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1.
J Orthop Traumatol ; 18(4): 439-450, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28921307

RESUMO

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.


Assuntos
Parede Abdominal/cirurgia , Traumatismos em Atletas/fisiopatologia , Traumatismos em Atletas/cirurgia , Impacto Femoroacetabular/fisiopatologia , Virilha/cirurgia , Adulto , Traumatismos em Atletas/diagnóstico por imagem , Fenômenos Biomecânicos , Estudos Transversais , Feminino , Impacto Femoroacetabular/classificação , Impacto Femoroacetabular/diagnóstico por imagem , Impacto Femoroacetabular/etiologia , Hérnia Inguinal/cirurgia , Humanos , Laparoscopia , Masculino , Dor/etiologia , Dor/fisiopatologia , Método Simples-Cego , Telas Cirúrgicas , Síndrome , Adulto Jovem
2.
Circulation ; 124(8): 901-11, 1-7, 2011 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-21810660

RESUMO

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.


Assuntos
Reanimação Cardiopulmonar , Fluorocarbonos , Parada Cardíaca/terapia , Hipotermia Induzida/métodos , Traumatismo por Reperfusão/prevenção & controle , Animais , Modelos Animais de Doenças , Coração/fisiologia , Parada Cardíaca/mortalidade , Parada Cardíaca/fisiopatologia , Rim/fisiologia , Ventilação Líquida , Fígado/fisiologia , Pulmão/fisiologia , Fenômenos Fisiológicos do Sistema Nervoso , Coelhos , Traumatismo por Reperfusão/mortalidade , Traumatismo por Reperfusão/fisiopatologia , Fatores de Tempo , Fibrilação Ventricular/mortalidade , Fibrilação Ventricular/fisiopatologia , Fibrilação Ventricular/terapia
3.
Cell Death Differ ; 15(1): 123-33, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17932501

RESUMO

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.


Assuntos
Hepatócitos/citologia , Fígado/citologia , Células-Tronco Multipotentes/citologia , Animais , Animais Recém-Nascidos , Diferenciação Celular , Linhagem da Célula , Separação Celular , Células Cultivadas , Condrócitos/citologia , Perfilação da Expressão Gênica , Hepatócitos/metabolismo , Imunofenotipagem , Fígado/embriologia , Camundongos , Células-Tronco Multipotentes/metabolismo , Neurônios/citologia , Análise de Sequência com Séries de Oligonucleotídeos , Osteoblastos/citologia , Fenótipo
4.
Leukemia ; 32(2): 438-449, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28745329

RESUMO

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.


Assuntos
Medula Óssea/metabolismo , Medula Óssea/patologia , Fibrose/metabolismo , Fibrose/patologia , Osteopontina/metabolismo , Proteínas Proto-Oncogênicas c-maf/metabolismo , Antígenos CD34/metabolismo , Proliferação de Células/fisiologia , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/patologia , Humanos , Megacariócitos/metabolismo , Megacariócitos/patologia , Transtornos Mieloproliferativos/metabolismo , Transtornos Mieloproliferativos/patologia , Policitemia Vera/metabolismo , Policitemia Vera/patologia , Mielofibrose Primária/metabolismo , Mielofibrose Primária/patologia , Trombocitemia Essencial/metabolismo , Trombocitemia Essencial/patologia
5.
Cell Death Differ ; 13(10): 1686-96, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16456583

RESUMO

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.


Assuntos
Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Fator de Transcrição MafB/genética , Fator de Transcrição MafB/metabolismo , Monócitos/citologia , Monócitos/metabolismo , Antígenos CD34/metabolismo , Linhagem Celular , Ensaio de Unidades Formadoras de Colônias , DNA Complementar/genética , Sangue Fetal/citologia , Sangue Fetal/imunologia , Sangue Fetal/metabolismo , Perfilação da Expressão Gênica , Células-Tronco Hematopoéticas/imunologia , Humanos , Técnicas In Vitro , Recém-Nascido , Fator de Transcrição MafB/antagonistas & inibidores , Monócitos/imunologia , Mielopoese , Análise de Sequência com Séries de Oligonucleotídeos , RNA Interferente Pequeno/genética , Retroviridae/genética , Transdução Genética , Regulação para Cima
6.
Leukemia ; 20(10): 1751-8, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16932344

RESUMO

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.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Leucemia Mieloide/tratamento farmacológico , Leucemia Mieloide/genética , Tretinoína/farmacologia , Doença Aguda , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Análise por Conglomerados , Bases de Dados Factuais , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Humanos , Leucemia Mieloide/patologia , Metanálise como Assunto , Análise de Sequência com Séries de Oligonucleotídeos , Valor Preditivo dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Vitamina D/farmacologia , Vitaminas/farmacologia
7.
Cell Death Differ ; 12(12): 1588-600, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15947790

RESUMO

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.


