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31.
Of the most important clinical needs for bladder cancer (BC) management is the identification of biomarkers for disease aggressiveness. Urine is a "gold mine" for biomarker discovery, nevertheless, with multiple proteins being in low amounts, urine proteomics becomes challenging. In the present study we applied a fractionation strategy of urinary proteins based on the use of immobilized metal affinity chromatography for the discovery of biomarkers for aggressive BC. Urine samples from patients with non invasive (two pools) and invasive (two pools) BC were subjected to immobilized metal affinity chromatography fractionation and eluted proteins analyzed by 1D-SDS-PAGE, band excision and liquid chromatography tandem MS. Among the identified proteins, multiple corresponded to proteins with affinity for metals and/or reported to be phosphorylated and included proteins with demonstrated association with BC such as MMP9, fibrinogen forms, and clusterin. In agreement to the immobilized metal affinity chromatography results, aminopeptidase N, profilin 1, and myeloblastin were further found to be differentially expressed in urine from patients with invasive compared with non invasive BC and benign controls, by Western blot or Elisa analysis, nevertheless exhibiting high interindividual variability. By tissue microarray analysis, profilin 1 was found to have a marked decrease of expression in the epithelial cells of the invasive (T2+) versus high risk non invasive (T1G3) tumors with occasional expression in stroma; importantly, this pattern strongly correlated with poor prognosis and increased mortality. The functional relevance of profilin 1 was investigated in the T24 BC cells where blockage of the protein by the use of antibodies resulted in decreased cell motility with concomitant decrease in actin polymerization. Collectively, our study involves the application of a fractionation method of urinary proteins and as one main result of this analysis reveals the association of profilin 1 with BC paving the way for its further investigation in BC stratification.  相似文献   
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Research has shown that children usually provide teleological explanations for the features of organisms and artifacts, from a very early age (3–4 years old). However, there is no consensus on whether teleological explanations are given in the same manner for non-living natural objects as well. The present study aimed to document the teleological explanations of 5- to 8-year-old children for particular features (color and shape) of organisms, artifacts and non-living natural objects. In addition, it was examined if there was any correlation between these explanations and children’s explanations for the usefulness of those features. Our results indicate a developmental shift in children’s teleological explanations, from a non-selective teleology in pre-school to a selective one in the second grade. In the latter case, children provided teleological explanations mostly for the shape of the feet of organisms and for the shape of artifacts, whereas pre-school children provided teleological explanations for non-living natural objects as well, both for the color and for the shape in all cases. Our results are not conclusive and further research is required, including a larger spectrum of students, since teleology is one of the most important conceptual obstacles in understanding evolution that persists even into adulthood. We conclude by proposing a particular research program for this purpose.  相似文献   
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Pathological features of chronic obstructive pulmonary disease (COPD) include lung vascular remodeling and angiogenesis. Angiopoietin-1 (Ang-1), is an essential mediator of angiogenesis by establishing vascular integrity, whereas angiopoietin-2 (Ang-2) acts as its natural inhibitor. We determined the levels of angiopoietins in sputum supernatants of patients with COPD and investigated their possible association with mediators and cells involved in the inflammatory and remodeling process. Fifty-nine patients with COPD, 25 healthy smokers and 20 healthy non-smokers were studied. All subjects underwent lung function tests, sputum induction for cell count identification and Ang-1, Ang-2, VEGF, TGF-β1, MMP-2, LTB4, IL-8, albumin measurement in sputum supernatants. Airway vascular permeability (AVP) index was also assessed. Ang-2 levels were significantly higher in patients with COPD compared to healthy smokers and healthy non-smokers [median, interquartile ranges pg/ml, 267 (147-367) vs. 112 (67-171) and 98 (95-107), respectively; p<0.001]. Regression analysis showed a significant association between Ang-2 levels and AVP index, VEGF, IL-8 and MMP-2 levels in COPD, the strongest being with VEGF. Our results indicate that induced sputum Ang-2 levels are higher in COPD compared to healthy smokers and healthy non-smokers. Moreover, Ang-2 is associated with AVP, IL-8, MMP-2, and VEGF, indicating a possible role for Ang-2 in the pathogenesis of the disease.  相似文献   
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Aim A large body of knowledge exists on individual anthropogenic threats that have an impact on marine biodiversity in the Mediterranean Sea, although we know little about how these threats accumulate and interact to affect marine species and ecosystems. In this context, we aimed to identify the main areas where the interaction between marine biodiversity and threats is more pronounced and to assess their spatial overlap with current marine protected areas in the Mediterranean. Location Mediterranean Sea. Methods We first identified areas of high biodiversity of marine mammals, marine turtles, seabirds, fishes and commercial or well‐documented invertebrates. We mapped potential areas of high threat where multiple threats are occurring simultaneously. Finally we quantified the areas of conservation concern for biodiversity by looking at the spatial overlap between high biodiversity and high cumulative threats, and we assessed the overlap with protected areas. Results Our results show that areas with high marine biodiversity in the Mediterranean Sea are mainly located along the central and north shores, with lower values in the south‐eastern regions. Areas of potential high cumulative threats are widespread in both the western and eastern basins, with fewer areas located in the south‐eastern region. The interaction between areas of high biodiversity and threats for invertebrates, fishes and large animals in general (including large fishes, marine mammals, marine turtles and seabirds) is concentrated in the coastal areas of Spain, Gulf of Lions, north‐eastern Ligurian Sea, Adriatic Sea, Aegean Sea, south‐eastern Turkey and regions surrounding the Nile Delta and north‐west African coasts. Areas of concern are larger for marine mammal and seabird species. Main conclusions These areas may represent good candidates for further research, management and protection activities, since there is only a maximum 2% overlap between existing marine protected areas (which cover 5% of the Mediterranean Sea) and our predicted areas of conservation concern for biodiversity.  相似文献   
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Background

