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Impairment of lung liquid absorption can lead to severe respiratory symptoms, such as those observed in pulmonary oedema. In the adult lung, liquid absorption is driven by cation transport through two pathways: a well-established amiloride-sensitive Na(+) channel (ENaC) and, more controversially, an amiloride-insensitive channel that may belong to the cyclic nucleotide-gated (CNG) channel family. Here, we show robust CNGA1 (but not CNGA2 or CNGA3) channel expression principally in rat alveolar type I cells; CNGA3 was expressed in ciliated airway epithelial cells. Using a rat in situ lung liquid clearance assay, CNG channel activation with 1 mM 8Br-cGMP resulted in an approximate 1.8-fold stimulation of lung liquid absorption. There was no stimulation by 8Br-cGMP when applied in the presence of either 100 μM L: -cis-diltiazem or 100 nM pseudechetoxin (PsTx), a specific inhibitor of CNGA1 channels. Channel specificity of PsTx and amiloride was confirmed by patch clamp experiments showing that CNGA1 channels in HEK 293 cells were not inhibited by 100 μM amiloride and that recombinant αβγ-ENaC were not inhibited by 100 nM PsTx. Importantly, 8Br-cGMP stimulated lung liquid absorption in situ, even in the presence of 50 μM amiloride. Furthermore, neither L: -cis-diltiazem nor PsTx affected the β(2)-adrenoceptor agonist-stimulated lung liquid absorption, but, as expected, amiloride completely ablated it. Thus, transport through alveolar CNGA1 channels, located in type I cells, underlies the amiloride-insensitive component of lung liquid reabsorption. Furthermore, our in situ data highlight the potential of CNGA1 as a novel therapeutic target for the treatment of diseases characterised by lung liquid overload.

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Concerns have increased regarding the detection of endocrine-disrupting compounds in the effluents of sewage treatment plants (STPs). These compounds are able to disrupt normal function of the endocrine system of living organisms even at trace concentrations. Natural and synthetic steroid estrogens (SEs) are believed to be responsible for the majority of the endocrine-disrupting effects. Municipal sewage, the main source of SEs in the environment, is a complex mixture of a wide range of pollutants at concentrations much higher than those of SEs. Low concentrations of SEs in the presence of copollutants thus make their removal problematic. The main objectives of the present work were to study the potential of photocatalytic oxidation (PCO) to effectively treat SE-containing aqueous solutions and to identify the optimum conditions for such treatment. The results showed that SEs can be effectively degraded photocatalytically. Due to the adsorption properties of SEs on the TiO2 photocatalyst surface alkaline medium was found to be beneficial for SE oxidation despite the presence of co-pollutants in concentrations characteristic for the sanitary fraction of municipal sewage. The potential of PCO to selectively oxidise SEs was examined in the presence of copollutants of the sanitary fraction of sewage - urea, saccharose and human urine. The impact of ethanol, often used as a solvent in the preparation of SE stock solutions, was also studied and the results indicated the need to use organic solvent-free solutions for the study of SE behaviour. Photocatalytic oxidation of SEs appeared to be indifferent towards the presence of urea in concentrations commonly found in domestic sewage. The effect of other co-pollutants under consideration was far weaker than could be expected from their concentrations, which are from one hundred to a few thousands times higher than those of the SEs. Although higher concentrations can dramatically slow down the PCO of SEs, realistic concentrations of co-pollutants characteristic for the sanitary fraction of domestic sewage allowed selective removal of SEs. This indicates the potential of PCO to be a selective oxidation method for SE removal from the separate sanitary fraction of municipal sewage.

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Due to the power of genetics, the mouse has become a widely used animal model in vision research. However, its eyeball has an axial length of only about 2 mm. The present protocol describes how to easily dissect the small rodent eye post mortem. This allows collecting different tissues of the eye, i.e., cornea, lens, iris, retina, optic nerve, retinal pigment epithelium (RPE), and sclera. We further describe in detail how to process these eye samples in order to obtain high‐quality RNA for RNA expression profiling studies. Depending on the eye tissue to be analyzed, we present appropriate lysis buffers to prepare total protein lysates for immunoblot and immuno‐precipitation analyses. Fixation, inclusion, embedding, and cryosectioning of the globe for routine histological analyses (HE staining, DAPI staining, immunohistochemistry, in situ hybridization) is further presented. These basic protocols should allow novice investigators to obtain eye tissue samples rapidly for their experiments.

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Abstract Objective. We compared the prevalence of body weight categories between public and private schools in the Seychelles, a rapidly developing small island state in the African region. Methods. In 2004-2006, weight and height were measured and self-reported information on physical activity collected in children of three selected grades in all schools in the country. Overweight, obesity and thinness were defined according to standard criteria. Results. Based on 8 462 students (377 in private schools), the prevalence of overweight (including obesity) was markedly higher in private than public schools (boys: 37% [95% CI: 31-44] vs. 15% [14-16]; girls: 33% [26-41] vs. 20% [19-22]). The prevalence of thinness grade 1 was lower in private than public schools (boys: 9% [5-13] vs. 20% [19-21]; girls: 13% [8-18] vs. 19% [18-20]). Students in private schools reported more physical activity at leisure time while students in public schools reported larger weekly walking time. Conclusions. Our findings suggest that school type may be a useful indicator for assessing the association between socio-economic status and overweight in children, and that overweight affects wealthy children more often than others in developing countries.

