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Background and Aims
A better understanding of the effects of human adipocytes on breast cancer cells may lead to the development of new treatment strategies. We explored the effects of adipocytes on the migration and invasion of breast cancer cells both in vitro and in vivo.Methods
To study the reciprocal effects of adipocytes and cancer cells, we co-cultured human mature adipocytes and breast cancer cells in a system devoid of heterogeneous cell-cell contact. To analyze the factors that were secreted from adipocytes and that affected the invasive abilities of breast cancer cells, we detected different cytokines in various co-culture media. To study the communication of mature adipocytes and breast cancer cells in vivo, we chose 10 metastatic pathologic samples and 10 non-metastatic pathologic samples to do immunostaining.Results
The co-culture media of human MCF-7 breast cancer cells and human mature adipocytes increased motility of MCF-7 cells. In addition, MMP-2 was remarkably up-regulated, whereas E-cadherin was down-regulated in these MCF-7 cells. Based on our co-culture medium chip results, we chose four candidate cytokines and tested their influence on metastasis individually. We found that IGFBP-2 enhanced the invasion ability of MCF-7 cells in vitro more prominently than did the other factors. In vivo, metastatic human breast tumors had higher levels of MMP-2 than did non-metastatic tumor tissue, whereas adipocytes around metastatic breast tumors had higher levels of IGFBP-2 than did adipocytes surrounding non-metastatic breast tumors.Conclusions
IGFBP-2 secreted by mature adipocytes plays a key role in promoting the metastatic ability of MCF-7 breast cancer cells. 相似文献184.
Quantifying carbon dioxide exchange and understanding the response of key environmental factors in various ecosystems are critical to understanding regional carbon budgets and ecosystem behaviors. For this study, CO2 fluxes were measured in a variety of ecosystems with an eddy covariance observation matrix between June 2012 and September 2012 in the Zhangye oasis area of Northwest China. The results show distinct diurnal variations in the CO2 fluxes in vegetable field, orchard, wetland, and maize cropland. Diurnal variations of CO2 fluxes were not obvious, and their values approached zero in the sandy desert, desert steppe, and Gobi ecosystems. Additionally, daily variations in the Gross Primary Production (GPP), Ecosystem Respiration (Reco) and Net Ecosystem Exchange (NEE) were not obvious in the sandy desert, desert steppe, and Gobi ecosystems. In contrast, the distributions of the GPP, Reco, and NEE show significant daily variations, that are closely related to the development of vegetation in the maize, wetland, orchard, and vegetable field ecosystems. All of the ecosystems are characterized by their carbon absorption during the observation period. The ability to absorb CO2 differed significantly among the tested ecosystems. We also used the Michaelis-Menten equation and exponential curve fitting methods to analyze the impact of Photosynthetically Active Radiation (PAR) on the daytime CO2 flux and impact of air temperature on Reco at night. The results show that PAR is the dominant factor in controlling photosynthesis with limited solar radiation, and daytime CO2 assimilation increases rapidly with PAR. Additionally, the carbon assimilation rate was found to increase slowly with high solar radiation. The light response parameters changed with each growth stage for all of the vegetation types, and higher light response values were observed during months or stages when the plants grew quickly. Light saturation points are different for different species. Nighttime Reco increases exponentially with air temperature. High Q10 values were observed when the vegetation coverage was relatively low, and low Q10 values occurred when the vegetables grew vigorously. 相似文献
185.
Xiujuan Wu Victoria S. Conlin Vijay Morampudi Natasha R. Ryz Yasmin Nasser Ganive Bhinder Kirk S. Bergstrom Hong B. Yu Chris C. M. Waterhouse Allison M. J. Buchan Oana E. Popescu William T. Gibson James A. Waschek Bruce A. Vallance Kevan Jacobson 《PloS one》2015,10(5)
Inflammatory bowel disease is a chronic gastrointestinal inflammatory disorder associated with changes in neuropeptide expression and function, including vasoactive intestinal peptide (VIP). VIP regulates intestinal vasomotor and secretomotor function and motility; however, VIP’s role in development and maintenance of colonic epithelial barrier homeostasis is unclear. Using VIP deficient (VIPKO) mice, we investigated VIP’s role in epithelial barrier homeostasis, and susceptibility to colitis. Colonic crypt morphology and epithelial barrier homeostasis were assessed in wildtype (WT) and VIPKO mice, at baseline. Colitic responses were evaluated following dinitrobenzene sulfonic acid (DNBS) or dextran-sodium sulfate (DSS) exposure. Mice were also treated with exogenous VIP. At baseline, VIPKO mice exhibited distorted colonic crypts, defects in epithelial cell proliferation and migration, increased apoptosis, and altered permeability. VIPKO mice also displayed reduced goblet cell numbers, and reduced expression of secreted goblet cell factors mucin 2 and trefoil factor 3. These changes were associated with reduced expression of caudal type homeobox 2 (Cdx2), a master regulator of intestinal function and homeostasis. DNBS and DSS-induced colitis were more severe in VIPKO than WT mice. VIP treatment rescued the phenotype, protecting VIPKO mice against DSS colitis, with results comparable to WT mice. In conclusion, VIP plays a crucial role in the development and maintenance of colonic epithelial barrier integrity under physiological conditions and promotes epithelial repair and homeostasis during colitis. 相似文献
186.
