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1.
FASEB J ; 34(1): 571-587, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31914586

RESUMEN

Beyond the study of its transcriptional target genes, the identification of the various interactors of a transcription factor (TF) is crucial to understand its diverse cellular roles. We focused on FOXL2, a winged-helix forkhead TF important for ovarian development and maintenance. FOXL2 has been implicated in diverse cellular processes, including apoptosis, the control of cell cycle or the regulation of steroid hormone synthesis. To reliably identify partners of endogenous FOXL2, we performed a proteome-wide analysis using co-immunoprecipitation in the murine granulosa cell-derived AT29c and the pituitary-derived alpha-T3 cell lines, using three antibodies targeting different parts of the protein. Following a stringent selection of mass spectrometry data on the basis of identification reliability and protein enrichment, we identified a core set of 255 partners common to both cell lines. Their analysis showed that we could co-precipitate several complexes involved in mRNA processing, chromatin remodeling and DNA replication and repair. We further validated (direct and/or indirect) interactions with selected partners, suggesting an unexpected role for FOXL2 in those processes. Overall, this comprehensive analysis of the endogenous FOXL2 interactome sheds light on its numerous and diverse interactors and unconventional cellular roles.


Asunto(s)
Proteína Forkhead Box L2/metabolismo , Células de la Granulosa/metabolismo , Hipófisis/metabolismo , Mapas de Interacción de Proteínas , Proteoma/metabolismo , Animales , Células Cultivadas , Femenino , Células de la Granulosa/citología , Ratones , Hipófisis/citología , Proteoma/análisis
2.
World Hosp Health Serv ; 52(3): 29-33, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-30707811

RESUMEN

Available infrastructure, resources, and provided services in low-and middle-income countries differ significantly from high-income countries. In healthcare for example, the uneven distribution of health professionals and lack of human resources are real barriers to equitable access to quality health care and services in most developing countries and particularly in Sub-Saharan Africa. As available resources are lower and infrastructure is les developed many services and tools that have been developed for a high-income context cannot be used or are not sustainably affordable in a low-income environment, which led to the development of tools and services that are affordable and appropriate for this context. This ranges from concepts of blended learning, over tools for distance education and diagnostic to hardware like affordable and robust ultrasound machines and services like mobile payment. Many of these solutions and tools also have a great potential to be utilized in a different context and some of them have been deployed in high-income countries.


Asunto(s)
Internet , Aprendizaje Basado en Problemas , Telemedicina , África del Sur del Sahara , Países en Desarrollo , Accesibilidad a los Servicios de Salud
3.
J Gen Intern Med ; 28 Suppl 3: S666-70, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23780652

RESUMEN

BACKGROUND: There are large disparities in access to health-care professionals (HCP) in low-income African countries, leading to imbalanced and suboptimal health delivery. Part of the difficulty is recruiting and retaining care professionals to work in isolated settings. AIM: To evaluate the impact of distance continuing education as a way to build capacity, increase satisfaction and enhance the performance of care professionals in these isolated health-care facilities. SETTING: Care professionals using RAFT (Telemedicine Network in French-speaking Africa) in isolated care facilities. PROGRAM DESCRIPTION: Within RAFT, an organizational framework and computer-based tools have been developed and evolved to provide useful, qualitative, applicable training material. PROGRAM EVALUATION: The activity, satisfaction, perceptions and impact of RAFT on remote health-care workers are being monitored. RAFT's potential to improve the recruitment, satisfaction and retention of care professionals in remote settings is widely recognized; however, the actual impact on the performance and quality of care remains to be demonstrated.


