1,016 research outputs found
Impaired Mitophagy and Protein Acetylation Levels in Fibroblasts from Parkinson's Disease Patients
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
Primary culture of Rhodnius prolixus (Hemiptera: Reduviidae) salivary gland cells
In the present paper, we developed a primary culture of Rhodnius prolixus salivary gland and main salivary canal cells. Cells remained viable in culture for 30 days. Three types of cells were indentified in the salivary gland cultures, with binuclear cells being the most abundant. The supernatants of salivary cultures contained mainly 16-24 kDa proteins and presented anticoagulant and apyrase activities. Secretion vesicles were observed budding from the cellular monolayer of the main salivary canal cells. These results indicate that R. prolixus salivary proteins may be produced in vitro and suggest that the main salivary canal may have a possible secretory role
Tumor necrosis factor-α-mediated threonine 435 phosphorylation of p65 nuclear factor-κB subunit in endothelial cells induces vasogenic edema and neutrophil infiltration in the rat piriform cortex following status epilepticus
<p>Abstract</p> <p>Background</p> <p>Status epilepticus (SE) induces severe vasogenic edema in the piriform cortex (PC) accompanied by neuronal and astroglial damages. To elucidate the mechanism of SE-induced vasogenic edema, we investigated the roles of tumor necrosis factor (TNF)-α in blood-brain barrier (BBB) disruption during vasogenic edema and its related events in rat epilepsy models provoked by pilocarpine-induced SE.</p> <p>Methods</p> <p>SE was induced by pilocarpine in rats that were intracerebroventricularly infused with saline-, and soluble TNF p55 receptor (sTNFp55R) prior to SE induction. Thereafter, we performed Fluoro-Jade B staining and immunohistochemical studies for TNF-α and NF-κB subunits.</p> <p>Results</p> <p>Following SE, most activated microglia showed strong TNF-α immunoreactivity. In addition, TNF p75 receptor expression was detected in endothelial cells as well as astrocytes. In addition, only p65-Thr435 phosphorylation was increased in endothelial cells accompanied by SMI-71 expression (an endothelial barrier antigen). Neutralization of TNF-α by soluble TNF p55 receptor (sTNFp55R) infusion attenuated SE-induced vasogenic edema and neuronal damages via inhibition of p65-Thr435 phosphorylation in endothelial cells. Furthermore, sTNFp55R infusion reduced SE-induced neutrophil infiltration in the PC.</p> <p>Conclusion</p> <p>These findings suggest that impairments of endothelial cell functions via TNF-α-mediated p65-Thr 485 NF-κB phosphorylation may be involved in SE-induced vasogenic edema. Subsequently, vasogenic edema results in extensive neutrophil infiltration and neuronal-astroglial loss.</p
Entrepreneurial intentions and entrepreneurship education to University students in Portugal
[EN] This article analyzes entrepreneurial intentions and motivations that encourage university students of Tourism to create their own company. Methodology is based on an empirical study, using a questionnaire adapted from a model of Veciana and Urbano (Actitudes de los estudiantes universitarios hacia la creación de empresas: un estudio empírico comparativo entre Catalunya y Puerto Rico. El emprendedor innovador y la creación de empresas de I + D + I, University of Valencia, pp 35 58, 2004), including the desirability and viability concepts. One hundred and sixty students answered the questionnaire from a total study population of 243 official Tourism degree students of the Superior Institute of Accounting and Management of Porto. This research finds out that the university students have a very positive perception about the desire to create their own company; a 90 % of students express their desire to do it, and 83.5 % express their intention. Moreover, a 57.5 % think that within actual crisis it is more difficult to do than before it. This research lets us get an in-depth study of a student of Tourism degree, finding out his entrepreneurial attitudes. It can be the first step to wake up and encourage students interest for starting up their own business.Del Rio-Rama, MDLC.; Peris-Ortiz, M.; Álvarez García, J.; Rueda Armengot, C. (2016). Entrepreneurial intentions and entrepreneurship education to University students in Portugal. Technology, Innovation and Education. 