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991.
Laura Lucarini Lucia Magnelli Nicola Schiavone Alfonso Crisci Alessio Innocenti Luca Puccetti 《Journal of enzyme inhibition and medicinal chemistry》2018,33(1):234-240
Carbonic anhydrase (CA, EC 4.2.1.1) IX is regarded as a tumour hypoxia marker and CA inhibitors have been proposed as a new class of antitumor agents, with one such agent in Phase II clinical trials. The expression of some CAs, in particular the isoforms CA IX and CA XII, has been correlated with tumour aggressiveness and progression in several cancers. The aim of this study was to evaluate the possibility that CA IX could represent a marker related to clear cell Renal Cell Carcinoma (ccRCC). Bcl-2 and Bax, and the activity of caspase-3, evaluated in tissue biopsies from patients, were congruent with resistance to apoptosis in ccRCCs with respect to healthy controls, respectively. In the same samples, the CA IX and pro-angiogenic factor VEGF expressions revealed that both these hypoxia responsive proteins were strongly increased in ccRCC with respect to controls. CA IX plasma concentration and CA activity were assessed in healthy volunteers and patients with benign kidney tumours and ccRCCs. CA IX expression levels were found strongly increased only in plasma from ccRCC subjects, whereas, CA activity was found similarly increased both in plasma from ccRCC and benign tumour patients, compared to healthy volunteers. These results show that the plasmatic level of CA IX, but not the CA total activity, can be considered a diagnostic marker of ccRCCs. Furthermore, as many reports exist relating CA IX inhibition to a better outcome to anticancer therapy in ccRCC, plasma levels of CA IX could be also predictive for response to therapy. 相似文献
992.
Chenglin Zhu Vanessa Faillace Fulvio Laus Marilena Bazzano Luca Laghi 《Metabolomics : Official journal of the Metabolomic Society》2018,14(8):106
Background
Metabolomics has been recognized as a powerful approach for disease screening. In order to highlight potential health issues in subjects, a key factor is the possibility to compare quantitatively the metabolome of their biofluids with reference values from healthy individuals. Such efforts towards the systematic characterization of the metabolome of biofluids in perfect health conditions, far from concluded for humans, have barely begun on horses.Objectives
The present work attempts, for the first time, to give reference quantitative values for the molecules mostly represented in the urine metabolome of horses at rest and under light training, as observable by 1H-NMR.Methods
The metabolome of ten trotter horses, four male and six female, ranging from 3 to 8 years of age, has been observed by 1H-NMR spectroscopy before and after three training sessions.Results
We could characterize and quantify 54 molecules in trotter horse urine, originated from diet, protein digestion, energy generation or gut-microbial co-metabolism.Conclusion
We were able to describe how gender, age and exercise affected their concentration, by means of a two steps protocol based on univariate and robust principal component analysis.993.
994.