Asunto(s)
Educación Continua/métodos , Educación a Distancia/métodos , Personal de Salud/educación , Investigadores/educación , Telemedicina/métodos , Adulto , África , Actitud del Personal de Salud , Femenino , Humanos , Satisfacción en el Trabajo , Masculino , Persona de Mediana Edad , Selección de Personal , Reorganización del Personal/estadística & datos numéricos , Evaluación de Programas y Proyectos de Salud
4.
Chromosome Res ; 20(8): 1033-44, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23149575

RESUMEN

Subterminal lampbrush loops of one of the 12 bivalents of the oocyte karyotype of Pleurodeles waltl (Amphibian, Urodele) underwent prominent morphological changes upon in vitro culture. These loops exhibited a fine ribonucleoprotein (RNP) granular matrix, which evolved during culture into huge structures that we have named 'chaussons' (slippers). This phenomenon involved progressive accumulation of proteins in the RNP matrix without protein neosynthesis. One of these proteins, which translocated into the nucleus during the culture, was identified as a homolog of the human Ro52 E3 ubiquitin ligase. RNA polymerase III was also found to accumulate on the same loops. These results suggest that the subterminal loops of bivalent XII act as a storage site for the components of a nuclear machinery involved in the quality control of RNA synthesis and maturation in response to cellular stress. They also emphasise the considerable value of the lampbrush chromosome system for a direct visualisation of modifications in gene expression and open the question of a nuclear accumulation of Ro52 in human or animal oocytes cultured in vitro for assisted reproductive technologies (ART).


Asunto(s)
Cromosomas/ultraestructura , Oocitos/metabolismo , Pleurodeles/genética , Ribonucleoproteínas/genética , Animales , Nucléolo Celular/química , Nucléolo Celular/genética , Cromosomas/genética , Femenino , Técnica del Anticuerpo Fluorescente , Expresión Génica , Cariotipificación , Oocitos/citología , ARN/genética , ARN/aislamiento & purificación , ARN Polimerasa III/genética , ARN Polimerasa III/metabolismo , Ribonucleoproteínas/metabolismo , Transcripción Genética , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo
5.
Nucleic Acids Res ; 39(10): 4109-21, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21278421

RESUMEN

A proteomic approach has enabled the identification of an orthologue of the splicing factor hnRNP G in the amphibians Xenopus tropicalis, Ambystoma mexicanum, Notophthalmus viridescens and Pleurodeles walt, which shows a specific RNA-binding affinity similar to that of the human hnRN G protein. Three isoforms of this protein with a differential binding affinity for a specific RNA probe were identified in the P. walt oocyte. In situ hybridization to lampbrush chromosomes of P. waltl revealed the presence of a family of hnRNP G genes, which were mapped on the Z and W chromosomes and one autosome. This indicates that the isoforms identified in this study are possibly encoded by a gene family linked to the evolution of sex chromosomes similarly to the hnRNP G/RBMX gene family in mammals.


Asunto(s)
Proteínas Anfibias/metabolismo , Ribonucleoproteína Heterogénea-Nuclear Grupo F-H/metabolismo , Proteínas Anfibias/química , Proteínas Anfibias/genética , Animales , Femenino , Genotipo , Ribonucleoproteína Heterogénea-Nuclear Grupo F-H/química , Ribonucleoproteína Heterogénea-Nuclear Grupo F-H/genética , Ribonucleoproteínas Nucleares Heterogéneas/química , Humanos , Familia de Multigenes , Oocitos/metabolismo , Péptidos/química , Péptidos/metabolismo , Pleurodeles/genética , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Sondas ARN , Cromosomas Sexuales
6.
Methods ; 51(1): 37-44, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20085818

RESUMEN

Due to their large size and fine organization, lampbrush chromosomes (LBCs) of amphibian oocytes have been for decades one of the favorite tools of biologists for the analysis of transcriptional and post-transcriptional processes at the cytological level. The emergence of the diploid Xenopus tropicalis amphibian as a model organism for vertebrate developmental genetics and the accumulation of sequence data made available by its recent genomic sequencing, strongly revive the interest of LBCs as a powerful tool to study genes expressed during oogenesis. We describe here a detailed protocol for preparing LBCs from X. tropicalis oocyte and give practical advice to encourage a large number of researchers to become familiar with these chromosomes.


