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41.
The knowledge of rheological behaviour of juices and fruit derivatives is very useful both in the prediction of their stability
and in process design, and it depends on the type of juice and on the raw material with which they are produced. Most of the
equations that have been used to quantify flow behaviour describe the evolution of shear stress with the change of shear rate.
Nevertheless, the essential variable in equipment design is viscosity. In this way, a mathematical model to easily describe
the evolution of apparent viscosity of these non-Newtonian fluids with the shear rate would be very useful. In this work,
a mathematical expression has been developed, fitted to experimental data and compared with the Herschel–Bulkley one. The
obtained parameters with concentrated orange juice followed these trends: equilibrium apparent viscosity (η
∞) scarcely changed with temperature. Static apparent viscosity (η
0) decreased with increasing temperature, contrary to what happened with the flow behaviour constant k. 相似文献
42.
Pérez-Perarnau A Coll-Mulet L Rubio-Pati?o C Iglesias-Serret D Cosialls AM González-Gironès DM de Frias M de Sevilla AF de la Banda E Pons G Gil J 《Epigenetics》2011,6(10):1228-1235
Histone deacetylases (HDACs) play a key role in the regulation of acetylation status not only of histones but also of many other non-histone proteins involved in cell cycle regulation, differentiation or apoptosis. Therefore, histone deacetylase inhibitors (HDACi) have emerged as promising anticancer agents. Herein, we report the characterization of apoptosis in B-cell chronic lymphocytic leukemia (CLL) induced by two HDACi, Kendine 92 and SAHA. Both inhibitors induce dose-, time- and caspase-dependent apoptosis through the mitochondrial pathway. Interestingly, Kendine 92 and SAHA show a selective cytotoxicity for B lymphocytes and induce apoptosis in CLL cells with mutated or deleted TP53 as effectively as in tumor cells harboring wild-type TP53. The pattern of apoptosis-related gene and protein expression profile has been characterized. It has shown to be irrespective of TP53 status and highly similar between SAHA and Kendine 92 exposure. The balance between the increased BAD, BNIP3L, BNIP3, BIM, PUMA and AIF mRNA expression levels, and decreased expression of BCL-W, BCL-2, BFL-1, XIAP and FLIP indicates global changes in the apoptosis mRNA expression profile consistent with the apoptotic outcome. Protein expression analysis shows increased levels of NOXA, BIM and PUMA proteins upon Kendine 92 and SAHA treatment. Our results highlight the capability of these molecules to induce apoptosis not only in a selective manner but also in those cells frequently resistant to standard treatments. Thus, Kendine 92 is a novel HDACi with anticancer efficacy for non-proliferating CLL cells. 相似文献
43.
44.
Cadmium is an omnipotent environmental contaminant associated with the development of breast cancer. Studies suggest that cadmium functions as an endocrine disruptor, mimicking the actions of estrogen in breast cancer cells and activating the receptor to promote cell growth. Although acute cadmium exposure is known to promote estrogen receptor-mediated gene expression associated with growth, the consequence of chronic cadmium exposure is unclear. Since heavy metals are known to bioaccumulate, it is necessary to understand the effects of prolonged cadmium exposure. This study aims to investigate the effects of chronic cadmium exposure on breast cancer progression. A MCF7 breast cancer cell line chronically exposed to 10−7 M CdCl2 serves as our model system. Data suggest that prolonged cadmium exposures result in the development of more aggressive cancer phenotypes – increased cell growth, migration and invasion. The results from this study show for the first time that chronic cadmium exposure stimulates the expression of SDF-1 by altering the molecular interactions between ERα, c-jun and c-fos. This study provides a mechanistic link between chronic cadmium exposure and ERα and demonstrates that prolonged, low-level cadmium exposure contributes to breast cancer progression. 相似文献
45.
