635 research outputs found

    A Sox2–Sox9 signalling axis maintains human breast luminal progenitor and breast cancer stem cells

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    Increased cancer stem cell content during development of resistance to tamoxifen in breast cancer is driven by multiple signals, including Sox2-dependent activation of Wnt signalling. Here, we show that Sox2 increases and estrogen reduces the expression of the transcription factor Sox9. Gain and loss of function assays indicate that Sox9 is implicated in the maintenance of human breast luminal progenitor cells. CRISPR/Cas knockout of Sox9 reduces growth of tamoxifen-resistant breast tumours in vivo. Mechanistically, Sox9 acts downstream of Sox2 to control luminal progenitor cell content and is required for expression of the cancer stem cell marker ALDH1A3 and Wnt signalling activity. Sox9 is elevated in breast cancer patients after endocrine therapy failure. This new regulatory axis highlights the relevance of SOX family transcription factors as potential therapeutic targets in breast cancer

    Advances of hyaluronic acid in stem cell therapy and tissue engineering, including current clinical trials

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    yaluronic acid (HA), as one of the main components of the extracellular matrix (ECM), plays a significant role in a multitude of biological processes involving cell migration, proliferation, differentiation, wound healing and inflammation. Thanks to its excellent biocompatibility, biodegradability and hygroscopic properties, HA has been used in its natural form for joint lubrication and ocular treatment. The chemical structure of HA can be easily modified by direct reaction with its carboxyl and hydroxyl groups. Recently, HA derivatives have been synthesised with the aim of developing HA-based materials with increased mechanical strength, improved cell interactions and reduced biodegradation and studied for regenerative medicine purposes, including cell therapy and tissue engineering. In this context, the present manuscript reviews HA applications from a basic point of view – including chemical modifications and cellular biology aspects related to clinical translation – and future perspectives of using biofabrication technologies for regenerative medicine. A detailed description of current clinical trials, testing advanced therapies based on combination of stem cells and HA formulations, is included. The final goal was to offer an integral portrait and a deeper comprehension of the current applications of HA from bench to bedside

    Impaired Mitophagy and Protein Acetylation Levels in Fibroblasts from Parkinson's Disease Patients

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    Parkinson's disease (PD) is a chronic and progressive neurodegenerative disorder. While most PD cases are idiopathic, the known genetic causes of PD are useful to understand common disease mechanisms. Recent data suggests that autophagy is regulated by protein acetylation mediated by histone acetyltransferase (HAT) and histone deacetylase (HDAC) activities. The changes in histone acetylation reported to be involved in PD pathogenesis have prompted this investigation of protein acetylation and HAT and HDAC activities in both idiopathic PD and G2019S leucine-rich repeat kinase 2 (LRRK2) cell cultures. Fibroblasts from PD patients (with or without the G2019S LRRK2 mutation) and control subjects were used to assess the different phenotypes between idiopathic and genetic PD. G2019S LRRK2 mutation displays increased mitophagy due to the activation of class III HDACs whereas idiopathic PD exhibits downregulation of clearance of defective mitochondria. This reduction of mitophagy is accompanied by more reactive oxygen species (ROS). In parallel, the acetylation protein levels of idiopathic and genetic individuals are different due to an upregulation in class I and II HDACs. Despite this upregulation, the total HDAC activity is decreased in idiopathic PD and the total HAT activity does not significantly vary. Mitophagy upregulation is beneficial for reducing the ROS-induced harm in genetic PD. The defective mitophagy in idiopathic PD is inherent to the decrease in class III HDACs. Thus, there is an imbalance between total HATs and HDACs activities in idiopathic PD, which increases cell death. The inhibition of HATs in idiopathic PD cells displays a cytoprotective effect

    Enhancement of Water Transport and Microstructural Changes Induced by High-Intesity Ultrasound Application on Orange Peel Drying