Asunto(s)
Análisis Citogenético/métodos , Citogenética/métodos , Oocitos/metabolismo , Xenopus/metabolismo , Algoritmos , Animales , Cromosomas/ultraestructura , Análisis Citogenético/instrumentación , Diploidia , Femenino , Meiosis , Microscopía de Contraste de Fase/métodos , Modelos Genéticos , Procesamiento Postranscripcional del ARN , Análisis de Secuencia de ADN , Transcripción Genética
7.
Front Public Health ; 7: 188, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31334213

RESUMEN

The implementation of digital health technologies has increased globally, producing substantial amounts of information and knowledge. While there are still areas in digital health that are understudied, concurrently there is an exponential increase in published articles, guidelines, methods, projects, and experiences, many of which fail to reach critical mass (pilotitis). Semantically describing and documenting this implementation knowledge and the effectiveness of these tools will help to avoid the duplication of efforts, to reduce preventable implementation obstacles, and to assure that investments are targeted to the most important technological innovations. The RAFT annotation model, presented in this paper, enables to semantically describe all elements of various outputs and implementation projects that were developed, are used, or are part of the RAFT network. This model was initially developed to annotate various implementations and outputs of the RAFT network to facilitate knowledge documentation and sharing, and to be used as a proof of concept for the Implementome. The Implementome will be an interconnected knowledge system that enables the user to navigate on multiple dimensions through metadata annotated projects, people, and information, and can serve as base for consensus building, best practices and guidelines. The RAFT annotation model can be further developed to enable the annotation of outputs, implementations, people, initiatives, and projects of the digital health domain in general.

8.
BMJ Open ; 8(8): e022262, 2018 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-30121608

RESUMEN

OBJECTIVE: To identify interventions that could serve as reliable proxy indicators to measure eHealth impact on maternal and neonatal outcomes. DESIGN: Systematic review and Delphi study. METHODS: We searched PubMed, Embase and Cochrane from January 1990 to May 2016 for studies and reviews that evaluated interventions aimed at improving maternal/neonatal health and reducing mortality. Interventions that are not low-income and middle-income context appropriate and that cannot currently be diagnosed, managed or impacted by eHealth (eg, via telemedicine distance diagnostic or e-learning) were excluded. We used the Cochrane risk of bias, Risk Of Bias In Non- randomised Studies - of Interventions and ROBIS tool to assess the risk of bias. A three-step modified Delphi method was added to identify additional proxy indicators and prioritise the results, involving a panel of 13 experts from different regions, representing obstetricians and neonatologists. RESULTS: We included 44 studies and reviews, identifying 40 potential proxy indicators with a positive impact on maternal/neonatal outcomes. The Delphi experts completed and prioritised these, resulting in a list of 77 potential proxy indicators. CONCLUSIONS: The proxy indicators propose relevant outcome measures to evaluate if eHealth tools directly affect maternal/neonatal outcomes. Some proxy indicators require mapping to the local context, practices and available resources. The local mapping facilitates the utilisation of the proxy indicators in various contexts while allowing the systematic collection of data from different projects and programmes. Based on the mapping, the same proxy indicator can be used for different contexts, allowing it to measure what is locally and temporally relevant, making the proxy indicator sustainable. PROSPERO REGISTRATION NUMBER: CRD42015027351.


Asunto(s)
Países en Desarrollo , Salud del Lactante , Resultado del Embarazo , Telemedicina , Técnica Delphi , Países en Desarrollo/estadística & datos numéricos , Femenino , Humanos , Lactante , Salud del Lactante/estadística & datos numéricos , Mortalidad Infantil , Recién Nacido , Mortalidad Materna , Embarazo , Resultado del Embarazo/epidemiología
9.
FEMS Microbiol Lett ; 250(1): 63-9, 2005 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-16043312

RESUMEN

Cell structure modifications and beta-oxidation induction were monitored in two strains of Sporidiobolus, Sp. Ruinenii and Sp. pararoseus after cultivation on ricinoleic acid methyl ester. Ultrastructural observations of the yeast before and after cultivation on fatty acid esters did not reveal major modifications in Sp. ruinenii. Unexpectedly, in Sp. pararoseus a proliferation of the mitochondrion was observed. After induction, Sp. ruinenii principally exhibited an increase in the activities of acyl-CoA oxidase (ACO), hydroxyacyl-CoA deshydrogenase (HAD), thiolase and catalase. In contrast, Sp. pararoseus lacked ACO and catalase activities, but an increase in acyl-CoA deshydrogenase (ACDH) and enoyl-CoA hydratase (ECH) activity was observed. These data suggest that in Sp. ruinenii, beta-oxidation is preferentially localized in the microbody, whereas in Sp. pararoseus it might be localized in the mitochondria.


