. Between 50 and 100 hPa, at middle and high latitudes, accuracy is 10–20%. The ozone precision is estimated to be generally 5–10% between 1 and 50 hPa. Comparisons with ozonesondes and lidars give strong indication that HIRDLS is capable of resolving fine vertical ozone features (1–2 km) in the region between 1 and 50 hPa. Development is continuing on the radiance correction and the cloud detection and filtering algorithms, and it is hoped that it will be possible to achieve a further reduction in the systematic bias and an increase in the measurement range downward to lower heights (at pressures greater than 50–100 hPa)

Initial validation of ozone measurements from the High Resolution Dynamics Limb Sounder

Comparisons of the latest High Resolution Dynamics Limb Sounder (HIRDLS) ozone retrievals (v2.04.09) are made with ozonesondes, ground-based lidars, airborne lidar measurements made during the Intercontinental Chemical Transport Experiment–B, and satellite observations. A large visual obstruction blocking over 80% of the HIRDLS field of view presents significant challenges to the data analysis methods and implementation, to the extent that the radiative properties of the obstruction must be accurately characterized in order to adequately correct measured radiances. The radiance correction algorithms updated as of August 2007 are used in the HIRDLS v2.04.09 data presented here. Comparisons indicate that HIRDLS ozone is recoverable between 1 and 100 hPa at middle and high latitudes and between 1 and 50 hPa at low latitudes. Accuracy of better than 10% is indicated between 1 and 30 hPa (HIRDLS generally low) by the majority of the comparisons with coincident measurements, and 5% is indicated between 2 and 10 hPa when compared with some lidars. Between 50 and 100 hPa, at middle and high latitudes, accuracy is 10–20%. The ozone precision is estimated to be generally 5–10% between 1 and 50 hPa. Comparisons with ozonesondes and lidars give strong indication that HIRDLS is capable of resolving fine vertical ozone features (1–2 km) in the region between 1 and 50 hPa. Development is continuing on the radiance correction and the cloud detection and filtering algorithms, and it is hoped that it will be possible to achieve a further reduction in the systematic bias and an increase in the measurement range downward to lower heights (at pressures greater than 50–100 hPa).Las comparaciones de las últimas recuperaciones de ozono de High Resolution Dynamics Limb Sounder (HIRDLS) (v2.04.09) se realizan con ozonosondas, lidar terrestres, mediciones lidar aerotransportadas realizadas durante el Experimento B de transporte químico intercontinental y observaciones satelitales. Una gran obstrucción visual que bloquea más del 80 % del campo de visión de HIRDLS presenta desafíos significativos para los métodos de análisis de datos y su implementación, en la medida en que las propiedades radiativas de la obstrucción deben caracterizarse con precisión para corregir adecuadamente las radiancias medidas. Los algoritmos de corrección de radiancia actualizados en agosto de 2007 se utilizan en los datos de HIRDLS v2.04.09 presentados aquí. Las comparaciones indican que el ozono HIRDLS es recuperable entre 1 y 100 hPa en latitudes medias y altas y entre 1 y 50 hPa en latitudes bajas. Se indica una precisión superior al 10 % entre 1 y 30 hPa (HIRDLS generalmente bajo) en la mayoría de las comparaciones con mediciones coincidentes, y se indica un 5 % entre 2 y 10 hPa cuando se compara con algunos lidars. Entre 50 y 100 hPa, en latitudes medias y altas, la precisión es del 10 al 20 %. Se estima que la precisión del ozono es generalmente del 5 al 10 % entre 1 y 50 hPa. Las comparaciones con ozonosondas y lidar dan una fuerte indicación de que HIRDLS es capaz de resolver características finas de ozono vertical (1–2 km) en la región entre 1 y 50 hPa. Se continúa desarrollando la corrección de radiancia y los algoritmos de filtrado y detección de nubes, y se espera que sea posible lograr una mayor reducción en el sesgo sistemático y un aumento en el rango de medición hacia abajo a alturas más bajas (a presiones superiores a 50 –100hPa).Universidad Nacional, Costa RicaEscuela de Químic