Background: Cancer-associated fibroblasts (CAFs), as the activated stroma cells, contribute to tumor progression via the release of cytokines, growth factors, and hormones. However, neither the factors produced by CAFs nor the molecular mechanisms were illuminated very well in gastric cancer (GC).Methods: Immunohistochemical staining of alpha-smooth muscle actin (α-SMA) was applied to examine the number of CAFs in GC samples from 227 patients. ELISA and qRT-PCR were performed to detect the expression of interleukin 17a (IL-17a). The migration and invasion of GC cells were determined by the Transwell assay. The expressions of JAK2, STAT3, MMP-2, MMP-9, TIMP-1, and TIMP-2 were measured by western blotting. IL-17a was blocked with a polyclonal antibody, and JAK2/STAT3 signaling pathway was blocked by a specific inhibitor AG490.Results: High CAFs in GC tissues were positively correlated with advanced TNM stage and perineural invasion. Furthermore, GC patients with high CAFs in tumor tissues had an obvious worse disease-free survival (DFS) and disease-special survival (DSS). Multivariate analysis showed that high CAFs in GC tissues were an independent risk factor for DFS and DSS. CAFs expressed IL-17a significantly after GC cell co-culture. CAFs markedly enhanced the migration and invasion abilities of AGS and SGC-7901 cells.Moreover, CAFs co-culture resulted in increased levels of MMP2/9, reduced expressions of TIMP1/2, and activation of the JAK2/STAT3 signaling pathway in the GC cells. IL-17a neutralizing antibody or JAK2 inhibitor AG490 can significantly inhibit the effects of CAFs on the migration, invasion, MMP2/9, TIMP1/2, and JAK2/STAT3 pathways of GC cells.Conclusions: CAFs correlated with unfavorable clinical features and poor prognosis of GC patients. CAFs secreted IL-17a, which promoted the migration and invasion of GC cells through activating JAK2/STAT3 signaling. These results may identify IL-17a as a promising prognostic marker and therapeutic target of GC.

Ozone (O 3 ) inhibits plant gas exchange and productivity. Vapour phase (g s ) and liquid or hydraulic phase (K) conductances to water flux are often correlated as both change with environmental parameters. Exposure of cotton plants to tropospheric O 3 reduces g s through reversible short-term mechanisms and by irreversible long-term disruption of biomass allocation to roots which reduces K. We hypothesize that chronic effects of O 3 on gas exchange can be mediated by effects on K without a direct effect of O 3 on g s or carbon assimilation (A) Key-words: air pollution; allocation; dry deposition; evapotranspiration; oxidant; ozone flux; regional ozone concentrations; root-shoot communication; water relations Dodd et al. 1996;Muller et al. 1996;Puliga et al. 1996). Alternatively, the interaction could be mediated by effects of K on soil water acquisition and resulting water status of the leaf mesophyll (y m ) or epidermal (y e ) tissue in which the stomata are embedded (Fuchs & Livingston 1996;Shackel & Brinckmann 1985; Bunce 1996). Differences between y e and y m have been documented (Shackel & Brinckmann 1985), although associated stomatal control mechanisms and sensitivity to O 3 exposure have not been assessed..Rapid reductions in shoot gas exchange following exposure to O 3 may be associated with altered phloem loading (e.g. McCool & Menge 1983;McLaughlin & McConathy 1983;Mortensen & Engvild 1995;Grantz & Farrar 1999) and end-product inhibition of carbon metabolism. Reduced root system capacity may also lead to long-term reductions in carboxylase activity and gas exchange performance. Feedback from root to shoot following chronic exposure to O 3 would necessarily be long-term and slowly reversed, and would be expressed as a limit on maximal stomatal response to other environmental parameters. The potential mediation of chronic phytotoxic effects of O 3 on gas exchange by such a mechanism has not been investigated. Rapid shoot response to O 3In contrast, rapid gas exchange responses to O 3 have been well documented. In bean plants (Phaseolus vulgaris L.), stomatal conductance (g s ) was reduced within 6-12 min by 0·3-0·5 ppm O 3 (Moldau et al. 1990). While g s declined by about 50% within 3 h, the mesophyll conductance to CO 2 was unaffected. Similar apparent direct effects of O 3 on g s have been identified by Hill & Littlefield (1969) and by Amundson et al. (1987).Light-saturated carbon assimilation declined by about 25% in winter wheat (Triticum aestivum L.; Farage et al. 1991) and 40% in pea and oak (Pisum sativum L. and Quercus robur L.; Farage & Long 1995), while g s declined by about 40% (wheat, pea) and about 80% (oak) following 4 h of exposure to 0·4 ppm O 3 . This was associated with minimal effect on photosynthetic light reactions assayed as variable chlorophyll fluorescence and as quantum yield. Carboxylation capacity was reduced by about 30% (wheat, oak) to 45% (pea), consistent with O 3 -induced reductions in Rubisco protein and activity (Eckard & Pell 1995;Lehnherr et al. 1987;Pell...

Large publishing companies have been dominating scientific publishing for long, which leads to high subscription fees and inhibited access to scientific knowledge. At digital era, the opportunity of an unrestricted access appears feasible, because the cost of publishing should be low. It is no longer the readers and libraries to pay subscription fees, but scientific organizations and authors themselves who pay for the cost of having their article published. As the data shows, there is a tremendous variance of article processing charges (APC) across journals, which obviously cannot be explained by the costs. One of the explanatory variables could be reputation, but it only contributes less than 5% to the variance in APC. This study is meant to shed light on the various determinants of APC. Based on data from the OpenAPC Initiative, the Directory of Open Access Journals, the Journal Impact Factor and the Essential Science Indicators of Web of Science, we employ ANOVA and multivariate regressions. The results show that market power plays an important role to explain APCs, inter alia, through market concentration, market position of individual publishers (publisher size), and the choice of hybrid publishing model.

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A special image sampler was developed to non-destructively take leaf images of cucumber plants in greenhouse, which were grown in different nutrient conditions in order to obtain nitrogen stress to the crop. Then the correlation between nitrogen content of cucumber leaf and image property of the leaf was analyzed. The sampler is composed of eight lamps, a half sphere shell, a platform, and a window used for fixing camera. The lamps were arranged around the platform on what leafs would be placed for image-taking. The half sphere shell was over the platform to reflect the light of lamps. Since the reflected light from the shell was diffuse and symmetrical, the reflection noise of the leaf could be reduced and the high quality image could be obtained. The correlation analysis between leaf images and nitrogen contents of leaves was conducted based on RGB mode and HSI mode. In RGB mode the G weight of the image showed the highest linear correlation with the nitrogen content of the cucumber leaf than R weight and B weight, while in HSI mode the hue showed the same high linear correlation as the G weight. A new index from the G weight of RGB mode and the hue of HSI mode was suggested to estimate nitrogen content of cucumber leaf. The result shows the new index is practical.