Asunto(s)
Basidiomycota/metabolismo , Basidiomycota/ultraestructura , Ácidos Grasos/metabolismo , Ácidos Ricinoleicos/metabolismo , 3-Hidroxiacil-CoA Deshidrogenasas/metabolismo , Acil-CoA Oxidasa/metabolismo , Aciltransferasas/metabolismo , Basidiomycota/crecimiento & desarrollo , Catalasa/metabolismo , Compartimento Celular , Enoil-CoA Hidratasa/metabolismo , Cinética , Microscopía Electrónica , Mitocondrias/metabolismo , Mitocondrias/ultraestructura , Oxidación-Reducción , Especificidad de la Especie
10.
Fundam Clin Pharmacol ; 17(6): 709-15, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15015716

RESUMEN

Glyceryl trinitrate (GTN) is commonly delivered by a patch for the treatment of angina pectoris. The idea is now generally accepted that GTN requires a biotransformation process that activates the drug, in particular through nitric oxide (NO) generation. However, the pharmacokinetics of NO delivery from GTN still remains obscure. The objective of this study was to assess GTN-derived NO formation in vascular tissues and organs in rabbit given GTN patches. NO levels were evaluated in rabbits after 3 h of treatment with a 10 mg GTN patch (GTN group; n = 7) or a placebo patch (CTL; n = 7). Nitrosylhaemoglobin (HbNO) was evaluated by electron spin resonance (ESR) spectroscopy in red cell suspension. In vivo spin trapping technique using FeMGD as a spin trap, associated with ESR was used to quantify NO in tissues. The NO-spin trap complex, which is a relatively stable product, has been measured in several tissues. The ESR spectrum corresponding to HbNO was not found in red cell of GTN or CTL rabbits. The spectrum corresponding to the NO-spin trap complex was observed in all analysed tissues of CTL rabbits. The signal was significantly increased in liver, renal medulla, heart left ventricle and spleen of GTN-treated rabbits, and to a lesser extent in right ventricle and lung. No difference was shown between NO-spin trap levels measured in aorta or inferior vena cava from GTN or CTL rabbits. These data suggest that GTN patch treatment induced NO release, and that tissue-specific differences in transdermal GTN-derived NO exist. The GTN-NO pathway appears to be largely involved in organs such as the liver, kidney and heart.


Asunto(s)
Administración Cutánea , Óxido Nítrico/biosíntesis , Óxido Nítrico/sangre , Nitroglicerina/farmacocinética , Sorbitol/análogos & derivados , Detección de Spin/métodos , Animales , Aorta Torácica/efectos de los fármacos , Aorta Torácica/metabolismo , Presión Sanguínea/efectos de los fármacos , Presión Sanguínea/fisiología , Formas de Dosificación , Compuestos Ferrosos/química , Frecuencia Cardíaca/efectos de los fármacos , Frecuencia Cardíaca/fisiología , Ventrículos Cardíacos/química , Ventrículos Cardíacos/efectos de los fármacos , Ventrículos Cardíacos/metabolismo , Hemoglobinas/química , Inyecciones Intravenosas , Riñón/química , Riñón/efectos de los fármacos , Riñón/metabolismo , Hígado/química , Hígado/efectos de los fármacos , Hígado/metabolismo , Nitratos/sangre , Óxido Nítrico/farmacocinética , Nitritos/sangre , Nitroglicerina/administración & dosificación , Nitroglicerina/metabolismo , Especificidad de Órganos/efectos de los fármacos , Especificidad de Órganos/fisiología , Conejos , Sorbitol/agonistas , Sorbitol/metabolismo , Sorbitol/farmacología , Marcadores de Spin , Bazo/química , Bazo/efectos de los fármacos , Bazo/metabolismo , Tiocarbamatos/agonistas , Tiocarbamatos/metabolismo , Tiocarbamatos/farmacología , Factores de Tiempo , Vasodilatadores/administración & dosificación , Vasodilatadores/metabolismo , Vasodilatadores/farmacocinética , Vena Cava Inferior/efectos de los fármacos , Vena Cava Inferior/metabolismo
11.
Vet Clin North Am Small Anim Pract ; 44(3): 629-32, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24766703

