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1.
BMC Nurs ; 22(1): 192, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37286976

RESUMO

BACKGROUND: The World Health Organisation (WHO) calls on stakeholders to give Higher Education a key educational importance for the future of Europe. Within the content of the training programmes at university, sexuality emerges as a relevant topic in the nursing degree, to promote integral health from a holistic perspective. However, research on the presence of sexuality at the curricular level in Higher Education suggests that it is incomplete and underdeveloped. METHODS: This is a protocol for a long-term, multi-centre, exploratory, descriptive, and cross-sectional study with a quantitative and qualitative approach lasting two years. The research will be carried out in the educational community, including, on the one hand, students, and professors and health professionals of nursing programmes from five universities in different parts of the world (Portugal, Spain, Italy, and the United States), and on the other hand, women, young people, and immigrants from these communities. The study will have several target populations. Firstly, the target is nursing students, with whom the aim is to define their perspective on the sexuality content taught at the university, and their level of knowledge. Secondly university professors and health professionals, with whom we will check their perspective on sexuality in the classroom, as well as their level of knowledge in this field. And finally, we will work with the community (women, young people, and immigrants) to whom we will try to bring sexuality from a useful and enjoyable perspective. In order to measure these variables in the protocol, instruments such as questionnaires and semi-structured interviews will be used. During data collection, ethical principles will be guaranteed and informed consent will be requested from the participants. DISCUSSION: The results of the research will have a high curricular impact on the educational community, and will last over time, since the tools generated in the project will be included as part of nursing training programmes. In addition, participation in the project will improve health education for health professionals and at the community level on sexuality in both urban and rural populations.

2.
BMC Neurol ; 22(1): 293, 2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35931957

RESUMO

BACKGROUND: Chronic Inflammatory Demyelinating Polyradiculoneuropathy (CIDP), a rare disorder affecting young adults, causes gradual weakness of the limbs, areflexia and impaired sensory function. New CIDP phenotypes without pathogenic antibodies but with modified cell profiles have been described. Treatments include corticotherapy, intravenous immunoglobulins, and plasmapheresis but the latter's action mechanisms remain unclear. Plasmapheresis supposedly removes toxic agents like antibodies from plasma but it is uncertain whether it has an immune-modulating effect. Also, the refining mechanisms of the two main plasmapheresis techniques-single plasma exchange and double filtration plasmapheresis (DFPP) - are different and unclear. This study aims to compare the evolution of peripheral lymphocyte profiles in patients with CIDP according to their treatment (single centrifugation plasmapheresis or DFPP) to better grasp the action mechanisms of both techniques. METHOD: In this proof-of-concept, monocentric, prospective, Single-Case Experimental Design study, 5 patients are evaluated by alternating their treatment type (single plasma exchange or DFPP) for 6 courses of treatment after randomization to their first treatment type. Each course of treatment lasts 2-4 weeks. For single plasma exchange, 60 ml/kg plasma will be removed from the patient and replaced with albumin solutes, with a centrifugation method to avoid the immunological reaction caused by the membrane used with the filtration method. For DFPP, 60 ml/kg plasma will be removed from the patient with a plasma separator membrane, then processed via a fractionator membrane to remove molecules of a greater size than albumin before returning it to the patient. This technique requires no substitution solutes, only 20 g of albumin to replace what would normally be lost during a session. The primary outcome is the difference between the two plasmapheresis techniques in the variation of the TH1/TH17 ratio over the period D0H0-D0H3 and D0H0-D7. Secondary outcomes include the variation in lymphocyte subpopulations at each session and between therapeutic plasmapheresis techniques, the clinical evolution, tolerance and cost of treatments. DISCUSSION: Understanding the action mechanisms of single plasma exchange and DFPP will help us to offer the right treatment to each patient with CIPD according to efficacy, tolerance and cost. TRIAL REGISTRATION: ClinicalTrials.gov under the no. NCT04742374 and date of registration 10 December 2020.