Herrera A Panisello JJ Ibarz E Cegoñino J Puértolas JA Gracia L 《Journal of biomechanics》2007,40(16):3615-3625
A hip replacement with a cemented or cementless femoral stem produces an effect on the bone called adaptive remodelling, attributable to mechanical and biological factors. The objective of all of cementless prostheses designs has been to achieve a perfect transfer of loads in order to avoid stress-shielding, which produces an osteopenia. In order to quantify this, the long term and mass-produced study with dual energy X-ray absorptiometry (DEXA) is necessary. Finite element (FE) simulation makes possible the explanation of the biomechanical changes which are produced in the femur after stem implantation. The good correlation obtained between the results of the FE simulation and the densitometric study allow, on one hand, to explain from the point of view of biomechanical performance the changes observed in bone density in the long-term, where it is clear that these are due to a different transfer of load in the implanted model compared to the healthy femur; on the other hand, it validates the simulation model, in a way that it can be used in different conditions and at different time periods, to carry out a sufficiently precise prediction of the evolution of the bone density from the biomechanical behaviour in the interaction between the prosthesis and femur. 相似文献
46.
Shuo Liu Simone Hausmann Scott Moore Carlson Mary Esmeralda Fuentes Joel William Francis Renjitha Pillai Shane Michael Lofgren Laura Hulea Kristofferson Tandoc Jiuwei Lu Ami Li Nicholas Dang Nguyen Marcello Caporicci Michael Paul Kim Anirban Maitra Huamin Wang Ignacio Ivan Wistuba John Anthony Porco Or Gozani 《Cell》2019,176(3):491-504.e21
47.
Alexandra Faulds‐Pain Susan M. Twine Evgeny Vinogradov Philippa C. R. Strong Anne Dell Anthony M. Buckley Gillian R. Douce Esmeralda Valiente Susan M. Logan Brendan W. Wren 《Molecular microbiology》2014,94(2):272-289
Clostridium difficile is a prominent nosocomial pathogen, proliferating and causing enteric disease in individuals with a compromised gut microflora. We characterized the post‐translational modification of flagellin in C. difficile 630. The structure of the modification was solved by nuclear magnetic resonance and shown to contain an N‐acetylglucosamine substituted with a phosphorylated N‐methyl‐l ‐threonine. A reverse genetics approach investigated the function of the putative four‐gene modification locus. All mutants were found to have truncated glycan structures by LC‐MS/MS, taking into account bioinformatic analysis, we propose that the open reading frame CD0241 encodes a kinase involved in the transfer of the phosphate to the threonine, the CD0242 protein catalyses the addition of the phosphothreonine to the N‐acetylglucosamine moiety and CD0243 transfers the methyl group to the threonine. Some mutations affected motility and caused cells to aggregate to each other and abiotic surfaces. Altering the structure of the flagellin modification impacted on colonization and disease recurrence in a murine model of infection, showing that alterations in the surface architecture of C. difficile vegetative cells can play a significant role in disease. We show that motility is not a requirement for colonization, but that colonization was compromised when the glycan structure was incomplete. 相似文献
48.
María Teruel Carmen P Simeon Jasper Broen Madelon C Vonk Patricia Carreira Maria Teresa Camps Rosa García-Portales Esmeralda Delgado-Frías Maria Gallego Gerard Espinosa the Spanish Scleroderma Group Lorenzo Beretta Paolo Airó Claudio Lunardi Gabriela Riemekasten Torsten Witte Thomas Krieg Alexander Kreuter J?rg HW Distler Nicolas Hunzelmann Bobby P Koeleman Alexandre E Voskuyl Annemie J Schuerwegh Miguel ángel González-Gay Timothy RDJ Radstake Javier Martin 《Arthritis research & therapy》2012,14(3):R154-6
Introduction
The aim of the present study was to investigate the possible role of CD40 and CD40 ligand (CD40LG) genes in the susceptibility and phenotype expression of systemic sclerosis (SSc).Methods
In total, 2,670 SSc patients and 3,245 healthy individuals from four European populations (Spain, Germany, The Netherlands, and Italy) were included in the study. Five single-nucleotide polymorphisms (SNPs) of CD40 (rs1883832, rs4810485, rs1535045) and CD40LG (rs3092952, rs3092920) were genotyped by using a predesigned TaqMan allele-discrimination assay technology. Meta-analysis was assessed to determine whether an association exists between the genetic variants and SSc or its main clinical subtypes.Results
No evidence of association between CD40 and CD40LG genes variants and susceptibility to SSc was observed. Similarly, no significant statistical differences were observed when SSc patients were stratified by the clinical subtypes, the serologic features, and pulmonary fibrosis.Conclusions
Our results do not suggest an important role of CD40 and CD40LG gene polymorphisms in the susceptibility to or clinical expression of SSc. 相似文献49.