RESUMEN

For many medications, the pharmacokinetics and pharmacodynamics in pets have not been established and even where studies have been done, there is widespread species and individual variation. Practitioners should start with the lower end of the dose range and titrate up to maximum doses where there is insufficient therapeutic effect and no adverse effects or contraindications. Complete blood count, serum chemistry profile, and urinalysis should be performed before initiating the use of any medication, especially with off-label medications. Pharmacologic intervention for the treatment of behavior problems should be considered just one aspect of a comprehensive behavioral management and treatment protocol.


Asunto(s)
Conducta Animal/efectos de los fármacos , Gatos , Fármacos del Sistema Nervioso Central/administración & dosificación , Fármacos del Sistema Nervioso Central/uso terapéutico , Perros , Animales
12.
Front Public Health ; 2: 180, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25340048

RESUMEN

BACKGROUND: The objectives of this paper are to (i) provide an overview of the educational and clinical experiences of the Réseau en Afrique Francophone pour la Télémédecine (RAFT) network, (ii) analyze key challenges and lessons learnt throughout a decade of activity, and (iii) draw a vision and perspectives of its sustainability. METHODS: The study was carried out following three main stages: (i) a literature review, (ii) the analysis of key documents, and (iii) discussions with key collaborators of the RAFT. RESULTS: Réseau en Afrique Francophone pour la Télémédecine has been offering an important quantity of educational, clinical, and public health activities during the last decade. The educational activities include the weekly delivery of video-lectures for continuing and post-graduate medical education, the use of virtual patients for training in clinical decision making, research training activities using ICTs and other e-learning activities. The clinical and public health activities include tele-expertise to support health professionals in the management of difficult clinical cases, the implementation of clinical information systems in African hospitals, the deployment of mHealth projects, etc. Since 2010, the RAFT has been extended to the Altiplano in Bolivia and Nepal (in progress). Lessons Learnt and Perspectives: Important lessons have been learnt from the accumulated experiences throughout these years. These lessons concern: social and organization, human resources, technologies and data security, policy and legislation, and economy and financing. Also, given the increase of the activities and the integration of eHealth and telemedicine in the health system of most of the countries, the RAFT network faces many other challenges and perspectives such as learning throughout life, recognition, and valorization of teaching or learning activities, the impact evaluation of interventions, and the scaling up and transferability out of Africa of RAFT activities. Based on the RAFT experience, effective integration and optimum use of eHealth and telemedicine in low- and middle-income countries (LMICs) health systems should take into account the context (resources, infrastructure, and funding), the needs of key stakeholders, and the results derived from theoretical and practical experience. The relevant items highlighted to illustrate the sustainability of the RAFT network and the analyses performed in this study, should serve as discussion basis for the development of eHealth and telemedicine in LMICs.

13.
Stud Health Technol Inform ; 192: 1099, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23920873

RESUMEN

Traditionally, participation of African researchers in top Biomedical Informatics (BMI) scientific journals and conferences has been scarce. Looking beyond these numbers, an educational goal should be to improve overall research and, therefore, to increase the number of scientists/authors able to produce and publish high quality research. In such scenario, we are carrying out various efforts to expand the capacities of various institutions located at four African countries - Egypt, Ghana, Cameroon and Mali - in the framework of a European Commission-funded project, AFRICA BUILD. This project is currently carrying out activities such as e-learning, collaborative development of informatics tools, mobility of researchers, various pilot projects, and others. Our main objective is to create a self-sustained South-South network of BMI developers.