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    The main aim of this work was to evaluate the effect of high-intensity ultrasound (US) on the drying kinetics of orange peel as well as its influence on the microstructural changes induced during drying. Convective drying kinetics of orange peel slabs were carried out at a relative humidity of 26.5±0.9%, 40 °C and 1 m/s with (AIR+US) and without (AIR) ultrasound application. In order to identify the US effect on water transport, drying kinetics were analyzed by taking the diffusion theory into account. Fresh, AIR and AIR+US dried samples were analyzed using Cryo-Scanning Electron Microscopy. Results showed that the drying kinetics of orange peel were significantly improved by US application, which involved a significant (p<0.05) improvement of mass transfer coefficient and effective moisture diffusivity. The effects on mass transfer properties were confirmed with microstructural observations. In the cuticle surface of flavedo, the pores were obstructed by the spread of the waxy components, this fact evidencing US effects on the air solid interfaces. Furthermore, the cells of the albedo were disrupted by US, as it created large intercellular air spaces facilitating water transfer through the tissue.The authors would like to acknowledge the financial support of MICINN and CEE (European Regional Development Fund) from projects Ref. DPI2009-14549-C04-04, PSE-060000-2009-003, and FP6-2004-FOOD-23140 HIGHQ RTE.GarcĂ­a PĂ©rez, JV.; Ortuño Cases, C.; Puig GĂłmez, CA.; CĂĄrcel CarriĂłn, JA.; PĂ©rez Munuera, IM. (2012). Enhancement of Water Transport and Microstructural Changes Induced by High-Intesity Ultrasound Application on Orange Peel Drying. Food and Bioprocess Technology. 5(6):2256-2265. https://doi.org/10.1007/s11947-011-0645-0S2256226556Alandes, L., Perez-Munuera, I., Llorca, E., Quiles, A., & Hernando, I. (2009). Use of calcium lactate to improve structure of “Flor de Invierno” fresh-cut pears. Postharvest Biology and Technology, 53(3), 145–151.Anagnostopoulou, M. A., Kefalas, P., Papageorgiou, V. P., Assimopoulou, A. N., & Boskou, D. (2006). Radical scavenging activity of various extracts and fractions of sweet orange peel (Citrus sinensis). Food Chemistry, 94(1), 19–25.AOAC. (1997). Official methods of analysis. Arlington: Association of Official Analytical Chemist.Arslan, D., Özcan, M. M. (2011). Evaluation of drying methods with respect to drying kinetics, mineral content, and color characteristics of savory leaves. Food and Bioprocess Technology. doi: 10.1007/s11947-010-0498-y , in press.CĂĄrcel, J. A., Garcia-Perez, J. V., Riera, E., & Mulet, A. (2007). Influence of high intensity ultrasound on drying kinetics of persimmon. Drying Technology, 25(1), 185–193.Chafer, M., Gonzalez-Martinez, C., Chiralt, A., & Fito, P. (2003). Microstructure and vacuum impregnation response of citrus peles. Food Research International, 36(1), 35–41.Chau, C., Sheu, F., Huang, Y., & Su, L. (2005). Improvement in intestinal function and health by the peel fibre derived from Citrus sinensis L cv Liucheng. Journal of the Science of Food & Agriculture, 85(7), 1211–1216.Crank J. (1975). The Mathematics of diffusion. Oxford (2nd ed.), UK: Clarendon Press.Cruz, R. M. S., Vieira, M. C., Fonseca, S. C., Silva, C. L. M. (2010). Impact of thermal blanching and thermosonication treatments on watercress (Nasturtium officinale) quality: thermosonication process optimization and microstructure evaluation. Food and Bioprocess Technology. doi: 10.1007/s11947-009-0220-0 , in press.Delgado, A. E., Zheng, L., & Sun, D.-W. (2010). Influence of ultrasound on freezing rate of immersion-frozen apples. Food and Bioprocess Technology, 2(3), 263–270.FAOSTAT (2010). FAO Statistical Databases. Food and Agriculture of the United Nations. Available at: http://faostat.fao.org/site/291/default.aspx . Accessed 15 January 2010.Fernandes, F. A. N., Gallao, M. I., & Rodrigues, S. (2008a). Effect of osmotic dehydration and ultrasound pre-treatment on cell structure: Melon dehydration. Food Science and Technology, 41(4), 604–610.Fernandes, F. A. N., Oliveira, F. I. P., & Rodrigues, S. (2008b). Use of ultrasound for dehydration of papayas. Food and Bioprocess Technology, 1(4), 339–345.Gabaldon-Leyva, C. A., Quintero-Ramos, A., Barnard, J., BalandrĂĄn-Quintana, R., TalamĂĄs-Abbud, R., & JimĂ©nez-Castro, J. (2007). Effect of ultrasound on the mass transfer and physical changes in brine bell pepper at different temperatures. Journal of Food Engineering, 81(2), 