Assuntos
Troca Plasmática , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica , Albuminas , Humanos , Linfócitos , Fenótipo , Plasmaferese/métodos , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/terapia , Estudo de Prova de Conceito , Estudos Prospectivos , Projetos de Pesquisa
3.
J Endod ; 50(2): 173-180, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38049083

RESUMO

INTRODUCTION: EDTA plays a crucial role in regenerative endodontic therapy (RET) because of its significant biological effects. However, EDTA is also recognized as the preferred anticoagulant for hematologic tests. Thus, this study aimed to assess the influence of different EDTA activation techniques on the morphology of blood clots after conditioning the root canal dentin. METHODS: Forty extracted human teeth were prepared to simulate immature teeth and divided into the following 5 groups: (1) saline solution (negative control), (2) EDTA 17% + saline solution (CNI), (3) CNI + ultrasonic activation, (4) CNI + Easy clean activation, and (5) CNI + XP-endo Finisher activation. After irrigation, the roots were cleaved, and the root canals were filled with human blood to clot formation. The morphology and density of erythrocytes, platelets, and the fibrin network were observed using a scanning electron microscope. The fibrin network density was classified using a 4-point scale. Data were analyzed using the Friedman test and the Kruskal-Wallis test with Bonferroni adjustment (α = 5%). RESULTS: All groups exhibited consistent blood clot morphology characterized by a high density of erythrocytes, platelets, and white blood cells throughout the entire length of the root canal. The negative control group showed statistically significant high scores of fibrin density compared with the CNI group in all root thirds (P < .05). However, there was no statistical difference in the scores for the fibrin network density between the groups irrigated with EDTA with and without activation (P > .05). CONCLUSIONS: EDTA may impair the fibrin network formation compared with the saline group. However, EDTA activation did not significantly change the effects on the blood clot in contact with the conditioned intraradicular dentin.


Assuntos
Endodontia Regenerativa , Camada de Esfregaço , Trombose , Humanos , Ácido Edético/farmacologia , Microscopia Eletrônica de Varredura , Solução Salina/farmacologia , Fibrina/farmacologia , Irrigantes do Canal Radicular/farmacologia , Cavidade Pulpar , Dentina , Preparo de Canal Radicular/métodos , Hipoclorito de Sódio/farmacologia
4.
Lipids Health Dis ; 12: 87, 2013 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-23764148

RESUMO

BACKGROUND: We have previously demonstrated that increased rates of superoxide generation by extra-mitochondrial enzymes induce the activation of the mitochondrial ATP-sensitive potassium channel (mitoK(ATP)) in the livers of hypertriglyceridemic (HTG) mice. The resulting mild uncoupling mediated by mitoK(ATP) protects mitochondria against oxidative damage. In this study, we investigate whether immune cells from HTG mice also present increased mitoK(ATP) activity and evaluate the influence of this trait on cell redox state and viability. METHODS: Oxygen consumption (Clark-type electrode), reactive oxygen species production (dihydroethidium and H2-DCF-DA probes) and cell death (annexin V, cytocrome c release and Trypan blue exclusion) were determined in spleen mononuclear cells. RESULTS: HTG mice mononuclear cells displayed increased mitoK(ATP) activity, as evidenced by higher resting respiration rates that were sensitive to mitoK(ATP) antagonists. Whole cell superoxide production and apoptosis rates were increased in HTG cells. Inhibition of mitoK(ATP) further increased the production of reactive oxygen species and apoptosis in these cells. Incubation with HTG serum induced apoptosis more strongly in WT cells than in HTG mononuclear cells. Cytochrome c release into the cytosol and caspase 8 activity were both increased in HTG cells, indicating that cell death signaling starts upstream of the mitochondria but does involve this organelle. Accordingly, a reduced number of blood circulating lymphocytes was found in HTG mice. CONCLUSIONS: These results demonstrate that spleen mononuclear cells from hyperlipidemic mice have more active mitoK(ATP) channels, which downregulate mitochondrial superoxide generation. The increased apoptosis rate observed in these cells is exacerbated by closing the mitoK(ATP) channels. Thus, mitoK(ATP) opening acts as a protective mechanism that reduces cell death induced by hyperlipidemia.


Assuntos
Hiperlipidemias/metabolismo , Mitocôndrias/metabolismo , Canais de Potássio/metabolismo , Superóxidos/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Apoptose/genética , Hiperlipidemias/genética , Hiperlipidemias/patologia , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/patologia , Camundongos , Mitocôndrias/patologia , Estresse Oxidativo , Consumo de Oxigênio , Espécies Reativas de Oxigênio/metabolismo , Baço/citologia
5.
Nitric Oxide ; 26(3): 174-81, 2012 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-22349020