2(7):1-11. doi:10.1186/s40660-016-0013-5S11127Ajzen I (1991) The theory of plannes behavior. Organ Behav Hum Decis Process 50:179–211Aponte M (2002) Factores condicionantes de la creación de empresas en Puerto Rico: un enfoque institucional. Doctoral dissertation, Autonomous University of BarcelonaAponte M, Urbano D, Veciana JM (2006) Actitudes hacia la creación de empresas: un estudio comparativo entre Catalunya y Puerto Rico. Centro de Investigaciones Comerciales e Iniciativas Académicas de la Facultad de Administración de Empresas. Forum Empresarial 11(2):52–75Bae TJ, Qian S, Miao C, Fiet JO (2014) The relationship between entrepreneurship education and entrepreneurial intentions: a meta-analytic review. Entrep Theory Pract 38(2):217–254Brice J (2004) The role of personality dimensions on the formation of entrepreneurial intentions. USASBE Small Business Advancement National Center. University of Central Arkansas, USACabana-Villca R, Cortes-Castillo I, Plaza-Pasten D, Castillo-Vergara M, Alvarez-Marin A (2013) Análisis de las capacidades emprendedoras potenciales y efectivas en alumnos de centros de educación superior. J Technol Manag Innov 8(1):65–75Davidsson P (1989) Continued entrepreneurship and small firm business. Stockholm School of Economics, StockholmDavidsson P (1995) Culture, structure and regional levels of entrepreneurship. Entrep Reg Dev 7(1):41–62De Jorge-Moreno J, Castillo LL, Triguero MS (2012) The effect of business and economics education programs on students’ entrepreneurial intention. Eur J Train Dev 36(4):409–425Díaz JC, Hernández RM, Barata ML (2007) Estudiantes universitarios y creación de empresas. Un análisis comparativo entre España y Portugal. In Ayala, J.C. (coord.) Conocimiento, innovación y emprendedores: camino al futuro. Grupo FEDRA, MadridDo Paço AMF, Ferreira JM, Raposo M, Rodrigues RG, Dinis A (2011) Behaviours and entrepreneurial intention: empirical findings about secondary students. J Int Entrep 9(1):20–38Dohse D, Walter SG (2010) The role of entrepreneurship education and regional context in forming entrepreneurial intentions (No. 2010, 18). Document de treball de l’IEBEuropean Commission (2006). Entrepreneurship education in Europe: Fostering entrepreneurial mindsets through education and learning, Final Proceedings of the Conference on Entrepreneurship Education in OsloEurostat (2014) Informes sobre el empleo en la Unión Europea. Available in: http://europa.eu/publications/statistics/index_es.htmFuentes F, Saco F, Rodríguez P (2013) Estudio sobre el perfil emprendedor en el alumnado universitario de Córdoba. UCO Consejo Social de la Universidad de Córdoba, III Edición, Córdoba, pp 1–180Fuentes García FJ (2007) Análisis del Perfil Emprendedor del alumnado universitario y preuniversitario de Córdoba. Consejo Social Universidad de Córdoba, pp 1–105Genesca Garrigosa E, Veciana Verges JM (1984) Actitudes hacia la creación de empresas. Información Comercial Española 611:147–155Gerba DT (2012) Impact of entrepreneurship education on entrepreneurial intentions of business and engineering students in Ethiopia. Afr J Econ Manag Stud 3(2):258–277Gorman G, Hanlon D, King W (1997) Some research perspectives on entrepreneurship education and education for small business management: a ten-year literature review. Int Small Bus J 15(3):56–77Guerrero M, Rialp J, Urbano D (2008) The impact of desirability and feasibility on entrepreneurial intentions: a structural equation model. Int Entrep Manag J 4(1):35–50Haynie JM, Shepherd DA, McMullen JS (2009) An opportunity for me? The role of resources in opportunity evaluation decisions. J Manage Stud 46(3):337–361Hernangomez J, Martín N, Rodriguez AI, Saboia F (2005) El emprendedor nace o se hace? Un análisis de los determinantes del espíritu emprendedor. XVI Spanish-Portuguese Meeting of Scientic Management. Sevilla:33–44Hmieleski KM, Corbett AC (2006) Proclivity for improvisation as a predictor of entrepreneurial intentions. J Small Bus Manage 44(1):45–63Honjo Y (2004) Growth of new start-up firms: evidence from the Japanese manufacturing industry. Appl Econ Lett 11(1):21–32Hyde GC (1989) The relationship between policy and research. In Rosa, P.; Birley, S. Cannon, T. and O´Neill, K. The Role and Contribution of Small Business Research, Chap. 3:55–77, Institute ReportKolvereid L (1996) Prediction of employment status choice intentions. Entrep Theory Pract 21(1):47–57Kourilsky ML, Walstad WB (1998) Entrepreneurship and female youth: knowledge, attitude, gender differences, and educational practices. J Bus Ventur 13(1):77–88Krueger N, Brazeal D (1994) Entrepreneurial Potencial and Potencial Entrepreneurs. Entrep Theory Pract 18(3):91–104Krueger NF, Carsrud AL (1993) Entrepreneurial intentions: applying the theory of planned behaviour. Entrep Reg Dev 5(4):315–330Lanero A, Vázquez JL, Gutiérrez P, García MP (2011) The impact of entrepreneurship education in European