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1.
J Orthop Traumatol ; 18(4): 439-450, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28921307

RESUMEN

BACKGROUND: To analyse the prevalences of the cam and pincer morphologies in a cohort of patients with groin pain syndrome caused by inguinal pathologies. MATERIALS AND METHODS: Forty-four patients (40 men and 4 women) who suffered from groin pain syndrome were enrolled in the study. All the patients were radiographically and clinically evaluated following a standardised protocol established by the First Groin Pain Syndrome Italian Consensus Conference on Terminology, Clinical Evaluation and Imaging Assessment in Groin Pain in Athlete. Subsequently, all of the subjects underwent a laparoscopic repair of the posterior inguinal wall. RESULTS: The study demonstrated an association between the cam morphology and inguinal pathologies in 88.6% of the cases (39 subjects). This relationship may be explained by noting that the cam morphology leads to biomechanical stress at the posterior inguinal wall level. CONCLUSIONS: Athletic subjects who present the cam morphology may be considered a population at risk of developing inguinal pathologies. LEVEL OF EVIDENCE: Level IV, Observational cross-sectional study.


Asunto(s)
Pared Abdominal/cirugía , Traumatismos en Atletas/fisiopatología , Traumatismos en Atletas/cirugía , Pinzamiento Femoroacetabular/fisiopatología , Ingle/cirugía , Adulto , Traumatismos en Atletas/diagnóstico por imagen , Fenómenos Biomecánicos , Estudios Transversales , Femenino , Pinzamiento Femoroacetabular/clasificación , Pinzamiento Femoroacetabular/diagnóstico por imagen , Pinzamiento Femoroacetabular/etiología , Hernia Inguinal/cirugía , Humanos , Laparoscopía , Masculino , Dolor/etiología , Dolor/fisiopatología , Método Simple Ciego , Mallas Quirúrgicas , Síndrome , Adulto Joven
2.
Circulation ; 124(8): 901-11, 1-7, 2011 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-21810660

RESUMEN

BACKGROUND: In animal models of cardiac arrest, the benefit afforded by hypothermia is closely linked to the rapidity of the decrease in body temperature after resuscitation. Because total liquid ventilation (TLV) with temperature-controlled perfluorocarbons induces a very rapid and generalized cooling, we aimed to determine whether this could limit the post-cardiac arrest syndrome in a rabbit model. We especially focused on neurological, cardiac, pulmonary, liver and kidney dysfunctions. METHODS AND RESULTS: Anesthetized rabbits were submitted to either 5 or 10 minutes of untreated ventricular fibrillation. After cardiopulmonary resuscitation and resumption of a spontaneous circulation, the animals underwent either normothermic life support (control) or therapeutic hypothermia induced by TLV. The latter procedure decreased esophageal and tympanic temperatures to 32°C to 33°C within only 10 minutes. After rewarming, the animals submitted to TLV exhibited an attenuated neurological dysfunction and decreased mortality 7 days later compared with control. The neuroprotective effect of TLV was confirmed by a significant reduction in brain histological damages. We also observed limitation of myocardial necrosis, along with a decrease in troponin I release and a reduced myocardial caspase 3 activity, with TLV. The beneficial effects of TLV were directly related to the rapidity of hypothermia induction because neither conventional cooling (cold saline infusion plus external cooling) nor normothermic TLV elicited a similar protection. CONCLUSIONS: Ultrafast cooling instituted by TLV exerts potent neurological and cardiac protection in an experimental model of cardiac arrest in rabbits. This could be a relevant approach to provide a global and protective hypothermia against the post-cardiac arrest syndrome.


Asunto(s)
Reanimación Cardiopulmonar , Fluorocarburos , Paro Cardíaco/terapia , Hipotermia Inducida/métodos , Daño por Reperfusión/prevención & control , Animales , Modelos Animales de Enfermedad , Corazón/fisiología , Paro Cardíaco/mortalidad , Paro Cardíaco/fisiopatología , Riñón/fisiología , Ventilación Liquida , Hígado/fisiología , Pulmón/fisiología , Fenómenos Fisiológicos del Sistema Nervioso , Conejos , Daño por Reperfusión/mortalidad , Daño por Reperfusión/fisiopatología , Factores de Tiempo , Fibrilación Ventricular/mortalidad , Fibrilación Ventricular/fisiopatología , Fibrilación Ventricular/terapia
3.
Cell Death Differ ; 15(1): 123-33, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17932501