374–379.Gallego-JuĂĄrez, J. A. (1998). Some applications of air-borne power ultrasound to food processing. In M. J. W., Povey, T. J. Mason (Eds.), Ultrasound in Food Processing. UK: London, Chapman & Hall.Gallego-JuĂĄrez, J. A., RodrĂ­guez-Corral, G., GĂĄlvez-Moraleda, J. C., & Yang, T. S. (1999). A new high intensity ultrasonic technology for food dehydration. Drying Technology, 17(3), 597–608.Garau, M. C., Simal, S., Femenia, A., & RossellĂł, C. (2006). Drying of orange skin: drying kinetics modelling and functional properties. Journal of Food Engineering, 75(2), 288–295.Garau, M. C., Simal, S., Rossello, C., & Femenia, A. (2007). Effect of air-drying temperature on physico-chemical properties of dietary fibre and antioxidant capacity of orange (Citrus aurantium v. Canoneta) by-products. Food Chemistry, 104(3), 1014–1024.Garcia-Perez, J. V., CĂĄrcel, J. A., De la Fuente, S., & Riera, E. (2006). Ultrasonic drying of foodstuff in a fluidized bed. Parametric study. Ultrasonics, 44, 539–543.Garcia-Perez, J. V., CĂĄrcel, J. A., Benedito, J., & Mulet, A. (2007). Power ultrasound mass transfer enhancement in food drying. Food and Bioproducts Proccessing, 85(3), 247–254.GuinĂ©, R. P. F., Henrriques, F., Barroca, M. J. (2010). Mass transfer coefficients for the drying of pumpkin (Cucurbita moschata) and dried product quality. Food and Bioprocess Technology. doi: 10.1007/s11947-009-0275 , in press.Khalloufi, S., Almeida-Rivera, C., & Bongers, P. (2009). A theoretical model and its experimental validation to predict the porosity as a function of shrinkage and collapse phenomena during drying. Food Research International, 42(8), 1122–1130.Larrauri, J. A., RupĂ©rez, P., Bravo, L., & Saura-Calixto, F. (1996). High dietary fibre powders from orange and lime peels: associated polyphenols and antioxidant capacity. Food Research International, 29(8), 757–762.Mujumdar, A. S., & Law, C. L. (2010). Drying technology: trends and applications in postharvest processing. Food and Bioprocess Technology, 3(6), 843–852.Mulet, A., Blasco, M., GarcĂ­a-Reverter, J., & Garcia-Perez, J. V. (2005). Drying kinetics of Curcuma longa rhizomes. Journal of Food Science, 7(5), 318–323.Oliveira, F. I. P., Gallao, M. I., Rodrigues, S., Fernandes, F.A.N. (2010). Dehydration of malay apple (Syzygium malaccense L.) using ultrasound as a pretreatment. Food and Bioprocess Technology. doi: 10.1007/s11947-010-0351-3 , in press.Ortuño, C., Perez-Munuera, I., Puig, A., Riera, E., & Garcia-Perez, J.V. (2010). Influence of power ultrasound application on mass transport and microstructure of orange peel during hot air drying. Physics Procedia, 3, 153–159.Perry, R. H. & Chilton, C. H. (1973). Chemical Engineers’ Handbook. McGraw Hill (5th ed.), New York, US.Ruiz-LĂłpez, I. I., Castillo-Zamudio, R. I., Salgado-Cervantes, M. A., RodrĂ­guez-Jimenes, G. C., & GarcĂ­a-Alvarado, M. A. (2010). Mass transfer modelling during osmotic dehydration of hexahedral pineapple slices in limited volume solutions. Food and Bioprocess Technology, 3(3), 427–433.Salvador, A., Salvador, L., Besada, C., Larrea, V., Hernando, I., & Perez-Munuera, I. (2008). Reduced effectiveness of the treatment for removing astringency in persimmon fruit when stored at 15 °C: Physiological and microstructural study. Postharvest Biology and Technology, 49(3), 340–347.Sanchez, E. S., Simal, S., FemenĂ­a, A., Benedito, J., & RosellĂł, C. (2001). Effect of acoustic brining on lipolysis and on sensory characteristics of Mahon cheese. Journal of Food Science, 66(6), 892–896.Sanchez, E. S., Simal, S., FemenĂ­a, A., Llul, P., & RosellĂł, C. (2001). Proteolysis of Mahon cheese as affected by acoustic-assited brining. European Food Research and Technology, 212(2), 147–152.Sharma, A., & Gupta, M. N. (2006). Ultrasonic pre-irradiation effect upon aqueous enzymatic oil extraction from almond and apricot seeds. Ultrasonics Sonochemistry, 13(6), 529–534.Simal, S., Rosello, C., & Mulet, A. (1998). Modelling of air drying in regular shaped bodies. Trends in Chemical Engineering, 4(4), 171–180.Simal, S., Femenia, A., & Garcia-Pascual, P. (2003). Simulation of the drying curves of a meat-based product: effect of the external resistance to mass transfer. Journal of Food Engineering, 58(2), 193–199.Singh, R. P., & Heldman, D. R. (2001). Introduction to Food Engineering. Academic Press (3rd ed.): San Diego.Toma, M., Vinatoru, M., Paniwnyk, L., & Mason, T. J. (2001). Investigation of the effects of ultrasound on vegetal tissues during solvent extraction. Ultrasonics Sonochemistry, 8(2), 137–142

