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Testosterone induces ERK and Akt phosphorylation via the membrane-initiated signaling pathways mediated by ER-alpha36, suggesting a possible involvement of ER-alpha 36 in testosterone carcinogenesis.

Abstract:The improper layout of urban public parks leads to the difference between citizens sharing or not sharing this kind of public resource, particularly in the historical districts of mountainous cities in China. The purpose of this study is to explore the spatial equity and quantitative measures of urban public parks' layouts by building a demand index of socially vulnerable groups sharing public parks based on the accessibility evaluation model. In this paper, Changting-a famous national historical and cultural city-is taken as the empirical object, then the accessibility and social equity of public parks is quantitatively measured with the aid of the field investigation method, the spatial analysis model of geographic information system (GIS) and the SPSS statistical analysis method. The results indicate that it is feasible to measure the spatial equity of urban public parks with the accessibility and demand index of socially vulnerable groups, and it can effectively characterize the rationality and social equity of urban ecological space. It shows that a degree of spatial mismatch exists between the distribution of urban public parks and that of residents, that is to say the spatial distribution of public parks is not equitable in terms of accessibility or residents' demands. Therefore, the data suggest that the spatial patterns and accessibility levels of parks in Changting County-especially the historical districts-should be further improved and perfected to achieve high levels of accessibility and equity through urban green space system planning. The paper may be used as a scientific reference for the planning and construction of ecological urban spaces. It can also provide useful decision-making guidance for urban planners in investigating, analyzing, and adjusting the distribution of public service facilities to achieve equitable outcomes, while promoting the harmonious and sustainable development of mountainous cities.

Errors in chromosome segregation or distribution may result in aneuploid embryo formation, which causes implantation failure, spontaneous abortion, genetic diseases, or embryo death. Embryonic aneuploidy occurs when chromosome aberrations are present in gametes or early embryos. To date, it is still unclear whether the spindle assembly checkpoint (SAC) is required for the regulation of mitotic cell cycle progression to ensure mitotic fidelity during preimplantation development. In this study, using overexpression and RNA interference (RNAi) approaches, we analyzed the role of SAC components (Bub3, BubR1 and Mad2) in mouse preimplantation embryos. Our data showed that overexpressed SAC components inhibited metaphase-anaphase transition by preventing sister chromatid segregation. Deletion of SAC components by RNAi accelerated the metaphase-anaphase transition during the first cleavage and caused micronuclei formation, chromosome misalignment and aneuploidy, which caused decreased implantation and delayed development. Furthermore, in the presence of the spindle-depolymerizing drug nocodazole, SAC depleted embryos failed to arrest at metaphase. Our results suggest that SAC is essential for the regulation of mitotic cell cycle progression in cleavage stage mouse embryos.

SummaryChromosome segregation in mammalian oocyte meiosis is an error-prone process, and any mistake in this process may result in aneuploidy, which is the main cause of infertility, abortion and many genetic diseases. It is now well known that shugoshin and protein phosphatase 2A (PP2A) play important roles in the protection of centromeric cohesion during the first meiosis. PP2A can antagonize the phosphorylation of rec8, a member of the cohesin complex, at the centromeres and thus prevent cleavage of rec8 and so maintain the cohesion of chromatids. SETb is a protein that physically interacts with shugoshin and inhibits PP2A activity. We thus hypothesized that SETb might regulate cohesion protection and chromosome segregation during oocyte meiotic maturation. Here we report for the first time the expression, subcellular localization and functions of SETb during mouse oocyte meiosis. Immunoblotting analysis showed that the expression level of SETb was stable from the germinal vesicle stage to the MII stage of oocyte meiosis. Immunofluorescence analysis showed SETb accumulation in the nucleus at the germinal vesicle stage, whereas it was targeted mainly to the inner centromere area and faintly localized to the interchromatid axes from germinal vesicle breakdown to MI stages. At the MII stage, SETb still localized to the inner centromere area, but could relocalize to kinetochores in a process perhaps dependent on the tension on the centromeres. SETb partly colocalized with PP2A at the inner centromere area. Overexpression of SETb in mouse oocytes caused precocious separation of sister chromatids, but depletion of SETb by RNAi showed little effects on the meiotic maturation process. Taken together, our results suggest that SETb, even though it localizes to centromeres, might not be essential for chromosome separation during mouse oocyte meiotic maturation, although its forced overexpression causes premature chromatid separation.

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The digital divide has loomed as a sustainable development issue for over two decades and there has been much research in terms of efforts to measure the digital divide from different dimensions and scales. Drawing on spatial agglomeration analysis and multiple linear regression, this paper aims to reveal the spatiotemporal pattern of the prefectural digital divide in China and its determinants. The results show that there is a significant prefectural digital divide in China that is characterized by a decline of ICT development index (IDI) values from the east to the west as well as from core cities to more peripheral ones. Cities with high IDI values are mainly concentrated in large metropolitan areas in eastern China, whereas cities with low values tend to concentrate in poverty stricken regions in central and western China. However, the digital divide has been characterized by a reduction from 2001 to 2015. The results also show that both economic and educational factors have significant influences on the prefectural digital divide in China. During the early stages, the percentage of university students, urban residential income, and the urbanization rate were key factors. However, after 2010, the adult literacy rate and rural residential income determined the digital divide.