RESUMEN

Increasing evidence provides support that mammalian liver contains stem/progenitor cells, but their molecular phenotype, embryological derivation, biology and their role in liver cell turnover and regeneration remain to be further clarified. In this study, we report the isolation, characterization and reproducible establishment in line of a resident liver stem cell (RLSC) with immunophenotype and differentiative potentiality distinct from other previously described liver precursor/stem cells. RLSCs, derived from fetal and neonatal murine livers as well as from immortalized hepatocytic MMH lines and established in lines, are Sca+, CD34-, CD45-, alpha-fetoprotein+ and albumin-. This molecular phenotype suggests a non-hematopoietic origin. RLSC transcriptional profile, defined by microArray technology, highlighted the expression of a broad spectrum of 'plasticity-related genes' and 'developmental genes' suggesting a multi-differentiative potentiality. Indeed, RLSCs spontaneously differentiate into hepatocytes and cholangiocytes and, when cultured in appropriate conditions, into mesenchymal and neuro-ectodermal cell lineages such as osteoblasts/osteocytes, chondrocytes, astrocytes and neural cells. RLSC capability to spontaneously differentiate into hepatocytes, the lack of albumin expression and the broad differentiative potentiality locate them in a pre-hepatoblast/liver precursor cells hierarchical position. In conclusion, RLSCs may provide a useful tool to improve liver stem cell knowledge and to assess new therapeutic approaches for liver diseases.


Asunto(s)
Hepatocitos/citología , Hígado/citología , Células Madre Multipotentes/citología , Animales , Animales Recién Nacidos , Diferenciación Celular , Linaje de la Célula , Separación Celular , Células Cultivadas , Condrocitos/citología , Perfilación de la Expresión Génica , Hepatocitos/metabolismo , Inmunofenotipificación , Hígado/embriología , Ratones , Células Madre Multipotentes/metabolismo , Neuronas/citología , Análisis de Secuencia por Matrices de Oligonucleótidos , Osteoblastos/citología , Fenotipo
4.
Leukemia ; 32(2): 438-449, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28745329

RESUMEN

Primary myelofibrosis (PMF) is a myeloproliferative neoplasm characterized by hyperplastic megakaryopoiesis and myelofibrosis. We recently described the upregulation of MAF (v-maf avian musculoaponeurotic fibrosarcoma oncogene homolog) in PMF CD34+ hematopoietic progenitor cells (HPCs) compared to healthy donor. Here we demonstrated that MAF is also upregulated in PMF compared with the essential thrombocytemia (ET) and polycytemia vera (PV) HPCs. MAF overexpression and knockdown experiments shed some light into the role of MAF in PMF pathogenesis, by demonstrating that MAF favors the megakaryocyte and monocyte/macrophage commitment of HPCs and leads to the increased expression of proinflammatory and profibrotic mediators. Among them, we focused our further studies on SPP1 and LGALS3. We assessed SPP1 and LGALS3 protein levels in 115 PMF, 47 ET and 24 PV patients plasma samples and we found that SPP1 plasma levels are significantly higher in PMF compared with ET and PV patients. Furthermore, in vitro assays demonstrated that SPP1 promotes fibroblasts and mesenchymal stromal cells proliferation and collagen production. Strikingly, clinical correlation analyses uncovered that higher SPP1 plasma levels in PMF patients correlate with a more severe fibrosis degree and a shorter overall survival. Collectively our data unveil that MAF overexpression contributes to PMF pathogenesis by driving the deranged production of the profibrotic mediator SPP1.


Asunto(s)
Médula Ósea/metabolismo , Médula Ósea/patología , Fibrosis/metabolismo , Fibrosis/patología , Osteopontina/metabolismo , Proteínas Proto-Oncogénicas c-maf/metabolismo , Antígenos CD34/metabolismo , Proliferación Celular/fisiología , Células Madre Hematopoyéticas/metabolismo , Células Madre Hematopoyéticas/patología , Humanos , Megacariocitos/metabolismo , Megacariocitos/patología , Trastornos Mieloproliferativos/metabolismo , Trastornos Mieloproliferativos/patología , Policitemia Vera/metabolismo , Policitemia Vera/patología , Mielofibrosis Primaria/metabolismo , Mielofibrosis Primaria/patología , Trombocitemia Esencial/metabolismo , Trombocitemia Esencial/patología
5.
Cell Death Differ ; 13(10): 1686-96, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16456583

RESUMEN

Upregulation of specific transcription factors is a generally accepted mechanism to explain the commitment of hematopoietic stem cells along precise maturation lineages. Based on this premise, transduction of primary hematopoietic stem/progenitor cells with viral vectors containing the investigated transcription factors appears as a suitable experimental model to identify such regulators. Although MafB transcription factor is believed to play a role in the regulation of monocytic commitment, no demonstration is, to date, available supporting this function in normal human hematopoiesis. To address this issue, we retrovirally transduced cord blood CD34+ hematopoietic progenitors with a MafB cDNA. Immunophenotypic and morphological analysis of transduced cells demonstrated the induction of a remarkable monomacrophage differentiation. Microarray analysis confirmed these findings and disclosed the upregulation of macrophage-related transcription factors belonging to the AP-1, MAF, PPAR and MiT families. Altogether our data allow to conclude that MafB is a key regulator of human monocytopoiesis.