RESUMO

Nitrosyl ruthenium complexes are promising NO donor agents with numerous advantages for the biologic applications of NO. We have characterized the NO release from the nitrosyl ruthenium complex [Ru(NO(2))(bpy)(2)(4-pic)](+) (I) and the reactive oxygen/nitrogen species (ROS/RNS)-mediated NO actions on isolated rat liver mitochondria. The results indicated that oxidation of mitochondrial NADH promotes NO release from (I) in a manner mediated by NO(2) formation (at neutral pH) as in mammalian cells, followed by an oxygen atom transfer mechanism (OAT). The NO released from (I) uncoupled mitochondria at low concentrations/incubation times and inhibited the respiratory chain at high concentrations/incubation times. In the presence of ROS generated by mitochondria NO gave rise to peroxynitrite, which, in turn, inhibited the respiratory chain and oxidized membrane protein-thiols to elicit a Ca(2+)-independent mitochondrial permeability transition; this process was only partially inhibited by cyclosporine-A, almost fully inhibited by the thiol reagent N-ethylmaleimide (NEM) and fully inhibited by the NO scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO). These actions correlated with the release of cytochrome c from isolated mitochondria as detected by Western blotting analysis. These events, typically involved in cell necrosis and/or apoptosis denote a potential specific action of (I) and analogs against tumor cells via mitochondria-mediated processes.


Assuntos
Complexos de Coordenação/farmacocinética , Mitocôndrias Hepáticas/metabolismo , NADP/metabolismo , Doadores de Óxido Nítrico/farmacocinética , Óxido Nítrico/farmacocinética , Rutênio/farmacocinética , Análise de Variância , Animais , Complexos de Coordenação/química , Complexos de Coordenação/metabolismo , Citocromos c/metabolismo , Concentração de Íons de Hidrogênio , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Óxido Nítrico/metabolismo , Doadores de Óxido Nítrico/metabolismo , Oxirredução , Ratos , Ratos Wistar , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Rutênio/química , Rutênio/metabolismo , Compostos de Sulfidrila
6.
Mol Cell Biochem ; 363(1-2): 65-74, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22143534

RESUMO

SET protein (I2PP2A) is an inhibitor of PP2A, which regulates the phosphorylated Akt (protein kinase B) levels. We assessed the effects of SET overexpression in HEK293T cells, both in the presence and the absence of mild oxidative stress induced by 50 µM tert-butyl hydroperoxide. Immunoblotting assays demonstrated that SET accumulated in HEK293T cells and increased the levels of phosphorylated Akt and PTEN; in addition, SET decreased glutathione antioxidant defense of cell and increased expression of genes encoding antioxidant defense proteins. Immunofluorescence analysis demonstrated that accumulated SET was equally distributed in cytoplasm and nucleus; however, in cells that had been exposed to oxidative stress, SET was found in large aggregates in the cytoplasm. SET accumulation in HEK293T cells correlated with inhibition of basal apoptosis as evidenced by a decrease in annexin V staining and activity of caspases; under mild oxidative stress, SET accumulation correlated with caspase-independent cell death, as evidenced by increased PI and annexin V/PI double staining. The results suggest that accumulated SET could act via Akt/PTEN either as cell survival signal or as oxidative stress sensor for cell death.


Assuntos
Núcleo Celular/metabolismo , Citoplasma/metabolismo , Chaperonas de Histonas/metabolismo , Estresse Oxidativo , Transdução de Sinais , Fatores de Transcrição/metabolismo , Apoptose , Western Blotting , Caspases/metabolismo , Núcleo Celular/efeitos dos fármacos , Sobrevivência Celular , Citoplasma/efeitos dos fármacos , Proteínas de Ligação a DNA , Imunofluorescência , Glutationa/metabolismo , Células HEK293 , Chaperonas de Histonas/genética , Humanos , Oxidantes/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , PTEN Fosfo-Hidrolase/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fatores de Tempo , Fatores de Transcrição/genética , Transfecção , Regulação para Cima , terc-Butil Hidroperóxido/farmacologia
7.
Clin Chem Lab Med ; 50(3): 441-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22505549