Borja Belda-Palazón Leticia Ruiz Esmeralda Martí Susana Tárraga Antonio F. Tiburcio Francisco Culiá?ez Rosa Farràs Pedro Carrasco Alejandro Ferrando 《PloS one》2012,7(10)
Plant aminopropyltransferases consist of a group of enzymes that transfer aminopropyl groups derived from decarboxylated S-adenosyl-methionine (dcAdoMet or dcSAM) to propylamine acceptors to produce polyamines, ubiquitous metabolites with positive charge at physiological pH. Spermidine synthase (SPDS) uses putrescine as amino acceptor to form spermidine, whereas spermine synthase (SPMS) and thermospermine synthase (TSPMS) use spermidine as acceptor to synthesize the isomers spermine and thermospermine respectively. In previous work it was shown that both SPDS1 and SPDS2 can physically interact with SPMS although no data concerning the subcellular localization was reported. Here we study the subcellular localization of these enzymes and their protein dimer complexes with gateway-based Bimolecular Fluorescence Complementation (BiFC) binary vectors. In addition, we have characterized the molecular weight of the enzyme complexes by gel filtration chromatography with in vitro assembled recombinant enzymes and with endogenous plant protein extracts. Our data suggest that aminopropyltransferases display a dual subcellular localization both in the cytosol and nuclear enriched fractions, and they assemble preferably as dimers. The BiFC transient expression data suggest that aminopropyltransferase heterodimer complexes take place preferentially inside the nucleus. 相似文献
50.
Sanchez-Niño MD Bozic M Córdoba-Lanús E Valcheva P Gracia O Ibarz M Fernandez E Navarro-Gonzalez JF Ortiz A Valdivielso JM 《American journal of physiology. Renal physiology》2012,302(6):F647-F657
Local inflammation is thought to contribute to the progression of diabetic nephropathy. The vitamin D receptor (VDR) activator paricalcitol has an antiproteinuric effect in human diabetic nephropathy at high doses. We have explored potential anti-inflammatory effects of VDR activator doses that do not modulate proteinuria in an experimental model of diabetic nephropathy to gain insights into potential benefits of VDR activators in those patients whose proteinuria is not decreased by this therapy. The effect of calcitriol and paricalcitol on renal function, albuminuria, and renal inflammation was explored in a rat experimental model of diabetes induced by streptozotocin. Modulation of the expression of mediators of inflammation by these drugs was explored in cultured podocytes. At the doses used, neither calcitriol nor paricalcitol significantly modified renal function or reduced albuminuria in experimental diabetes. However, both drugs reduced the total kidney mRNA expression of IL-6, monocyte chemoattractant protein (MCP)-1, and IL-18. Immunohistochemistry showed that calcitriol and paricalcitol reduced MCP-1 and IL-6 in podocytes and tubular cells as well as glomerular infiltration by macrophages, glomerular cell NF-κB activation, apoptosis, and extracellular matrix deposition. In cultured podocytes, paricalcitol and calcitriol at concentrations in the physiological and clinically significant range prevented the increase in MCP-1, IL-6, renin, and fibronectin mRNA expression and the secretion of MCP-1 to the culture media induced by high glucose. In conclusion, in experimental diabetic nephropathy VDR activation has local renal anti-inflammatory effects that can be observed even when proteinuria is not decreased. This may be ascribed to decreased inflammatory responses of intrinsic renal cells, including podocytes, to high glucose. 相似文献