Asunto(s)
Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/metabolismo , Factor de Transcripción MafB/genética , Factor de Transcripción MafB/metabolismo , Monocitos/citología , Monocitos/metabolismo , Antígenos CD34/metabolismo , Línea Celular , Ensayo de Unidades Formadoras de Colonias , ADN Complementario/genética , Sangre Fetal/citología , Sangre Fetal/inmunología , Sangre Fetal/metabolismo , Perfilación de la Expresión Génica , Células Madre Hematopoyéticas/inmunología , Humanos , Técnicas In Vitro , Recién Nacido , Factor de Transcripción MafB/antagonistas & inhibidores , Monocitos/inmunología , Mielopoyesis , Análisis de Secuencia por Matrices de Oligonucleótidos , ARN Interferente Pequeño/genética , Retroviridae/genética , Transducción Genética , Regulación hacia Arriba
6.
Leukemia ; 20(10): 1751-8, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16932344

RESUMEN

Acute myeloid leukemia (AML) blasts are immature committed myeloid cells unable to spontaneously undergo terminal maturation, and characterized by heterogeneous sensitivity to natural differentiation inducers. Here, we show a molecular signature predicting the resistance or sensitivity of six myeloid cell lines to differentiation induced in vitro with retinoic acid or vitamin D. The identified signature was further validated by TaqMan assay for the prediction of response to an in vitro differentiation assay performed on 28 freshly isolated AML blast populations. The TaqMan assay successfully predicts the in vitro resistance or responsiveness of AML blasts to differentiation inducers. Furthermore, performing a meta-analysis of publicly available microarray data sets, we also show the accuracy of our prediction on known phenotypes and suggest that our signature could become useful for the identification of patients eligible for new therapeutic strategies.


Asunto(s)
Antineoplásicos/farmacología , Resistencia a Antineoplásicos/genética , Leucemia Mieloide/tratamiento farmacológico , Leucemia Mieloide/genética , Tretinoina/farmacología , Enfermedad Aguda , Diferenciación Celular/efectos de los fármacos , Línea Celular Tumoral , Análisis por Conglomerados , Bases de Datos Factuales , Regulación Leucémica de la Expresión Génica/efectos de los fármacos , Humanos , Leucemia Mieloide/patología , Metaanálisis como Asunto , Análisis de Secuencia por Matrices de Oligonucleótidos , Valor Predictivo de las Pruebas , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Vitamina D/farmacología , Vitaminas/farmacología
7.
Cell Death Differ ; 12(12): 1588-600, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15947790

RESUMEN

In spite of their apparently restricted differentiation potentiality, hematopoietic precursors are plastic cells able to trans-differentiate from a maturation lineage to another. To better characterize this differentiation plasticity, we purified CD14- and CD14+ myeloid precursors generated by 'in vitro' culture of human CD34+ hematopoietic progenitors. Morphological analysis of the investigated cell populations indicated that, as expected, they consisted of granulocyte and monocyte precursors, respectively. Treatment with differentiation inducers revealed that CD14- cells were bipotent granulo-monocyte precursors, while CD14+ cells appeared univocally committed to a terminal macrophage maturation. Flow cytometry analysis demonstrated that the conversion of granulocyte precursors to the mono-macrophage maturation lineage occurs through a differentiation transition in which the granulocyte-related myeloperoxidase enzyme and the monocyte-specific CD14 antigen are co-expressed. Expression profiling evidenced that the observed trans-differentiation process was accompanied by a remarkable upregulation of the monocyte-related MafB transcription factor.