universities: an intention-based approach analyzed in the Spanish area. Int Rev Public Nonprofit Marketin 8(2):111–130Miller BK, Bell JD, Palmer M, González A (2009) Predictors of entrepreneurial intentions: a quasi-experiment comparing students enrolled in introductory management and entrepreneurship classes. J Bus Entrep 21(2):39–62Neck HM, Zacharakis AL, Bygrave WD, Reynolds PD (2003) Global entrepreneurship monitor: 2002 executive report. Babson College, Babson, MANorth DC (1990) Institutions, Institutional Change and Economic Performance. Cambridge University Press, Cambridge (UK)North D (1993) Instituciones, cambio institucional y desempeño económico. Fondo de Cultura Económica, MéxicoNorth DC (2005) Understanding the Process of Economic Change. Academic Foundation. University Press, PrincentonGEM Portugal (2012) Estudo sobre o Empreendedorismo. Global Entrepreneruship Monitor (GEM). Instituto Universitário de Lisboa (ISCTEIUL) http://web.spi.pt/GEMportugal2012/files/GEM_PORTUGAL_2012.pdfRaposo M, do Paço A, Ferreira J (2008a) Entrepreneur’s profile: a taxonomy of attribu tes and motivations of university students. J Small Bus Enterp Dev 15(2):405–420Raposo MLB, Ferreira JJM, do Paço AMF, Rodrigues RJG (2008b) Propensity to firm creation: empirical research using structural equations. Int Entrep Manag J 4(4):485–504Robinson PB, Stimpson DV, Huefner JC, Hunt HK (1991) An attitude approach to the prediction of entrepreneurship. Entrep Theory Pract 15(4):13–31Samad Aghayi J (2008) Entrepreneurship organization. Public Administration Training Center Publications, TehranScherer RF, Adams JS, Carley S, Wiebe FA (1989) Role model performance effects on development of entrepreneurial career preference. Entrep Theory and Pract, spring:53–71Scherer RF, Brodzinski JD, Wiebe F (1991) Examining the relationship between personality and entrepreneurial career preference. Entrep Reg Dev 3(2):195–206Shane S (2003) A General Theory of Enttrepreneurship- The Individual Oportunity Nexus. Edward Elgar EditoresShapero A (1982) Social dimensions of entrepreneurship. In: Kent CA et al (eds) The encyclopedia of entrepreneurship. Prentice-Hall, Englewood Cliffs, pp 72–89Shapero A, Sokol L (1982) The social dimensions of entrepreneurship.Encyclopedia of Entrepreneurship:72–90Storey DJ (1994) Employment. In Storey, D.J. Understanding the small business sector. Capítulo 6, pp. 160–203. London: RoutledgeToledano N, Urbano D (2008) Promoting entrepreneurial mindsets at universities: a case study in the South of Spain. Eur J Int Manag 2(4):382–399Trequattrini R, Lombardi R, Lardo A, Cuozzo B (2015). The Impact of Entrepreneurial Universities on Regional Growth: a Local Intellectual Capital Perspective. Journal of the Knowledge Economy, 1–13Urbano D (2006) La creación de empresas en Catalunya. Organismos de apoyo y actitudes hacia la actividad emprendedora, Ed. Generalitat de Catalunya-CIDEM, BarcelonaUrbano D, Toledano N (2008) The systems of university education and their influence on the students’ attitudes in the business world: a multiple case study. Oikos 25:87–103Veciana JM (1989) Características del empresario en España. Papeles de Economía Española 39:19–36Veciana JM, Urbano D (2004) Actitudes de los estudiantes universitarios hacia la creación de empresas: un estudio empírico comparativo entre Catalunya y Puerto Rico. El emprendedor innovador y la creación de empresas de I + D + I, University of Valencia, pp 35–58Veciana JM, Aponte M, Urbano D (2005) University student’s attitudes towards entrepreneurship: a two countries comparison. Int Entrep Manag J 1:165–182Wang CK, Wong PK (2004) Entrepreneurial interest of university students in Singapore. Technovation 24(2):163–172White SB, Reynolds PD (1996) Government programs and high growth new firms. Frontiers of Entrepreneurship Research. Center for Entrepreneurial Studies Babson College. Wellesley, MA.: 621–635Yari A, Toulabi Z, Pourashraf Y (2013) Designing propensity to entrepreneurship paradigm in Ilam universities (structural equation model approach). J Novel Appl Sci 2:872–88
Physicochemical and biological characterization of 1E10 Anti-Idiotype vaccine