RESUMO

BACKGROUND: Variants in uptake and efflux transporters can influence diverse statin pharmacokinetics in different populations. This study aimed to investigate the influence of SLCO1B1 gene polymorphism on simvastatin treatment efficacy in a Brazilian population of European ancestry. METHODS: Two hundred and sixteen hypercholesterolemic patients were treated with 20 mg/day simvastatin for 6 months. Plasma lipid and lipoprotein levels were measured at baseline and after 2 and 6 months of treatment. The single nucleotide polymorphisms (SNPs) c.388A>G, c.463C>A and c.521T>C at SLCO1B1 gene were determined by allelic discrimination with TaqMan 5'-nuclease assays. The 388G allele was observed in 160 patients, the 521 C allele was observed in 64 individuals, whereas 61 subjects were 463 A allele carriers. RESULTS: Carriers of the SLCO1B1 388G allele had a greater reduction of total cholesterol and LDL cholesterol with simvastatin treatment, when compared with 56 388A homozygotes (-28.8% vs. -15.8%, p=0.005 and -39.0% vs. -30.6%, p=0.003; respectively). The c.463C>A and c.521T>C SNPs were not associated with simvastatin treatment. The SLCO1B1 haplotypes showed no statistically significant differences in mean percentage reductions in lipid and lipoprotein levels after simvastatin treatment. CONCLUSIONS: The present study suggests that the SLCO1B1 c.388A>G polymorphism could play a role in the inter-individual variation of clinical response to simvastatin in Brazilians. These results add to those that suggest that the effects of SLCO1B1 variants may be statin specific.


Assuntos
Anticolesterolemiantes/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Transportadores de Ânions Orgânicos/genética , Polimorfismo de Nucleotídeo Único , Sinvastatina/uso terapêutico , População Branca/genética , Anticolesterolemiantes/uso terapêutico , Brasil , Feminino , Frequência do Gene/genética , Haplótipos/genética , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Transportador 1 de Ânion Orgânico Específico do Fígado , Masculino , Pessoa de Meia-Idade , Sinvastatina/farmacologia , Resultado do Tratamento
8.
Toxicol Appl Pharmacol ; 253(3): 282-9, 2011 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-21549140

RESUMO

Guttiferone-A (GA) is a natural occurring polyisoprenylated benzophenone with cytotoxic action in vitro and anti-tumor action in rodent models. We addressed a potential involvement of mitochondria in GA toxicity (1-25 µM) toward cancer cells by employing both hepatic carcinoma (HepG2) cells and succinate-energized mitochondria, isolated from rat liver. In HepG2 cells GA decreased viability, dissipated mitochondrial membrane potential, depleted ATP and increased reactive oxygen species (ROS) levels. In isolated rat-liver mitochondria GA promoted membrane fluidity increase, cyclosporine A/EGTA-insensitive membrane permeabilization, uncoupling (membrane potential dissipation/state 4 respiration rate increase), Ca²âº efflux, ATP depletion, NAD(P)H depletion/oxidation and ROS levels increase. All effects in cells, except mitochondrial membrane potential dissipation, as well as NADPH depletion/oxidation and permeabilization in isolated mitochondria, were partly prevented by the a NAD(P)H regenerating substrate isocitrate. The results suggest the following sequence of events: 1) GA interaction with mitochondrial membrane promoting its permeabilization; 2) mitochondrial membrane potential dissipation; 3) NAD(P)H oxidation/depletion due to inability of membrane potential-sensitive NADP+ transhydrogenase of sustaining its reduced state; 4) ROS accumulation inside mitochondria and cells; 5) additional mitochondrial membrane permeabilization due to ROS; and 6) ATP depletion. These GA actions are potentially implicated in the well-documented anti-cancer property of GA/structure related compounds.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Benzofenonas/farmacologia , Membranas Mitocondriais/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Trifosfato de Adenosina/análise , Animais , Benzofenonas/farmacocinética , Cálcio/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Células Hep G2 , Humanos , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Membranas Mitocondriais/metabolismo , Dilatação Mitocondrial/efeitos dos fármacos , NAD/análise , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo
9.
Biochim Biophys Acta ; 1787(3): 176-82, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19161974

RESUMO

The oxidation of critical cysteines/related thiols of adenine nucleotide translocase (ANT) is believed to be an important event of the Ca(2+)-induced mitochondrial permeability transition (MPT), a process mediated by a cyclosporine A/ADP-sensitive permeability transition pores (PTP) opening. We addressed the ANT-Cys(56) relative mobility status resulting from the interaction of ANT/surrounding cardiolipins with Ca(2+) and/or ADP by means of computational chemistry analysis (Molecular Interaction Fields and Molecular Dynamics studies), supported by classic mitochondrial swelling assays. The following events were predicted: (i) Ca(2+) interacts preferentially with the ANT surrounding cardiolipins bound to the H4 helix of translocase, (ii) weakens the cardiolipins/ANT interactions and (iii) destabilizes the initial ANT-Cys(56) residue increasing its relative mobility. The binding of ADP that stabilizes the conformation "m" of ANT and/or cardiolipin, respectively to H5 and H4 helices, could stabilize their contacts with the short helix h56 that includes Cys(56), accounting for reducing its relative mobility. The results suggest that Ca(2+) binding to adenine nucleotide translocase (ANT)-surrounding cardiolipins in c-state of the translocase enhances (ANT)-Cys(56) relative mobility and that this may constitute a potential critical step of Ca(2+)-induced PTP opening.