Asunto(s)
Antígenos CD34/inmunología , Diferenciación Celular/fisiología , Células Madre Hematopoyéticas/fisiología , Receptores de Lipopolisacáridos/inmunología , ARN Mensajero/metabolismo , Antígenos de Diferenciación/metabolismo , Linaje de la Célula , Células Cultivadas , Citometría de Flujo , Granulocitos/citología , Granulocitos/inmunología , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/inmunología , Humanos , Factor de Transcripción MafB/metabolismo , Monocitos/citología , Monocitos/inmunología
8.
Blood Cancer J ; 6(6): e439, 2016 06 24.
Artículo en Inglés | MEDLINE | ID: mdl-27341078

RESUMEN

microRNAs (miRNAs) are relevant in the pathogenesis of primary myelofibrosis (PMF) but our understanding is limited to specific target genes and the overall systemic scenario islacking. By both knowledge-based and ab initio approaches for comparative analysis of CD34+ cells of PMF patients and healthy controls, we identified the deregulated pathways involving miRNAs and genes and new transcriptional and post-transcriptional regulatory circuits in PMF cells. These converge in a unique and integrated cellular process, in which the role of specific miRNAs is to wire, co-regulate and allow a fine crosstalk between the involved processes. The PMF pathway includes Akt signaling, linked to Rho GTPases, CDC42, PLD2, PTEN crosstalk with the hypoxia response and Calcium-linked cellular processes connected to cyclic AMP signaling. Nested on the depicted transcriptional scenario, predicted circuits are reported, opening new hypotheses. Links between miRNAs (miR-106a-5p, miR-20b-5p, miR-20a-5p, miR-17-5p, miR-19b-3p and let-7d-5p) and key transcription factors (MYCN, ATF, CEBPA, REL, IRF and FOXJ2) and their common target genes tantalizingly suggest new path to approach the disease. The study provides a global overview of transcriptional and post-transcriptional deregulations in PMF, and, unifying consolidated and predicted data, could be helpful to identify new combinatorial therapeutic strategy. Interactive PMF network model: http://compgen.bio.unipd.it/pmf-net/.


Asunto(s)
MicroARNs/genética , Proteínas de Neoplasias/genética , Mielofibrosis Primaria/genética , Procesamiento Postranscripcional del ARN , Anciano , Anciano de 80 o más Años , Antígenos CD34/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Mielofibrosis Primaria/patología , Transducción de Señal , Transcripción Genética
9.
BMJ Open Sport Exerc Med ; 2(1): e000142, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28890800

RESUMEN

The nomenclature and the lack of consensus of clinical evaluation and imaging assessment in groin pain generate significant confusion in this field. The Groin Pain Syndrome Italian Consensus Conference has been organised in order to prepare a consensus document regarding taxonomy, clinical evaluation and imaging assessment for groin pain. A 1-day Consensus Conference was organised on 5 February 2016, in Milan (Italy). 41 Italian experts with different backgrounds participated in the discussion. A consensus document previously drafted was discussed, eventually modified, and finally approved by all members of the Consensus Conference. Unanimous consensus was reached concerning: (1) taxonomy (2) clinical evaluation and (3) imaging assessment. The synthesis of these 3 points is included in this paper. The Groin Pain Syndrome Italian Consensus Conference reached a consensus on three main points concerning the groin pain syndrome assessment, in an attempt to clarify this challenging medical problem.

10.
Cell Death Differ ; 22(12): 1906-21, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25857263

RESUMEN

The transcription factor MYB has a key role in hematopoietic progenitor cells (HPCs) lineage choice, by enhancing erythropoiesis at the expense of megakaryopoiesis. We previously demonstrated that MYB controls erythroid versus megakaryocyte lineage decision by transactivating KLF1 and LMO2 expression. To further unravel the molecular mechanisms through which MYB affects lineage fate decision, we performed the integrative analysis of miRNA and mRNA changes in MYB-silenced human primary CD34+ HPCs. Among the miRNAs with the highest number of predicted targets, we focused our studies on hsa-miR-486-3p by demonstrating that MYB controls miR-486-3p expression through the transactivation of its host gene, ankyrin-1 (ANK1) and that miR-486-3p affects HPCs commitment. Indeed, overexpression and knockdown experiments demonstrated that miR-486-3p supports the erythropoiesis while restraining the megakaryopoiesis. Of note, miR-486-3p also favors granulocyte differentiation while repressing the macrophage differentiation. To shed some light on the molecular mechanisms through which miR-486-3p affects HPCs lineage commitment, we profiled the gene expression changes upon miR-486-3p overexpression in CD34+ cells. Among the genes downregulated in miR-486-3p-overexpressing HPCs and computationally predicted to be miR-486-3p targets, we identified MAF as a miR-486-3p target by 3'UTR luciferase reporter assay. Noteworthy, MAF overexpression was able to partially reverse the effects of miR-486-3p overexpression on erythroid versus megakaryocyte lineage choice. Moreover, the MYB/MAF co-silencing constrained the skewing of erythroid versus megakaryocyte lineage commitment in MYB-silenced CD34+ cells, by restraining the expansion of megakaryocyte lineage while partially rescuing the impairment of erythropoiesis. Therefore, our data collectively demonstrate that MYB favors erythropoiesis and restrains megakaryopoiesis through the transactivation of miR-486-3p expression and the subsequent downregulation of MAF. As a whole, our study uncovers the MYB/miR-486-3p/MAF axis as a new mechanism underlying the MYB-driven control of erythroid versus megakaryocyte lineage fate decision.