Assessing uncertainties in crop and pasture ensemble model simulations of productivity and N2O emissions 下载免费PDF全文
Fiona Ehrhardt Jean‐François Soussana Gianni Bellocchi Peter Grace Russel McAuliffe Sylvie Recous Renáta Sándor Pete Smith Val Snow Massimiliano de Antoni Migliorati Bruno Basso Arti Bhatia Lorenzo Brilli Jordi Doltra Christopher D. Dorich Luca Doro Nuala Fitton Sandro J. Giacomini Brian Grant Matthew T. Harrison Stephanie K. Jones Miko U. F. Kirschbaum Katja Klumpp Patricia Laville Joël Léonard Mark Liebig Mark Lieffering Raphaël Martin Raia S. Massad Elizabeth Meier Lutz Merbold Andrew D. Moore Vasileios Myrgiotis Paul Newton Elizabeth Pattey Susanne Rolinski Joanna Sharp Ward N. Smith Lianhai Wu Qing Zhang 《Global Change Biology》2018,24(2):e603-e616
Simulation models are extensively used to predict agricultural productivity and greenhouse gas emissions. However, the uncertainties of (reduced) model ensemble simulations have not been assessed systematically for variables affecting food security and climate change mitigation, within multi‐species agricultural contexts. We report an international model comparison and benchmarking exercise, showing the potential of multi‐model ensembles to predict productivity and nitrous oxide (N2O) emissions for wheat, maize, rice and temperate grasslands. Using a multi‐stage modelling protocol, from blind simulations (stage 1) to partial (stages 2–4) and full calibration (stage 5), 24 process‐based biogeochemical models were assessed individually or as an ensemble against long‐term experimental data from four temperate grassland and five arable crop rotation sites spanning four continents. Comparisons were performed by reference to the experimental uncertainties of observed yields and N2O emissions. Results showed that across sites and crop/grassland types, 23%–40% of the uncalibrated individual models were within two standard deviations (SD) of observed yields, while 42 (rice) to 96% (grasslands) of the models were within 1 SD of observed N2O emissions. At stage 1, ensembles formed by the three lowest prediction model errors predicted both yields and N2O emissions within experimental uncertainties for 44% and 33% of the crop and grassland growth cycles, respectively. Partial model calibration (stages 2–4) markedly reduced prediction errors of the full model ensemble E‐median for crop grain yields (from 36% at stage 1 down to 4% on average) and grassland productivity (from 44% to 27%) and to a lesser and more variable extent for N2O emissions. Yield‐scaled N2O emissions (N2O emissions divided by crop yields) were ranked accurately by three‐model ensembles across crop species and field sites. The potential of using process‐based model ensembles to predict jointly productivity and N2O emissions at field scale is discussed. 相似文献
995.
Gema Trigos‐Peral Luca P. Casacci Piotr ŚlipiŃski Irena M. GrzeŚ Dawid MoroŃ Hanna Babik Magdalena Witek 《Entomological Science》2018,21(3):270-278
The invasion of Solidago is one of the main threats to the biodiversity of natural meadows, leading to changes in animal and plant communities, as well as soil features. We compared effects of soil microclimatic conditions (temperature and moisture) and the availability of potential protein sources (dry mass of epigean invertebrates) on ants between meadows invaded by Solidago altissima and S. canadensis and those uninvaded. Our results showed that the ant communities were different between the uninvaded and invaded meadows, with reduction of ant abundance and species richness in the latter. Myrmica spp. were abundant in the uninvaded meadows, whereas Lasius niger was the dominant species in the invaded ones. We found that the lower moisture negatively influenced the abundance of Myrmica species in the Solidago‐invaded meadows. Moreover, the epigean invertebrate dry mass, as an estimation of the availability of protein sources, varied between the two types of meadows, with a higher abundance in the uninvaded ones. The abundance of Myrmica ants with narrower ecological requirements showed a positive correlation with the invertebrate biomass in the invaded meadows. In contrast, the abundance of L. niger with broad ecological requirements was negatively correlated with the invertebrate biomass in the invaded meadows, possibly as a strategy to reduce interspecific competition. Our study showed that the invasion of Solidago plants caused changes in the abundance and species composition of ant communities through modification in microhabitat conditions, that is, decreasing soil moisture, reducing biomass and changing distribution of prey invertebrates. 相似文献
996.
Quantitative mass spectrometry enables to monitor the abundance of thousands of proteins across biological conditions. Currently, most data analysis approaches rely on the assumption that the majority of the observed proteins remain unchanged across compared samples. Thus, gross morphological differences between cell states, deriving from, e.g., differences in size or number of organelles, are often not taken into account. Here, we analyzed multiple published datasets and frequently observed that proteins associated with a particular cellular compartment collectively increase or decrease in their abundance between conditions tested. We show that such effects, arising from underlying morphological differences, can skew the outcome of differential expression analysis. We propose a method to detect and normalize morphological effects underlying proteomics data. We demonstrate the applicability of our method to different datasets and biological questions including the analysis of sub‐cellular proteomes in the context of Caenorhabditis elegans aging. Our method provides a complementary perspective to classical differential expression analysis and enables to uncouple overall abundance changes from stoichiometric variations within defined group of proteins. 相似文献
997.