Peiyuan He Yuejin Yang Shubin Qiao Bo Xu Min Yao Yongjian Wu Jinqing Yuan Jue Chen Haibo Liu Jun Dai Xiao Yang Xinran Tang Yang Wang Wei Li Runlin Gao 《PloS one》2015,10(3)
Background
Transradial approach (TRA) outweighed transfemoral approach (TFA) in acute coronary syndrome patients because the former has better short-term outcomes in high-volume percutaneous coronary intervention (PCI) centers. Our study was one of the limited studies specifically in comparing the short- and medium-term effects of TRA and those of TFA in patients undergoing elective PCIs.Methods
A total of 21,242 patients who underwent elective PCI with stent implantation were included. Using propensity score methodology, 1,634 patient pairs were matched. Major clinical outcomes and PCI-related complications between TRA and TFA were compared.Results
In the propensity score-matched patients, the rates of in-hospital net adverse clinical events, which included death, myocardial infarction (MI), target vessel revascularization (TVR), stroke, and major bleeding, were much lower with TRA than with TFA (1.8% vs. 3.9%, P < 0.001). This difference was mainly due to the lower rate of major bleeding (0.6% vs. 1.8%, P < 0.001) and the decreased rate of MI (1.1% vs. 1.9%, P = 0.060). PCI-related dissection and thrombosis were similar between the TRA and TFA groups (both P > 0.05). Meanwhile, one-year incidence rates of major adverse cardiovascular events, which included death, MI, and TVR, were also similar (4.1% vs. 4.9%, P = 0.272) in TRA and TFA. Multivariable regression analyses showed that TRA was an independent predictor of the low rate of in-hospital net adverse clinical events (odds ratio, 0.53; 95% confidence interval, 0.40 to 0.71), but not of major adverse cardiovascular events at one-year follow-up (hazard ratio, 1.01; 95% confidence interval, 0.96 to 1.06).Conclusions
In patients undergoing elective PCI, TRA patients had lower rates of in-hospital net adverse clinical outcomes compared with TFA patients. TRA might be recommended as a routine approach in high-volume PCI hospitals for elective PCIs. 相似文献187.
Jiongming Sui Ya Wang Peng Wang Lixian Qiao Shimeng Sun Xiaohui Hu Jing Chen Jingshan Wang 《PloS one》2015,10(3)
In order to enlarge the potential resources of drought-tolerant peanuts, we conducted in vitro mutagenesis with Pingyangmycin (PYM) as the mutagen as well as directed screening on a medium supplemented with Hydroxyproline (HYP). After being extracted from mature seeds (cv. Huayu 20), the embryonic leaflets were cultured on somatic embryogenesis-induction medium with 4 mg/L PYM and the generated embryos were successively transferred to a germination medium with 4 and then 8 mmol/L HYP to screen HYP-tolerant plantlets. After that, these plantlets were grafted and transplanted to the experimental field. In the next generation, all seeds were sown in the field, and phenotype variation and trait segregation can be observed in most of the offspring (M2 generation). The M3 generation individuals were subjected to drought stress at the seedling stages. The activities of SOD and POD were substantially increased in eight offspring of 11 HYP-tolerant, regenerated plants than in their mutagenic parents. To determine the correlation between mutant phenotypes and genomic modification, we carried out a comparison of the DNA polymorphisms between the mutagenic parents and 13 M3 generation individuals from different HYP-tolerant, regenerated plants with SSR primers. Results showed that most mutants and parent plants had signs of polymorphisms. Under drought stress, some M3 generation individuals of 10 original HYP-tolerant, regenerated plants produced more pods than the mutagenic parent; twenty individuals among them produced >60 g pods/plant. M4-generation seeds were tested for quality characteristics by Near Infrared Spectroscopy (NIS) and nine individuals with higher protein content (>30%) and 21 individuals with higher oil content (>58%) were screened. We concluded that the use of PYM-based in vitro mutagenesis in combination with directed screening with HYP is effective for the creation of potential drought-tolerant mutants of peanut. 相似文献
188.
Aifen Zhou Kristina L Hillesland Zhili He Wendy Schackwitz Qichao Tu Grant M Zane Qiao Ma Yuanyuan Qu David A Stahl Judy D Wall Terry C Hazen Matthew W Fields Adam P Arkin Jizhong Zhou 《The ISME journal》2015,9(11):2360-2372
To investigate the genetic basis of microbial evolutionary adaptation to salt (NaCl) stress, populations of Desulfovibrio vulgaris Hildenborough (DvH), a sulfate-reducing bacterium important for the biogeochemical cycling of sulfur, carbon and nitrogen, and potentially the bioremediation of toxic heavy metals and radionuclides, were propagated under salt stress or non-stress conditions for 1200 generations. Whole-genome sequencing revealed 11 mutations in salt stress-evolved clone ES9-11 and 14 mutations in non-stress-evolved clone EC3-10. Whole-population sequencing data suggested the rapid selective sweep of the pre-existing polymorphisms under salt stress within the first 100 generations and the slow fixation of new mutations. Population genotyping data demonstrated that the rapid selective sweep of pre-existing polymorphisms was common in salt stress-evolved populations. In contrast, the selection of pre-existing polymorphisms was largely random in EC populations. Consistently, at 100 generations, stress-evolved population ES9 showed improved salt tolerance, namely increased growth rate (2.0-fold), higher biomass yield (1.8-fold) and shorter lag phase (0.7-fold) under higher salinity conditions. The beneficial nature of several mutations was confirmed by site-directed mutagenesis. All four tested mutations contributed to the shortened lag phases under higher salinity condition. In particular, compared with the salt tolerance improvement in ES9-11, a mutation in a histidine kinase protein gene lytS contributed 27% of the growth rate increase and 23% of the biomass yield increase while a mutation in hypothetical gene DVU2472 contributed 24% of the biomass yield increase. Our results suggested that a few beneficial mutations could lead to dramatic improvements in salt tolerance. 相似文献
189.
Beta‐diversity metrics of the upper digestive tract microbiome are associated with body mass index
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190.