Asunto(s)
MicroARNs/metabolismo , Proteínas Proto-Oncogénicas c-maf/metabolismo , Proteínas Proto-Oncogénicas c-myb/metabolismo , Regiones no Traducidas 3' , Ancirinas/genética , Ancirinas/metabolismo , Antígenos CD34/metabolismo , Diferenciación Celular , Linaje de la Célula , Células Cultivadas , Condrogénesis , Regulación hacia Abajo , Células Eritroides/citología , Células Eritroides/metabolismo , Genes Reporteros , Sitios Genéticos , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/metabolismo , Humanos , Megacariocitos/citología , Megacariocitos/metabolismo , MicroARNs/antagonistas & inhibidores , MicroARNs/genética , Oligonucleótidos Antisentido/metabolismo , Regiones Promotoras Genéticas , Proteínas Proto-Oncogénicas c-maf/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-maf/genética , Proteínas Proto-Oncogénicas c-myb/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-myb/genética , Interferencia de ARN
11.
FEBS Lett ; 495(1-2): 131-6, 2001 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-11322961

RESUMEN

Curcumin is a natural compound showing antiproliferative properties. Recent studies suggest that these properties might be due to its ability to induce apoptosis in tumor cells. As mitochondria play a pivotal role in the induction of the apoptotic process, we analyzed the effect of curcumin on mitochondrial function. Curcumin induced an increase in rat liver mitochondrial membrane permeability, resulting in swelling, loss of membrane potential and inhibition of ATP synthesis. These effects were mediated by the opening of the permeability transition pore. Curcumin pore induction involved the oxidation of membrane thiol functions and required the presence of low Ca(2+) concentrations. These data suggest that mitochondria might be a target by which curcumin induces apoptosis of tumor cells.


Asunto(s)
Curcumina/farmacología , Canales Iónicos , Proteínas de la Membrana/efectos de los fármacos , Proteínas de la Membrana/metabolismo , Compuestos de Sulfhidrilo/metabolismo , Animales , Antineoplásicos/farmacología , Calcio/metabolismo , Quelantes/farmacología , Relación Dosis-Respuesta a Droga , Membranas Intracelulares/efectos de los fármacos , Membranas Intracelulares/fisiología , Luz , Masculino , Potenciales de la Membrana/efectos de los fármacos , Potenciales de la Membrana/fisiología , Mitocondrias Hepáticas/metabolismo , Proteínas de Transporte de Membrana Mitocondrial , Poro de Transición de la Permeabilidad Mitocondrial , Dilatación Mitocondrial/efectos de los fármacos , Oxidación-Reducción/efectos de los fármacos , Consumo de Oxígeno/efectos de los fármacos , Ratas , Ratas Wistar , Especies Reactivas de Oxígeno/metabolismo , Dispersión de Radiación
12.
FEBS Lett ; 435(1): 25-8, 1998 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-9755852

RESUMEN

The importance of mitochondria is rising as a target in pathologic processes such as ischemia. We have investigated the effects of hydrocortisone, prednisolone, dexamethasone and triamcinolone on oxidative phosphorylation, Ca2+ fluxes, swelling and membrane potentials in isolated kidney mitochondria. The measurement of respiration state 3 showed a significant decrease in presence of glucocorticoids whereas the other respiration states were not modified. When mitochondria were uncoupled and either the complexes III and IV or the complex IV were stimulated, the O2 consumption was decreased by glucocorticoids. These results suggest the cytochrome c oxidase is a target of the glucocorticoid effect on the respiratory chain. Indeed, the other mitochondrial functions investigated were unchanged, ruling out a direct effect on Ca2+ fluxes or swelling. A regulation of cytochrome c oxidase activity by glucocorticoids will be of particular interest in pathology involving metabolic insult.