    Use of aspirin for primary and secondary prevention of cardiovascular disease in diabetic patients in an ambulatory care setting in Spain

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    <p>Abstract</p> <p>Background</p> <p>This study was conducted in order to determine the use of aspirin and to assess the achievement of therapeutic targets in diabetic patients according to primary (PP) or secondary prevention (SP).</p> <p>Methods</p> <p>This is a retrospective, observational study including patients ≄18 years with diabetes mellitus followed in four primary care centers. Measurements included demographics, use of aspirin and/or anticoagulant drugs, co-morbidities, clinical parameters and proportion of patient at therapeutic target (TT). Descriptive statistics, chi-square test and logistic regression model were used for significance.</p> <p>Results</p> <p>A total of 4,140 patients were analyzed, 79.1% (95% confidence intervals [CI]: 77.7–80.5%) in PP and 20.9% (95% CI: 18.2–23.7%) in SP. Mean age was 64.1 (13.8) years, and 49.3% of patient were men (PP: 46.3, SP: 60.7, p = 0.001). Aspirin was prescribed routinely in 20.8% (95% CI: 19.4–22.2%) in PP and 60.8% (95% CI: 57.6–64.0%) in SP. Proportion of patient at TT was 48.0% for blood pressure and 59.8% for cholesterol. Use of aspirin was associated to increased age [OR = 1.01 (95% CI: 1.00–1.02); p = 0.011], cardiovascular-risk factors [OR = 1.14 (95% CI: 1.03–1.27); p = 0.013], LDL-C [OR = 1.42 (95% CI: 1.06–1.88); p = 0.017] and higher glycated hemoglobin [OR = 1.51 (95% CI: 1.22–1.89); p = 0.000] were covariates associated to the use of aspirin in PP.</p> <p>Conclusion</p> <p>Treatment with aspirin is underused for PP in patients with diabetes mellitus in Primary Care. Achievement of TT should be improved.</p

    Preliminary molecular genetic analysis of the Receptor Interacting Protein 140 (RIP140) in women affected by endometriosis

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    BACKGROUND: Endometriosis is a complex disease affecting 10–15% of women at reproductive age. Very few genes are known to be altered in this pathology. RIP140 protein is an important cofactor of oestrogen receptor and many other nuclear receptors. Targeting disruption experiments of nrip1 gene in mice have demonstrated that nuclear receptor interacting protein 1 gene (nrip1), the gene encoding for rip140 protein, is essential for female fertility. Specifically, mice null for nrip1 gene are viable, but females are infertile because of complete failure of mature follicles to release oocytes at ovulation stage. The ovarian phenotype observed in mice devoid of rip140 closely resembles the luteinized unruptured follicle (LUF) syndrome that is observed in a high proportion of women affected of endometriosis or idiopathic infertility. Here we present a preliminary work that analyses the role of NRIP1 gene in humans. METHODS: We have sequenced the complete coding region of NRIP1 gene in 20 unrelated patients affected by endometriosis. We have performed genetic association studies by using the DNA variants identified during the sequencing process. RESULTS: We identified six DNA variants within the coding sequence of NRIP1 gene, and five of them generated amino acid changes in the protein. We observed that three of twenty sequenced patients have specific combinations of amino-acid variants within the RIP140 protein that are poorly represented in the control population (p = 0.006). Moreover, we found that Arg448Gly, a common polymorphism located within NRIP1 gene, is associated with endometriosis in a case-control study (59 cases and 141 controls, p(allele positivity test )= 0.027). CONCLUSION: Our results suggest that NRIP1 gene variants, separately or in combinations, might act as predisposing factors for human endometriosis

    Preferential Occupancy of R2 Retroelements on the B Chromosomes of the Grasshopper Eyprepocnemis plorans