Asunto(s)
Investigación Biomédica/educación , Investigación Biomédica/organización & administración , Países en Desarrollo , Cooperación Internacional , Informática Médica/educación , Informática Médica/organización & administración , Apoyo Social , Camerún , Egipto , Ghana , Malí
15.
Nucleus ; 1(1): 109-22, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21327109

RESUMEN

The heterogenous nuclear ribonucleoprotein G (hnRNP G) controls the alternative splicing of several pre-mRNas. While hnRNP G displays an amino terminal RNA recognition motif (RRM), we find that this motif is paradoxically not implicated in the recruitment of hnRNP G to nascent transcripts in amphibian oocytes. In fact, a deletion analysis revealed that targeting of hnRNP G to active transcription units depends on another domain, centrally positioned, and consisting of residues 186-236. We show that this domain acts autonomously and thus is named NTD for nascent transcripts targeting domain. Furthermore, using an RNA probe previously characterized in vitro as an RNA that interacts specifically with hnRNP G, we demonstrate a new auxiliary RNA binding domain (RBD). It corresponds to a short region of 58 residues positioned at the carboxyl terminal end of the protein, which recognizes an RNA motif predicted to adopt an hairpin structure. The fact that the NTD acts independently from both the RRM and the RBD strongly suggests that the initial recruitment of hnRNP G to nascent pre-mRNAs is independent of its sequence-specific RNA binding properties. Together, these findings highlight the modular organization of hnRNP G and offer new insights into its multifunctional roles.


Asunto(s)
Ribonucleoproteínas Nucleares Heterogéneas/metabolismo , ARN/metabolismo , Secuencia de Aminoácidos , Animales , Sitios de Unión , Células HeLa , Ribonucleoproteínas Nucleares Heterogéneas/química , Ribonucleoproteínas Nucleares Heterogéneas/genética , Humanos , Datos de Secuencia Molecular , Motivos de Nucleótidos , Oocitos/metabolismo , Unión Proteica , Estructura Terciaria de Proteína , ARN/química , ARN Polimerasa II/metabolismo , Precursores del ARN/metabolismo , Sondas ARN/metabolismo , Alineación de Secuencia , Xenopus/metabolismo
16.
Dev Dyn ; 238(6): 1492-501, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19334284

RESUMEN

The amphibian Xenopus tropicalis, whose genome has been recently sequenced, has become an important model organism for vertebrate developmental genetics. The development of cytogenetic tools in this new model organism should contribute to an understanding of the organization of the amphibian genome and the mapping of a variety of loci of interest. In this respect, oocyte lampbrush chromosomes are particularly useful for the localization of genomic sequences expressed during oogenesis. We have constructed a working map of X. tropicalis lampbrush chromosomes, which allows the 10 bivalents of the oocyte karyotype to be readily identified by distinctive combinations of specific landmark structures composed of lateral loops, spheres, and granules. We have also established the patterns of RNA Pol III sites over the chromosomes by immunofluorescence using antibodies directed against two Pol III subunits. Specific staining patterns were found for each chromosome, which constitute a supplementary tool for their identification. Developmental Dynamics 238:1492-1501, 2009. (c) 2009 Wiley-Liss, Inc.


Asunto(s)
Mapeo Cromosómico/métodos , Cromosomas , Análisis Citogenético/métodos , Xenopus/genética , Animales , Cromosomas/genética , Cromosomas/ultraestructura
18.
Mol Cell Biochem ; 294(1-2): 225-35, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16871360