Asunto(s)
Complejo IV de Transporte de Electrones/efectos de los fármacos , Complejo IV de Transporte de Electrones/metabolismo , Glucocorticoides/farmacología , Riñón/enzimología , Mitocondrias/enzimología , Animales , Transporte Biológico/efectos de los fármacos , Calcio/metabolismo , Dexametasona/farmacología , Activación Enzimática/efectos de los fármacos , Hidrocortisona/farmacología , Riñón/efectos de los fármacos , Riñón/fisiología , Masculino , Potenciales de la Membrana/efectos de los fármacos , Mitocondrias/fisiología , Dilatación Mitocondrial/efectos de los fármacos , Consumo de Oxígeno/efectos de los fármacos , Prednisolona/farmacología , Ratas , Ratas Wistar , Triamcinolona/farmacología
13.
Free Radic Biol Med ; 25(1): 113-20, 1998 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-9655529

RESUMEN

Twenty-five compounds (trimetazidine derivatives and other compounds, mostly having a free phenolic group) were examined for their radical scavenging and antioxidant properties. Their reaction with DPPH (2,2-diphenyl-1-picrylhydrazyl) as a measure of radical scavenging capacity was assessed by two parameters, namely EC50 (the concentration of antioxidant decreasing DPPH by 50%), and log Z, a kinetic parameter proposed here and derived from initial second-order rate constants and antioxidant/DPPH ratios. Antioxidant activities were determined by the inhibition of lipid peroxidation and albumin oxidation. The most active compounds were derivatives having a trolox or hydroquinone moiety. Physicochemical and structural properties were determined by molecular modeling as lipophilicity (virtual log P calculations) and H-Surf (solvent-accessible surface of hydroxyl hydrogen) and by quantum mechanical calculations (deltaH(ox) = oxidation enthalpy; deltaH(abs) = enthalpy of hydrogen abstraction). QSAR models were derived to identify molecular mechanisms responsible for the reactivity toward the DPPH radical and for the inhibition of lipid peroxidation. A useful prediction of antioxidant capacity could be achieved from calculated molecular properties and the kinetic parameter developed here.


Asunto(s)
Antioxidantes/química , Modelos Químicos , Picratos , Trimetazidina/análogos & derivados , Trimetazidina/química , Bepridil/análogos & derivados , Bepridil/metabolismo , Compuestos de Bifenilo , Simulación por Computador , Cresoles/química , Depuradores de Radicales Libres/química , Radicales Libres/metabolismo , Hidroquinonas/química , Fenoles/química , Relación Estructura-Actividad , Vitamina E/química
14.
Neuropharmacology ; 44(5): 642-52, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12668050

RESUMEN

Epidemiological studies have reported that cigarette smoking may protect from neurodegenerative diseases such as Parkinson's disease. These protective effects are thought to be mediated by nicotine. Recent data showed that nicotine significantly decreases respiratory control ratio (RCR) and superoxide anion generation of brain mitochondria. Thus, we investigated nicotine effects on rat brain in two experimental models: first, an in vitro anoxia/reoxygenation experiment and secondly, an in vivo rotenone-induced Parkinson-like syndrome. Anoxia/reoxygenation impaired mitochondrial respiration by 43.68% whereas in the presence of nicotine, it was less impaired, by 31.1% at 10(-7) M. In rats chronically administered rotenone (3 mg/kg/day), we observed profound mitochondrial damage: the RCR decreased by 50.36% and the superoxide anion generation and the membrane anisotropy increased by 56.03 and 13.43%, respectively. All of these indications of mitochondrial damage were limited by chronic administration of nicotine. Nicotine developed mitochondrial effects in vivo and in vitro at very low concentration. All these results were in accordance with epidemiological studies, which report a protective effect of nicotine in neurodegenerative diseases. Thus, we propose that one effect of nicotine is to preserve mitochondrial functions of the rat central nervous system.


Asunto(s)
Encéfalo/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Nicotina/administración & dosificación , Animales , Encéfalo/metabolismo , Hipoxia de la Célula/efectos de los fármacos , Hipoxia de la Célula/fisiología , Relación Dosis-Respuesta a Droga , Masculino , Mitocondrias/metabolismo , Consumo de Oxígeno/efectos de los fármacos , Consumo de Oxígeno/fisiología , Ratas , Ratas Wistar
15.
Neuroscience ; 115(2): 415-24, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12421607