The thermophilic anaerobe Thermoanaerobacterium saccharolyticum is capable of directly fermenting xylan and the biomass-derived sugars glucose, cellobiose, xylose, mannose, galactose and arabinose. It has been metabolically engineered and developed as a biocatalyst for the production of ethanol.

Results

We report the initial characterization of the carbon catabolite repression system in this organism. We find that sugar metabolism in T. saccharolyticum is regulated by histidine-containing protein HPr. We describe a mutation in HPr, His15Asp, that leads to derepression of less-favored carbon source utilization.

Conclusion

Co-utilization of sugars can be achieved by mutation of HPr in T. saccharolyticum. Further manipulation of CCR in this organism will be instrumental in achieving complete and rapid conversion of all available sugars to ethanol.
  相似文献   
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Background

Tumor microenvironment consists of the extracellular matrix (ECM), stromal cells, such as fibroblasts (FBs) and cancer associated fibroblasts (CAFs), and a myriad of soluble factors. In many tumor types, including pancreatic tumors, the interplay between stromal cells and the other tumor microenvironment components leads to desmoplasia, a cancer-specific type of fibrosis that hinders treatment. Transforming growth factor beta (TGF-β) and CAFs are thought to play a crucial role in this tumor desmoplastic reaction, although the involved mechanisms are unknown.

Methods

Optical/fluorescence microscopy, atomic force microscopy, image processing techniques, invasion assay in 3D collagen I gels and real-time PCR were employed to investigate the effect of TGF-β on normal pancreatic FBs and CAFs with regard to crucial cellular morphodynamic characteristics and relevant gene expression involved in tumor progression and metastasis.

Results

CAFs present specific myofibroblast-like characteristics, such as α-smooth muscle actin expression and cell elongation, they also form more lamellipodia and are softer than FBs. TGF-β treatment increases cell stiffness (Young's modulus) of both FBs and CAFs and increases CAF's (but not FB's) elongation, cell spreading, lamellipodia formation and spheroid invasion. Gene expression analysis shows that these morphodynamic characteristics are mediated by Rac, RhoA and ROCK expression in CAFs treated with TGF-β.

Conclusions

TGF-β modulates CAFs', but not FBs', cell shape, stiffness and invasion.

General Significance

Our findings elucidate on the effects of TGF-β on CAFs' behavior and stiffness providing new insights into the mechanisms involved.  相似文献   
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