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Este trabalho foi realizado no município de Jales, localizado na região noroeste do Estado de São Paulo, com o objetivo de analisar economicamente o cultivo da acerola para mesa. Para se estimar a matriz de coeficientes técnicos, os custos de implantação e produção e os indicadores de lucratividade da cultura, os dados foram levantados junto a um produtor e técnicos da região, em 2000. Os custos de implantação e formação da cultura nos dois primeiros anos atingiram R$2.462,09/ha, e a receita líquida estimada para a acerola a partir do 5º ano foi de R$9.061,55, correspondendo a um índice de lucratividade de 59,23%, resultado bastante atraente, principalmente para produtores interessados em diversificarem suas atividades voltadas especificamente para a fruticultura.

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O estudo do desenvolvimento das plantas relacionado com as condições climáticas de uma região permite a elaboração de modelos de previsão que podem ser úteis na programação de colheita. Esses modelos possibilitam prever o início da safra e a duração dos diferentes períodos fenológicos das plantas, assim como auxilia no manejo de práticas agrícolas. Esta pesquisa teve como objetivo estudar variedades de tangerinas do tipo Murcott enxertadas em diferentes porta-enxertos, avaliando a resposta fenológica de cada uma delas em função do acúmulo de graus-dia. O experimento foi conduzido no Centro Avançado de Pesquisa Tecnológica do Agronegócio de Citros Sylvio Moreira/IAC, localizado na cidade de Cordeirópolis-SP, durante a safra 2003-2004. O delineamento utilizado foi o de blocos casualisados e esquema fatorial 5 (variedades copas) x 3 (porta-enxertos), com 4 repetições, com uma planta por parcela. As variedades estudadas foram Thomas, Szuwinkon, Szuwinkon x Szinkon-Tizon e Sul da África, tendo como testemunha o tangor Murcott. Essas copas foram enxertadas em limoeiro Cravo, tangerineira Sunki e citrumeleiro Swingle, e plantadas em 1995. Para a caracterização fenológica, foram atribuídas notas de uma escala elaborada para os estádios fenológicos, desde o pré-florescimento até a maturação fisiológica dos frutos, determinando as datas de ocorrência das fases reprodutivas das plantas. Com isso, calculou-se o acúmulo de graus-dia para os subperíodos fenológicos. Pelas características das combinações, existem diferenças nas respostas das plantas, onde: a) o acúmulo de graus-dia, da antese até ratio 12, variou de 2.272 GD a 2.836 GD, sendo que as tangerinas Szuwinkon, Szuwinkon x Szinkon-Tizon e Sul da África obtiveram os menores valores (» 2.318 GD), a Murcott cerca de 2.462 GD e a tangerina Thomas os maiores valores (» 2.791 GD); foram observadas diferenças de 20 dias do florescimento até ratio 12, dependendo da combinação copa/porta-enxerto.

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Introduction. The current study describes the planning process and aims of the university reforms in Spain and suggests an innovative proposal, namely the design and evaluation of a week-long induction programme for first-year bachelor‟s degree students at the University of Lleida (Spain), organised within the European higher education framework. The purpose of this induction programme is to help new students adapt to university life. Method. A total of 102 students and ten lecturers were involved in the study. These participants responded questionnaires and interviews. We contrasted all the results in order to obtain some results that were useful to evaluate the induction programmee which the University introduced in the first four degrees. Results. Findings of the study revealed that participants gave very positive feedback regarding the programme, and the results also highlighted areas which could be improved. Conclusion. The new proposals clearly require a higher level of staff participation to make them work, highlighting the need for appropriate training of university staff and improving coordination with appropriate systems.

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El proceso de repoblación forestal es bastante complejo, ya que implica numerosos factores, cada uno de los cuales debe ser comprendido de forma individual, y conocidas sus relaciones con otros factores con los cuales interactúa. La forma de evaluar de manera integral el resultado de estos factores es mediante el control de calidad. La respuesta de la planta en una estación particular va a depender de la capacidad de respuesta a unas condiciones ambientales limitantes, y de la forma en como esas condiciones limitan su supervivencia y crecimiento, o bien pueden ser modificadas para mejorar su arraigo. Las actividades culturales propias de las repoblaciones (ej. proceimiento de preparación, control de la vegetación, cuidados culturales, etc.) van a influir de manera directa en el éxito de la misma. La adecuada ejecución y el control de las mismas van a permitir mejorar el éxito de las repoblaciones, pero también ayudan a identificar las causas de las perdidas producidas y, por tanto, corregir defectos que condicionan su éxito final.