RESUMEN

The effects of dehydroepiandrosterone (DHEA), dehydroepiandrosterone-sulfate (DHEA-S), alpha-estradiol and beta-estradiol on the main functions of purified rat brain mitochondria were investigated in basal conditions and after being submitted to various stresses including anoxia-reoxygenation, uncoupling and apoptosis. In basal conditions, DHEA (1 microM) and alpha-estradiol (1 microM) inhibited the respiratory control ratio (RCR) from 3.1 to 2.3 (25%). After anoxia-reoxygenation, DHEA (1 microM) and alpha-estradiol (1 microM) reversed significantly (P<0.01) the RCR decrease from 1.4 to 2.0 (21.5%) by restoring the state 4. This effect was observed when DHEA was added either before anoxia or before reoxygenation and when alpha-estradiol was added before anoxia. The mitochondrial membranes damaged after the anoxia-reoxygenation were 70 and 50%, respectively, protected by DHEA and alpha-estradiol at 1 microM. They also limited by about 50%, the cytochrome c release induced by the anoxia-reoxygenation. The oxygen consumption of mitochondria in presence of NADH (130 microM) and cytochrome c (5 microM) was significantly inhibited by DHEA and alpha-estradiol with high EC(50) of 30 and 22 pM, respectively. At 1 microM, they also inhibited the 10 microM carbonyl cyanide m-chlorophenylhydrazone-induced uncoupling to about 35% whereas beta-estradiol only decreased it to 9%. Our results indicated that DHEA and alpha-estradiol partly preserved the mitochondrial functions altered by an anoxia-reoxygenation with a concentration-dependent effect. The mechanism involved was independent of the classical genomic effect of steroids, the antioxidant properties but implicated a direct action on the mitochondrial membranes.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Encéfalo/metabolismo , Proteínas Portadoras , Deshidroepiandrosterona/farmacología , Estradiol/farmacología , Mitocondrias/metabolismo , Adenosina Trifosfatasas/metabolismo , Animales , Apoptosis/efectos de los fármacos , Carbonil Cianuro m-Clorofenil Hidrazona/farmacología , Hipoxia de la Célula/efectos de los fármacos , Grupo Citocromo c/metabolismo , Transporte de Electrón/efectos de los fármacos , Transporte de Electrón/fisiología , Complejo I de Transporte de Electrón , Complejo II de Transporte de Electrones , Complejo III de Transporte de Electrones/metabolismo , Complejo IV de Transporte de Electrones/metabolismo , Radicales Libres/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Fluidez de la Membrana/efectos de los fármacos , Proteínas de la Membrana/metabolismo , Mitocondrias/efectos de los fármacos , ATPasas de Translocación de Protón Mitocondriales , Complejos Multienzimáticos/metabolismo , NADH NADPH Oxidorreductasas/metabolismo , Estrés Oxidativo/efectos de los fármacos , Oxidorreductasas/metabolismo , Oxígeno/farmacología , Consumo de Oxígeno/efectos de los fármacos , Ratas , Especies Reactivas de Oxígeno/metabolismo , Succinato Deshidrogenasa/metabolismo , Desacopladores/farmacología
16.
Clin Pharmacokinet ; 19(2): 147-59, 1990 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2199129

RESUMEN

Many diseases appear to lead to a decrease of drug plasma binding due either to hypoalbuminaemia or to a modification of albumin structure. In other diseases, the binding of a drug may increase due to elevated concentrations of alpha 1-acid glycoprotein or lipoproteins. However that may be, the free fraction of a drug may vary in different pathologies. But an increase or decrease of the drug free fraction does not automatically mean an increase or decrease of the free drug concentration. Whatever the drug, a variation in the volume of distribution more or less proportional to the variation in the plasma free fraction can be expected. With respect to the clearance, the problem is much more complex and depends on the hepatic extraction ratio of drug. If the extraction is related to the free fraction (fu) of drug, a variation in fu will lead to a variation in the total drug concentration but no variation in the free drug concentration and no change in the pharmacological effect. If the extraction of a drug is dependent on hepatic flow, a variation in fu will lead to a change in the free drug concentration (with no change in the total drug concentration) and hence changes in the pharmacological effect. The aim of this article is to review the literature concerning disease-induced variations in plasma protein levels during the past 10 years. Finally, possible implications for drug dosage regimens are discussed generally from examples studies in the literature.


Asunto(s)
Proteínas Sanguíneas/metabolismo , Enfermedad , Animales , Relación Dosis-Respuesta a Droga , Quimioterapia , Humanos
17.
Clin Pharmacokinet ; 19(3): 218-29, 1990 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2203581

RESUMEN

Part I of this article, which appeared in the previous issue of the Journal, discussed the implications of variations in plasma protein levels in a number of diseases: hepatic and renal disease, acute myocardial infarction, burns, cancer, diabetes mellitus, hyperlipidaemia and inflammatory diseases. In Part II the authors continue their review with a further range of disease states, and consider their import for drug dosages.