RESUMEN

OBJECTIVE: Hypercholesterolemia (HC) has been associated with impairment of vascular and myocardial functions. As HC could generate an alteration in the oxidative status, we studied the effects of a 1-month cholesterol diet on cardiovascular oxidative stress. METHODS AND RESULTS: New Zealand rabbits received cholesterol (1%) or normal chow for 1 month. At 30 days, superoxide anion levels, assessed by ESR spectroscopy, NAD(P)H oxidase (NOX) activity, and dihydroethidium (DHE) staining of aortas were higher in the cholesterol-fed (CF) group compared with control (respectively, 4.0 +/- 0.6 Arbitrary Units/mg (AU/mg) vs. 2.6 +/- 0.3, p < 0.05; 4231 +/- 433 vs. 2931 +/- 373 AU/mg, p<0.05; 21.4 +/- 1.2 vs. 12.9 +/- 1.7% fluorescence/mm2, p < 0.001). NOX gp91 phox and p67 phox expression in the aortas were higher in the CF group vs. control (1.5 +/- 0.2 vs. 0.5 +/- 0.2, p < 0.001; 0.9 +/- 0.2 vs. 0.3 +/- 0.2, p<0.05). The endothelium-dependent relaxation evaluated on the iliac arteries was higher in control than in the CF group (64.8 +/- 10.1 vs. 13.1 +/- 3.70%, p<0.001). The cardiac diastolic pressure estimated on isolated hearts was higher in the CF group than in control (21.1 +/- 4.1 vs. 10.3 +/- 1.4 mmHg, p<0.05) after 60 min of ischemia. CONCLUSIONS: Hypercholesterolemia induced increased levels of superoxide in the aortas and a higher expression of NOX subunits, associated with altered vasorelaxation. The increased diastolic pressure observed in hearts, consistent with a post-ischemic contractile dysfunction might be mediated by the production of superoxide.


Asunto(s)
Aterosclerosis/fisiopatología , Sistema Cardiovascular/fisiopatología , Superóxidos/metabolismo , Acetilcolina/farmacología , Animales , Aorta Abdominal/enzimología , Aorta Abdominal/metabolismo , Aterosclerosis/etiología , Aterosclerosis/patología , Colesterol/sangre , HDL-Colesterol/sangre , Dieta Aterogénica , Modelos Animales de Enfermedad , Espectroscopía de Resonancia por Spin del Electrón , Histocitoquímica , Hipercolesterolemia/metabolismo , Hipercolesterolemia/patología , Arteria Ilíaca/efectos de los fármacos , Arteria Ilíaca/fisiopatología , Luminiscencia , Masculino , Isquemia Miocárdica/etiología , Isquemia Miocárdica/metabolismo , Isquemia Miocárdica/fisiopatología , NADPH Oxidasas/análisis , Conejos , Vasodilatadores/farmacología
19.
Cell Mol Biol (Noisy-le-grand) ; 48 Online Pub: OL267-70, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12643443

RESUMEN

The aim of this study was 1/ to assess the efficacy of calpain inhibitors: leupeptin and calpain inhibitor-1, to inhibit calpain activity in vitro, 2/ to measure the scavenging abilities of these compounds against free radicals. The efficacy of calpain inhibitors to block calpain activity was tested with azocasein as a substrate for calpain. Leupeptin and calpain inhibitor-1 inhibited calpain activity in the same range of concentrations, the IC50 being 0.14 microM and 0.09 microM, respectively. We measured the antioxidant properties of leupeptin and calpain inhibitor-1 using the allophycocyans assay after identification offree radical species produced by the complex H2O2 + Cu(++). Electron paramagnetic resonance (EPR) spin-trapping studies performed by using DMPO showed that a quartet signal (hyperfine couplings aN = aH = 14.9 G) arisen from DMPO-OH was formed. We found a correlation between leupeptin concentration and oxygen radical absorbance capacity (ORAC) values (r2 = 0.975) indicating an in vivo antioxidant capacity. In contrast, calpain inhibitor-1 showed no protection. In conclusion, our findings indicate that leupeptin and calpain inhibitor-1 are equipotent inhibitors on calpain activity but exhibit diffrent antioxidant efficacy.


Asunto(s)
Antioxidantes/farmacología , Calpaína/antagonistas & inhibidores , Glicoproteínas/farmacología , Leupeptinas/farmacología , Espectroscopía de Resonancia por Spin del Electrón , Cinética , Ficocianina/farmacología
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