Assuntos
Antígenos CD34/imunologia , Diferenciação Celular/fisiologia , Células-Tronco Hematopoéticas/fisiologia , Receptores de Lipopolissacarídeos/imunologia , RNA Mensageiro/metabolismo , Antígenos de Diferenciação/metabolismo , Linhagem da Célula , Células Cultivadas , Citometria de Fluxo , Granulócitos/citologia , Granulócitos/imunologia , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/imunologia , Humanos , Fator de Transcrição MafB/metabolismo , Monócitos/citologia , Monócitos/imunologia
8.
Blood Cancer J ; 6(6): e439, 2016 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-27341078

RESUMO

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/.


Assuntos
MicroRNAs/genética , Proteínas de Neoplasias/genética , Mielofibrose Primária/genética , Processamento Pós-Transcricional do RNA , Idoso , Idoso de 80 Anos ou mais , Antígenos CD34/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Mielofibrose Primária/patologia , Transdução de Sinais , Transcrição Gênica
9.
BMJ Open Sport Exerc Med ; 2(1): e000142, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28890800

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-25857263

RESUMO

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.


Assuntos
MicroRNAs/metabolismo , Proteínas Proto-Oncogênicas c-maf/metabolismo , Proteínas Proto-Oncogênicas c-myb/metabolismo , Regiões 3' não Traduzidas , Anquirinas/genética , Anquirinas/metabolismo , Antígenos CD34/metabolismo , Diferenciação Celular , Linhagem da Célula , Células Cultivadas , Condrogênese , Regulação para Baixo , Células Eritroides/citologia , Células Eritroides/metabolismo , Genes Reporter , Loci Gênicos , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Humanos , Megacariócitos/citologia , Megacariócitos/metabolismo , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Oligonucleotídeos Antissenso/metabolismo , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-maf/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-maf/genética , Proteínas Proto-Oncogênicas c-myb/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-myb/genética , Interferência de RNA
11.
FEBS Lett ; 495(1-2): 131-6, 2001 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-11322961

RESUMO

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.


Assuntos
Curcumina/farmacologia , Canais Iônicos , Proteínas de Membrana/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Compostos de Sulfidrila/metabolismo , Animais , Antineoplásicos/farmacologia , Cálcio/metabolismo , Quelantes/farmacologia , Relação Dose-Resposta a Droga , Membranas Intracelulares/efeitos dos fármacos , Membranas Intracelulares/fisiologia , Luz , Masculino , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Mitocôndrias Hepáticas/metabolismo , Proteínas de Transporte da Membrana Mitocondrial , Poro de Transição de Permeabilidade Mitocondrial , Dilatação Mitocondrial/efeitos dos fármacos , Oxirredução/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Espalhamento de Radiação
12.
FEBS Lett ; 435(1): 25-8, 1998 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-9755852

RESUMO

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.


Assuntos
Complexo IV da Cadeia de Transporte de Elétrons/efeitos dos fármacos , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Glucocorticoides/farmacologia , Rim/enzimologia , Mitocôndrias/enzimologia , Animais , Transporte Biológico/efeitos dos fármacos , Cálcio/metabolismo , Dexametasona/farmacologia , Ativação Enzimática/efeitos dos fármacos , Hidrocortisona/farmacologia , Rim/efeitos dos fármacos , Rim/fisiologia , Masculino , Potenciais da Membrana/efeitos dos fármacos , Mitocôndrias/fisiologia , Dilatação Mitocondrial/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Prednisolona/farmacologia , Ratos , Ratos Wistar , Triancinolona/farmacologia
13.
Free Radic Biol Med ; 25(1): 113-20, 1998 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-9655529

RESUMO

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.


Assuntos
Antioxidantes/química , Modelos Químicos , Picratos , Trimetazidina/análogos & derivados , Trimetazidina/química , Bepridil/análogos & derivados , Bepridil/metabolismo , Compostos de Bifenilo , Simulação por Computador , Cresóis/química , Sequestradores de Radicais Livres/química , Radicais Livres/metabolismo , Hidroquinonas/química , Fenóis/química , Relação Estrutura-Atividade , Vitamina E/química
14.
Neuropharmacology ; 44(5): 642-52, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12668050

RESUMO

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.


Assuntos
Encéfalo/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Nicotina/administração & dosagem , Animais , Encéfalo/metabolismo , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/fisiologia , Relação Dose-Resposta a Droga , Masculino , Mitocôndrias/metabolismo , Consumo de Oxigênio/efeitos dos fármacos , Consumo de Oxigênio/fisiologia , Ratos , Ratos Wistar
15.
Neuroscience ; 115(2): 415-24, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12421607

RESUMO

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.