Raffaella Belvedere Valentina Bizzarro Luca Parente Francesco Petrella 《Cell Adhesion & Migration》2018,12(2):168-183
Prisma® Skin is a new pharmaceutical device developed by Mediolanum Farmaceutici S.p.a. It includes alginates, hyaluronic acid and mainly mesoglycan. The latter is a natural glycosaminoglycan preparation containing chondroitin sulfate, dermatan sulfate, heparan sulfate and heparin and it is used in the treatment of vascular disease. Glycosaminoglycans may contribute to the re-epithelialization in the skin wound healing, as components of the extracellular matrix. Here we describe, for the first time, the effects of Prisma® Skin in in vitro cultures of adult epidermal keratinocytes and dermal fibroblasts. Once confirmed the lack of cytotoxicity by mesoglycan and Prisma® Skin, we have shown the increase of S and G2 phases of fibroblasts cell cycle distribution. We further report the strong induction of cell migration rate and invasion capability on both cell lines, two key processes of wound repair. In support of these results, we found significant cytoskeletal reorganization, following the treatments with mesoglycan and Prisma® Skin, as confirmed by the formation of F-actin stress fibers. Additionally, together with a significant reduction of E-cadherin, keratinocytes showed an increase of CD44 expression and the translocation of ezrin to the plasma membrane, suggesting the involvement of CD44/ERM (ezrin-radixin-moesin) pathway in the induction of the analyzed processes. Furthermore, as showed by immunofluorescence assay, fibroblasts treated with mesoglycan and Prisma® Skin exhibited the increase of Fibroblast Activated Protein α and a remarkable change in shape and orientation, two common features of reactive stromal fibroblasts. In all experiments Prisma® Skin was slightly more potent than mesoglycan. In conclusion, based on these findings we suggest that Prisma® Skin may be able to accelerate the healing process in venous skin ulcers, principally enhancing re-epithelialization and granulation processes. 相似文献
998.
Targeting the phosphatidylinositol 3‐kinase/Akt/mechanistic target of rapamycin signaling pathway in B‐lineage acute lymphoblastic leukemia: An update 下载免费PDF全文
999.
Decellularized colorectal cancer matrix as bioactive microenvironment for in vitro 3D cancer research 下载免费PDF全文
1000.
Salinee Jantrapirom Luca Lo Piccolo Hideki Yoshida Masamitsu Yamaguchi 《Experimental cell research》2018,362(2):461-471
Ubiquilin (UBQLN) plays a crucial role in cellular proteostasis through its involvement in the ubiquitin proteasome system and autophagy. Mutations in the UBQLN2 gene have been implicated in amyotrophic lateral sclerosis (ALS) and ALS with frontotemporal lobar dementia (ALS/FTLD). Previous studies reported a key role for UBQLN in Alzheimer's disease (AD); however, the mechanistic involvement of UBQLN in other neurodegenerative diseases remains unclear. The genome of Drosophila contains a single UBQLN homolog (dUbqn) that shows high similarity to UBQLN1 and UBQLN2; therefore, the fly is a useful model for characterizing the role of UBQLN in vivo in neurological disorders affecting locomotion and learning abilities. We herein performed a phenotypic and molecular characterization of diverse dUbqn RNAi lines. We found that the depletion of dUbqn induced the accumulation of polyubiquitinated proteins and caused morphological defects in various tissues. Our results showed that structural defects in larval neuromuscular junctions, abdominal neuromeres, and mushroom bodies correlated with limited abilities in locomotion, learning, and memory. These results contribute to our understanding of the impact of impaired proteostasis in neurodegenerative diseases and provide a useful Drosophila model for the development of promising therapies for ALS and FTLD. 相似文献