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    R2 non-LTR retrotransposons exclusively insert into the 28S rRNA genes of their host, and are expressed by co-transcription with the rDNA unit. The grasshopper Eyprepocnemis plorans contains transcribed rDNA clusters on most of its A chromosomes, as well as non-transcribed rDNA clusters on the parasitic B chromosomes found in many populations. Here the structure of the E. plorans R2 element, its abundance relative to the number of rDNA units and its retrotransposition activity were determined. Animals screened from five populations contained on average over 12,000 rDNA units on their A chromosomes, but surprisingly only about 100 R2 elements. Monitoring the patterns of R2 insertions in individuals from these populations revealed only low levels of retrotransposition. The low rates of R2 insertion observed in E. plorans differ from the high levels of R2 insertion previously observed in insect species that have many fewer rDNA units. It is proposed that high levels of R2 are strongly selected against in E. plorans, because the rDNA transcription machinery in this species is unable to differentiate between R2-inserted and uninserted units. The B chromosomes of E. plorans contain an additional 7,000 to 15,000 rDNA units, but in contrast to the A chromosomes, from 150 to over 1,500 R2 elements. The higher concentration of R2 in the inactive B chromosomes rDNA clusters suggests these chromosomes can act as a sink for R2 insertions thus further reducing the level of insertions on the A chromosomes. These studies suggest an interesting evolutionary relationship between the parasitic B chromosomes and R2 elements.This study was supported by grants from the Spanish Ministerio de Ciencia y TecnologĂ­a (CGL2009-11917) and Plan Andaluz de Investigacion (CVI-6649), and was partially performed by FEDER funds and a grant from the National Institutes of Health (GM42790)

    Prospective associations between a priori dietary patterns adherence and kidney function in an elderly Mediterranean population at high cardiovascular risk.

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    PURPOSE: To assess the association between three different a priori dietary patterns adherence (17-item energy reduced-Mediterranean Diet (MedDiet), Trichopoulou-MedDiet and Dietary Approach to Stop Hypertension (DASH)), as well as the Protein Diet Score and kidney function decline after one year of follow-up in elderly individuals with overweight/obesity and metabolic syndrome (MetS). METHODS: We prospectively analyzed 5675 participants (55-75 years) from the PREDIMED-Plus study. At baseline and at one year, we evaluated the creatinine-based estimated glomerular filtration rate (eGFR) and food-frequency questionnaires-derived dietary scores. Associations between four categories (decrease/maintenance and tertiles of increase) of each dietary pattern and changes in eGFR (ml/min/1.73m2) or ≄ 10% eGFR decline were assessed by fitting multivariable linear or logistic regression models, as appropriate. RESULTS: Participants in the highest tertile of increase in 17-item erMedDiet Score showed higher upward changes in eGFR (ÎČ: 1.87 ml/min/1.73m2; 95% CI: 1.00-2.73) and had lower odds of ≄ 10% eGFR decline (OR: 0.62; 95% CI: 0.47-0.82) compared to individuals in the decrease/maintenance category, while Trichopoulou-MedDiet and DASH Scores were not associated with any renal outcomes. Those in the highest tertile of increase in Protein Diet Score had greater downward changes in eGFR (ÎČ: - 0.87 ml/min/1.73m2; 95% CI: - 1.73 to - 0.01) and 32% higher odds of eGFR decline (OR: 1.32; 95% CI: 1.00-1.75). CONCLUSIONS: Among elderly individuals with overweight/obesity and MetS, only higher upward change in the 17-item erMedDiet score adherence was associated with better kidney function after one year. However, increasing Protein Diet Score appeared to have an adverse impact on kidney health. TRIAL REGISTRATION NUMBER: ISRCTN89898870 (Data of registration: 2014)

    Model for the Peptide-Free Conformation of Class II MHC Proteins

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    Background: Major histocompatibility complex proteins are believed to undergo significant conformational changes concomitant with peptide binding, but structural characterization of these changes has remained elusive. Methodology/Principal Findings: Here we use molecular dynamics simulations and experimental probes of protein conformation to investigate the peptide-free state of class II MHC proteins. Upon computational removal of the bound peptide from HLA-DR1-peptide complex, the a50-59 region folded into the P1-P4 region of the peptide binding site, adopting the same conformation as a bound peptide. Strikingly, the structure of the hydrophobic P1 pocket is maintained by engagement of the side chain of Phe a54. In addition, conserved hydrogen bonds observed in crystal structures between the peptide backbone and numerous MHC side chains are maintained between the a51-55 region and the rest of the molecule. The model for the peptide-free conformation was evaluated using conformationally-sensitive antibody and superantigen probes predicted to show no change, moderate change, or dramatic changes in their interaction with peptide-free DR1 and peptide-loaded DR1. The binding observed for these probes is in agreement with the movements predicted by the model. Conclusion/Significance: This work presents a molecular model for peptide-free class II MHC proteins that can help to interpret the conformational changes known to occur within the protein during peptide binding and release, and ca
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