Asunto(s)
Proteínas Sanguíneas/metabolismo , Preparaciones Farmacéuticas/administración & dosificación , Animales , Humanos , Trastornos Nutricionales/metabolismo , Farmacocinética , Enfermedades de la Tiroides/metabolismo
18.
Biochem Pharmacol ; 31(5): 831-5, 1982 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-7082352

RESUMEN

The binding of two drugs, ticlopidine and PCR 2362, chemically related to thienopyridin, potent antiaggregant agents, was studied in vitro to serum and to the corresponding isolated proteins, HSA, alpha 1-AGP, VLDL, LDL and HDL, using equilibrium dialysis at pH 7.4 and 37 degrees. The binding of these drugs to HSA and lipoproteins was non-saturable. The binding capacity of the lipoproteins was much greater than that of HSA and appeared to be dependent on lipid content. The binding capacities of the apoproteins were less than 10% of that observed for the native lipoproteins suggesting that drug-lipoprotein binding involves drug solubilization in the lipid phase of lipoproteins rather than a classical binding to definite sites. However drug binding to alpha 1-AGP was saturable with n = 3 for both and K = 89,000 and 33,000 for ticlopidine and PCR 2362, respectively. At physiological concentration, alpha 1-AGP binding capacity represented 15% of total serum binding capacity which could double in pathological states, in which the level of this protein is increased.


Asunto(s)
Lipoproteínas/metabolismo , Orosomucoide/metabolismo , Agregación Plaquetaria/efectos de los fármacos , Albúmina Sérica/metabolismo , Tiofenos/metabolismo , Humanos , Unión Proteica , Ticlopidina
19.
Biochem Pharmacol ; 37(14): 2807-14, 1988 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-3395358

RESUMEN

This paper describes the protein binding of cefazolin to human serum and to human serum albumin (HSA) using equilibrium dialysis. The drug is exclusively bound to HSA with a moderate affinity, Ka = 16,600 +/- 1600 M-1, and one saturable binding site, n = 0.73 +/- 0.02. Moreover cefazolin shows a dose-dependent binding leading a possible increase of the free fraction (when its total concentration increases). This antibiotic is displaced by free fatty acids (FFA) and bilirubin. Cefazolin binding to human serum and human serum albumin (HSA) was studied in presence of acidic drugs. At low concentrations clofibric acid and phenylbutazone both exhibiting high affinity for HSA displace strongly cefazolin. Valproic and salicylic acids, sulfamethoxazole, cefoperazone which have approximately the same affinity as cefazolin, must be used at higher concentrations to displace this antibiotic. A particular phenomenon was observed with cefazolin on HSA when associated with furosemide. A low concentration (5-25 microM) of this drug induces a positive cooperativity of binding between cefazolin and HSA. But at a molar ratio of furosemide to albumin greater than one, such cooperative interaction disappears and a competitive inhibition of cefazolin binding occurs. For all drugs studied, a competitive inhibition was found except for tryptophan. Finally, it is concluded that cefazolin shares the warfarin binding site on HSA.


Asunto(s)
Bilirrubina/farmacología , Proteínas Sanguíneas/metabolismo , Cefazolina/metabolismo , Ácidos Grasos no Esterificados/farmacología , Furosemida/farmacología , Humanos , Técnicas In Vitro , Unión Proteica/efectos de los fármacos , Albúmina Sérica/metabolismo , Tolbutamida/farmacología , Warfarina/farmacología
20.
Biochem Pharmacol ; 47(2): 175-8, 1994 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-8304961

RESUMEN

The interaction of isoproterenol with beta-adrenoceptors has been investigated in astroglial and neuronal cells isolated from adult rat cerebral cortices. Using the non-selective beta-adrenergic antagonist (3H)CGP-12177 as a ligand, binding experiments revealed that both types of cells exhibit beta-adrenoceptors. However the analysis of the isoproterenol displacement curve indicated that only neuronal cells contained the high affinity conformational state of the beta-adrenoceptor.


Asunto(s)
Astrocitos/efectos de los fármacos , Isoproterenol/farmacología , Neuronas/efectos de los fármacos , Receptores Adrenérgicos beta/metabolismo , Animales , Astrocitos/metabolismo , Unión Competitiva , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/metabolismo , Guanilil Imidodifosfato/farmacología , Neuronas/metabolismo , Propanolaminas/antagonistas & inhibidores , Propanolaminas/farmacología , Conformación Proteica , Ratas , Ratas Wistar , Receptores Adrenérgicos beta/química
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