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Axial and visibility graph analysis models are combined with GIS and Space Syntax to study the corresponding relationship between street network and specific city life in Hankou, China, based on three scales - city, district, and community, so as to interpret the hidden structure out of complex urban form through the spatial logic of street network. In this paper, a quantitative analysis is made on selected parameters in Space Syntax, including Integration, Choice, density of road, and Ht index. The result indicates that there is certain correlation among these parameters. Moreover, these parameters also present certain changing patterns along with the increase of analysis radius. The results reveal that the street network of Hankou presents a multi-hierarchical structure and spatial wholeness from all these three scales. This characteristic creates vitality and diversity while maintaining the feature of wholeness for the urban space. Research has turned out that community-scale street network performs a positive role to keep neighborhoods alive. Therefore, it is an important strategy for maintaining the vitality of urban space and realizing coordination and unification between parts and the whole. It is proposed in this paper that a good street network is a key factor for carrying forward urban context of Hankou. Undoubtedly, it is worthy of reflecting on large-scale demolition of existing urban space, especially in historical areas. Afterwards, the paper proposes a hierarchically synergetic planning strategy based on the analysis. More attention should be paid to street network to preserve diversity, continuity, and integrity, and finally archive holistically sustainable development within a city. [ABSTRACT FROM AUTHOR]

Purpose: Study the contribution of long non-coding RNAs (lncRNAs) to progression of pancreatic intraepithelial neoplasia (PanIN) to pancreatic ductal adenocarcinoma (PDAC). Methods: We explored lncRNAs profilings in PanIN cell line (SH-PAN) isolated from Pdx-1-Cre; LSL-Kras mice and PDAC cell line (DT-PCa) isolated from Pdx-1-Cre; LSL- Kras ; LSL- Tp53 mice by lncRNAs microarray, and detected expression of lncRNAs and genes in PDAC by Real-time PCR, Western blot, ChIP and immunohistochemistry. Results: Eight lncRNAs and five protein-coding genes, associated with Wnt pathway, were identified with more than five-fold changes between DT-PCa cells and SH-PAN cells. Of them, lincRNA1611 and Ppp3ca were validated significantly high expression in DT-PCa cells and in 22 of 26 fresh resected human PDAC tissues, compared to SH-PAN cells and normal pancreatic tissues, respectively. Moreover, Tp53 mutation status displayed a positive correlation with lincRNA1611 or Ppp3ca level. Immunohistochemical staining for Ppp3ca was weak or lack in 91 of 107 normal pancreatic tissues, 24 of 29 PanIN-I and 13 of 16 PanIN-II tissues, however, was strong in 10 of 27 PanIN-III and 62 of 107 PDAC tissues post operation. Conclusions: LincRNA1611 and Ppp3ca were high expression in PDAC and may serve as new potential targets for intervention of the disease. [ABSTRACT FROM AUTHOR]

We aimed to investigate the expression of microRNA-34a (miR-34a) in human gastric cancer cells and to evaluate the effects of miR-34a, acting via its gene survivin, on gastric cancer cell HGC-27 to provide potential new strategies for treating gastric cancer. In vitro cultures of the human gastric cancer cell lines MGC80-3, HGC-27, NCI-N87, and SGC-7901 and the normal human gastric epithelial cell line GES-1 were established. The expression of miR-34a in each gastric cancer cell line and GES-1 normal human gastric epithelial cell line was detected using quantitative real-time polymerase chain reaction (qRT-PCR). After the HGC-27 cells were transfected with a miR-34a mimic for 48 h, the changes in the expression levels of miR-34a were detected using qRT-PCR. The effect of miR-34a on HGC-27 cell viability was measured using a tetrazolium-based colorimetric [−(4,5)-dimethylthiahiazo-(−z-y1)-3,5-di-phenytetrazoliumromide (MTT)] assay. Flow cytometry was used to analyze the effects of miR-34a on HGC-27 cell proliferation. Annexin V/propidium iodide double staining and flow cytometry were used to analyze the effects of miR-34a on HGC-27 cell apoptosis. A Transwell invasion chamber was used to detect the effects of miR-34a on HGC-27 cell invasion. Finally, western blotting was used to analyze the effects of miR-34a on survivin protein expression. The qRT-PCR test determined that miR-34a expression in gastric cancer cells was significantly reduced compared to the normal gastric epithelial cell line GES-1 ( p < 0.01). Compared to the control group, cellular miR-34a expression levels were significantly increased in HGC-27 human gastric carcinoma cells after transfection with a miR-34a mimic for 48 h ( p < 0.01). The MTT assay demonstrated that after overexpressing miR-34a in HGC-27 cells, cellular viability was significantly reduced ( p < 0.05). Flow cytometry analysis determined that upon miR-34a overexpression, the proliferation index decreased significantly ( p < 0.05), and cellular apoptosis was significantly increased ( p < 0.01). The Transwell invasion chamber assay illustrated that after increasing the expression of miR-34a, the number of cells passing through the Transwell chamber was significantly reduced ( p < 0.01). Based on western blotting, compared with the control group, survivin protein expression levels were significantly decreased in the HGC-27 cells transfected with the miR-34a mimic for 48 h ( p < 0.01). In conclusion, the expression level of miR-34a was downregulated in human gastric cancer cell lines. miR-34a can negatively regulate survivin protein expression and inhibit gastric cancer cell proliferation and invasion. Therapeutically enhancing miR-34a expression or silencing the survivin gene may benefit patients with gastric cancer. [ABSTRACT FROM AUTHOR]