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Estrogenic effect of dioxin-like aryl hydrocarbon receptor (AhR) agonist (PCB congener 126) in salmon hepatocytes 总被引:1,自引:0,他引:1
Previous studies have shown that aryl hydrocarbon receptor (AhR) agonists possess anti-estrogenic activities and several mechanisms have been proposed to explain the interactions between AhR and estrogen receptor (ER) signalling pathways. In the present study, we show that 3,3'4,4'5-pentachlorobiphenyl (PCB126 - a dioxin-like AhR agonist) produced estrogenic responses in the absence of ER agonist, in fish in vitro system. We exposed salmon primary hepatocytes to PCB126 (1, 10 and 50 pM) and the ER agonist nonylphenol (NP; 5 and 10 microM) singly and also in combination. Vitellogenin (Vtg) and zona radiata proteins (Zr-proteins) levels were analysed by semi-quantitative ELISA. We observed that the protein levels of Vtg and Zr-proteins were significantly induced in a concentration-specific manner in cells treated with PCB126 and NP, singly or in combination. In general, these results show a novel aspect of dioxin-like PCB effect not previously demonstrated in fish system. 相似文献
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Augustine Tanle 《GeoJournal》2014,79(5):577-590
In Ghana, studies on migration and livelihoods are mostly limited to migrants’ places of origin. This paper therefore assesses livelihood status of permanent migrants resident in the Obuasi Municipality who hail from the northern parts of Ghana. The instrument used was a survey questionnaire and the respondents were both migrants and indigenes aged 18 years and above. The findings showed no significant differences between migrants and indigenes in ownership of assets and consumer durable goods and housing quality. However, the indigenes earned relatively higher than the migrants due to access to various forms of capital and the influence of institutional structures and processes. But to the migrants, their livelihood status has improved since they have built houses, educated their children, remitted relations at home and have acquired some consumer durable goods. Improvement in the livelihood status of migrants could induce further north–south migration. There is therefore the need for government and other stakeholders to bridge the gap of unequal socio-economic development between the northern and southern parts of the country. 相似文献