<p>Abstract</p> <p>Background</p> <p>1E10 monoclonal antibody is a murine anti-idiotypic antibody that mimics N-glycolyl-GM3 gangliosides. This antibody has been tested as an anti-idiotypic cancer vaccine, adjuvated in Al(OH)<sub>3</sub>, in several clinical trials for melanoma, breast, and lung cancer. During early clinical development this mAb was obtained <it>in vivo </it>from mice ascites fluid. Currently, the production process of 1E10 is being transferred from the <it>in vivo </it>to a bioreactor-based method.</p> <p>Results</p> <p>Here, we present a comprehensive molecular and immunological characterization of 1E10 produced by the two different production processes in order to determine the impact of the manufacturing process in vaccine performance. We observed differences in glycosylation pattern, charge heterogeneity and structural stability between <it>in vivo</it>-produced 1E10 and bioreactor-obtained 1E10. Interestingly, these modifications had no significant impact on the immune responses elicited in two different animal models.</p> <p>Conclusions</p> <p>Changes in 1E10 primary structure like glycosylation; asparagine deamidation and oxidation affected 1E10 structural stability but did not affect the immune response elicited in mice and chickens when compared to 1E10 produced in mice.</p
Validation of diabetes mellitus and hypertension diagnosis in computerized medical records in primary health care
<p>Abstract</p> <p>Background</p> <p>Computerized Clinical Records, which are incorporated in primary health care practice, have great potential for research. In order to use this information, data quality and reliability must be assessed to prevent compromising the validity of the results.</p> <p>The aim of this study is to validate the diagnosis of hypertension and diabetes mellitus in the computerized clinical records of primary health care, taking the diagnosis criteria established in the most prominently used clinical guidelines as the gold standard against which what measure the sensitivity, specificity, and determine the predictive values.</p> <p>The gold standard for diabetes mellitus was the diagnostic criteria established in 2003 American Diabetes Association Consensus Statement for diabetic subjects. The gold standard for hypertension was the diagnostic criteria established in the Joint National Committee published in 2003.</p> <p>Methods</p> <p>A cross-sectional multicentre validation study of diabetes mellitus and hypertension diagnoses in computerized clinical records of primary health care was carried out. Diagnostic criteria from the most prominently clinical practice guidelines were considered for standard reference.</p> <p>Sensitivity, specificity, positive and negative predictive values, and global agreement (with kappa index), were calculated. Results were shown overall and stratified by sex and age groups.</p> <p>Results</p> <p>The agreement for diabetes mellitus with the reference standard as determined by the guideline was almost perfect (κ = 0.990), with a sensitivity of 99.53%, a specificity of 99.49%, a positive predictive value of 91.23% and a negative predictive value of 99.98%.</p> <p>Hypertension diagnosis showed substantial agreement with the reference standard as determined by the guideline (κ = 0.778), the sensitivity was 85.22%, the specificity 96.95%, the positive predictive value 85.24%, and the negative predictive value was 96.95%. Sensitivity results were worse in patients who also had diabetes and in those aged 70 years or over.</p> <p>Conclusions</p> <p>Our results substantiate the validity of using diagnoses of diabetes and hypertension found within the computerized clinical records for epidemiologic studies.</p
A study of the dry forest communities in the Dominican Republic
This paper is a floristic and phytosociological study of the dry forest communities of the Dominican Republic. A total of 69 relevés in dry forest biotopes were carried out. The samples were subsequently subjected to Detrended Correspondence Analysis for the determination and study of possible groupings. The study does not cover tree formations growing on serpentines, nor the so-called semideciduous forests, peculiar to areas with higher rainfall. A total of nine phytocoenoses were identified. The most significant results led to the description of six new phytosociological associations: Simaroubetum berteroani (thorny dry forest on coastal dunes), Phyllostylo rhamnoidis-Prosopidetum juliflorae (southern Dominican disturbed dry forest), Consoleo moniliformis-Camerarietum linearifoliae (dry forest on hard limestones), Lemaireocereo hystricis-Prosopidetum juliflorae (northern Dominican disturbed dry forest), Lycio americani-Prosopidetum juliflorae (disturbed dry forest on saline soils) and Guettardo ellipticae-Guapiretum discoloris (dry forest on flat-topped hillocks in Montecristi). This is an important step forward in the phytosociological and floristic studies of the Caribbean territories.Este trabalho apresenta um estudo florístico e fitossociológico das comunidades de florestas secas da República Dominicana. Um total de 69 amostras foram