Assuntos
Adjuvantes Imunológicos/farmacologia , Encéfalo/metabolismo , Proteínas de Transporte , Desidroepiandrosterona/farmacologia , Estradiol/farmacologia , Mitocôndrias/metabolismo , Adenosina Trifosfatases/metabolismo , Animais , Apoptose/efeitos dos fármacos , Carbonil Cianeto m-Clorofenil Hidrazona/farmacologia , Hipóxia Celular/efeitos dos fármacos , Grupo dos Citocromos c/metabolismo , Transporte de Elétrons/efeitos dos fármacos , Transporte de Elétrons/fisiologia , Complexo I de Transporte de Elétrons , Complexo II de Transporte de Elétrons , Complexo III da Cadeia de Transporte de Elétrons/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Radicais Livres/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fluidez de Membrana/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Mitocôndrias/efeitos dos fármacos , ATPases Mitocondriais Próton-Translocadoras , Complexos Multienzimáticos/metabolismo , NADH NADPH Oxirredutases/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Oxirredutases/metabolismo , Oxigênio/farmacologia , Consumo de Oxigênio/efeitos dos fármacos , Ratos , Espécies Reativas de Oxigênio/metabolismo , Succinato Desidrogenase/metabolismo , Desacopladores/farmacologia
16.
Clin Pharmacokinet ; 19(3): 218-29, 1990 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2203581

RESUMO

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.


Assuntos
Proteínas Sanguíneas/metabolismo , Preparações Farmacêuticas/administração & dosagem , Animais , Humanos , Distúrbios Nutricionais/metabolismo , Farmacocinética , Doenças da Glândula Tireoide/metabolismo
17.
Clin Pharmacokinet ; 19(2): 147-59, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2199129

RESUMO

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.


Assuntos
Proteínas Sanguíneas/metabolismo , Doença , Animais , Relação Dose-Resposta a Droga , Tratamento Farmacológico , Humanos
18.
Biochem Pharmacol ; 31(5): 831-5, 1982 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-7082352

RESUMO

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.


Assuntos
Lipoproteínas/metabolismo , Orosomucoide/metabolismo , Agregação Plaquetária/efeitos dos fármacos , Albumina Sérica/metabolismo , Tiofenos/metabolismo , Humanos , Ligação Proteica , Ticlopidina
19.
Biochem Pharmacol ; 44(6): 1067-72, 1992 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-1329757

RESUMO

The effects of several antidepressants, amitriptyline, citalopram, desipramine, fluoxetine, maprotiline, mianserin, nialamide, nomifensine, tranylcypromine and viloxazine, on the accumulation of cyclic AMP and inositol monophosphates were studied in rat cerebral cortical slices. The two enzymatic systems were stimulated either by adrenergic agonists or by forskolin. Cyclic AMP and inositol monophosphates (IPs) formed were determined by a double label method. In vitro all drugs, except inhibitors of monoamine oxidase, nialamide and tranylcypromine, inhibited alpha 1-agonist-mediated production but did not modify the cyclic AMP accumulation. Otherwise, chronic desipramine but not citalopram administration decreased the accumulation of cyclic AMP (-39%) elicited by beta-adrenoceptor agonists; no change was observed in inositol phosphate metabolism after administration of these two drugs. These data support previous investigations showing a decrease in cyclic AMP production after chronic treatment with norepinephrine uptake blockers but do not confirm the hypothesis of a modification of alpha 1-adrenoceptor-stimulated inositol phosphate metabolism.


Assuntos
Antidepressivos/farmacologia , Química Encefálica , Receptores Adrenérgicos/efeitos dos fármacos , Animais , Antidepressivos/administração & dosagem , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Citalopram/administração & dosagem , Citalopram/farmacologia , Colforsina/farmacologia , AMP Cíclico/análise , Desipramina/administração & dosagem , Desipramina/farmacologia , Interações Medicamentosas , Fosfatos de Inositol/análise , Norepinefrina/farmacologia , Ratos , Transdução de Sinais/efeitos dos fármacos
20.
Biochem Pharmacol ; 37(14): 2807-14, 1988 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-3395358

RESUMO

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.


Assuntos
Bilirrubina/farmacologia , Proteínas Sanguíneas/metabolismo , Cefazolina/metabolismo , Ácidos Graxos não Esterificados/farmacologia , Furosemida/farmacologia , Humanos , Técnicas In Vitro , Ligação Proteica/efeitos dos fármacos , Albumina Sérica/metabolismo , Tolbutamida/farmacologia , Varfarina/farmacologia
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