obtidas pelo método relevé em biótopos florestais secos. As amostras foram posteriormente submetidas à análise de correspondência destendenciada para a determinação e estudo de possíveis agrupamentos. O estudo não abrange formações arbóreas desenvolvidas sobre serpentinitos, nem as chamadas florestas semideciduais, peculiares às áreas de maior pluviosidade. Foram identificados nove fitocenoses. Os resultados mais significativos levaram à descrição de seis novas associações fitossociológicas: Simaroubetum berteroani (floresta espinhosa seca em dunas costeiras), Phyllostylo rhamnoidis-Prosopidetum juliflorae (floresta seca perturbada do sul da República Dominicana), Consoleo moniliformis-Camerarietum linearifoliae (floresta seca sobre calcários compactos), Lemaireocereo hystricis-Prosopidetum juliflorae (floresta seca perturbada do norte da República Dominicana), Lycio americani-Prosopidetum juliflorae (floresta seca perturbada desenvolvida em solos salinos) Guettardo ellipticae-Guapiretum discoloris (floresta seca em colinas de topo achatado em Montecristi). O trabalho realizado representa um importante avanço nos estudos fitossociológicos e florísticos dos territórios do Caribe.This research paper was possible thanks to the sponsorship of the Agencia Española de Cooperación Internacional para el Desarrollo (AECID), under the auspices of the Ministerio de Asuntos Exteriores y de Cooperación de España, which funded the project (cod. A/3499/05)
Metabolic and Hormonal Changes After Laparoscopic Roux-en-Y Gastric Bypass and Sleeve Gastrectomy: a Randomized, Prospective Trial
BACKGROUND: The mechanisms of amelioration of glycemic control early after laparoscopic Roux-en-Y gastric bypass (LRYGB) or laparoscopic sleeve gastrectomy (LSG) are not fully understood. METHODS: In this prospective, randomized 1-year trial, outcomes of LRYGB and LSG patients were compared, focusing on possibly responsible mechanisms. Twelve patients were randomized to LRYGB and 11 to LSG. These non-diabetic patients were investigated before and 1 week, 3 months, and 12 months after surgery. A standard test meal was given after an overnight fast, and blood samples were collected before, during, and after food intake for hormone profiles (cholecystokinin (CCK), ghrelin, glucagon-like peptide 1 (GLP-1), peptide YY (PYY)). RESULTS: In both groups, body weight and BMI decreased markedly and comparably leading to an identical improvement of abnormal glycemic control (HOMA index). Post-surgery, patients had markedly increased postprandial plasma GLP-1 and PYY levels (p > 0.05) with ensuing improvement in glucose homeostasis. At 12 months, LRYGB ghrelin levels approached preoperative values. The postprandial, physiologic fluctuation returned, however, while LSG ghrelin levels were still markedly attenuated. One year postoperatively, CCK concentrations after test meals increased less in the LRYGB group than they did in the LSG group, with the latter showing significantly higher maximal CCK concentrations (p > 0.012 vs. LRYGB). CONCLUSIONS: Bypassing the foregut is not the only mechanism responsible for improved glucose homeostasis. The balance between foregut (ghrelin, CCK) and hindgut (GLP-1, PYY) hormones is a key to understanding the underlying mechanisms
A Deep Insight into the Sialome of Rhodnius neglectus, a vector of chagas disease
Background Triatomines are hematophagous insects that act as vectors of Chagas disease. Rhodnius neglectus is one of these kissing bugs found, contributing to the transmission of this American trypanosomiasis. The saliva of hematophagous arthropods contains bioactive molecules responsible for counteracting host haemostatic, inflammatory, and immuneresponses. Methods/Principal Findings Next generation sequencing and mass spectrometry-based protein identification were performed to investigate the content of triatomine R. neglectus saliva.We deposited 4,230 coding DNA sequences (CDS) in GenBank. A set of 636 CDS of proteins of putative secretory nature was extracted from the assembled reads, 73 of them confirmed by proteomic analysis. The sialome of R. neglectus was characterized and serine protease transcripts detected. The presence of ubiquitous protein families was revealed, including lipocalins, serine protease inhibitors, and antigen-5. Metalloproteases, disintegrins, and odorant binding protein families were less abundant. Conclusions/Significance The data presented improve our understanding of hematophagous arthropod sialomes, and aid in understanding hematophagy and the complex interplay among vectors and their vertebrate hosts
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