Assuntos
Cálcio/metabolismo , Cardiolipinas/metabolismo , Cisteína/metabolismo , Mitocôndrias Hepáticas/efeitos dos fármacos , Translocases Mitocondriais de ADP e ATP/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/efeitos dos fármacos , Difosfato de Adenosina/metabolismo , Animais , Permeabilidade da Membrana Celular/efeitos dos fármacos , Simulação por Computador , Ciclosporina/farmacologia , Imunossupressores/farmacologia , Masculino , Mitocôndrias Hepáticas/metabolismo , Poro de Transição de Permeabilidade Mitocondrial , Dilatação Mitocondrial/efeitos dos fármacos , Modelos Químicos , Modelos Moleculares , Estresse Oxidativo , Conformação Proteica , Ratos , Ratos Wistar , Ácido Succínico/farmacologia
10.
J Bioenerg Biomembr ; 42(4): 329-35, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20614171

RESUMO

Mitochondrial membrane carriers containing proline and cysteine, such as adenine nucleotide translocase (ANT), are potential targets of cyclophilin D (CyP-D) and potential Ca(2+)-induced permeability transition pore (PTP) components or regulators; CyP-D, a mitochondrial peptidyl-prolyl cis-trans isomerase, is the probable target of the PTP inhibitor cyclosporine A (CsA). In the present study, the impact of proline isomerization (from trans to cis) on the mitochondrial membrane carriers containing proline and cysteine was addressed using ANT as model. For this purpose, two different approaches were used: (i) Molecular dynamic (MD) analysis of ANT-Cys(56) relative mobility and (ii) light scattering techniques employing rat liver isolated mitochondria to assess both Ca(2+)-induced ANT conformational change and mitochondrial swelling. ANT-Pro(61) isomerization increased ANT-Cys(56) relative mobility and, moreover, desensitized ANT to the prevention of this effect by ADP. In addition, Ca(2+) induced ANT "c" conformation and opened PTP; while the first effect was fully inhibited, the second was only attenuated by CsA or ADP. Atractyloside (ATR), in turn, stabilized Ca(2+)-induced ANT "c" conformation, rendering the ANT conformational change and PTP opening less sensitive to the inhibition by CsA or ADP. These results suggest that Ca(2+) induces the ANT "c" conformation, apparently associated with PTP opening, but requires the CyP-D peptidyl-prolyl cis-trans isomerase activity for sustaining both effects.


Assuntos
Cálcio/metabolismo , Cisteína/metabolismo , Translocases Mitocondriais de ADP e ATP/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Prolina/metabolismo , Difosfato de Adenosina/metabolismo , Difosfato de Adenosina/farmacologia , Animais , Cálcio/farmacologia , Humanos , Isomerismo , Masculino , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Membranas Mitocondriais/efeitos dos fármacos , Membranas Mitocondriais/metabolismo , Poro de Transição de Permeabilidade Mitocondrial , Dilatação Mitocondrial , Modelos Moleculares , Simulação de Dinâmica Molecular , Conformação Proteica , Ratos , Ratos Wistar , Relação Estrutura-Atividade
11.
Nitric Oxide ; 20(1): 24-30, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18950724

RESUMO

The ruthenium nitrosyl complex trans-[Ru(NO)(NH(3))(4)(py)](PF(6))(3) (pyNO), a nitric oxide (NO) donor, was studied in regard to the release of NO and its impact both on isolated mitochondria and HepG2 cells. In isolated mitochondria, NO release from pyNO was concomitant with NAD(P)H oxidation and, in the 25-100 microM range, it resulted in dissipation of mitochondrial membrane potential, inhibition of state 3 respiration, ATP depletion and reactive oxygen species (ROS) generation. In the presence of Ca(2+), mitochondrial permeability transition (MPT), an unspecific membrane permeabilization involved in cell necrosis and some types of apoptosis, was elicited. As demonstrated by externalization of phosphatidylserine and activation of caspase-9 and caspase-3, pyNO (50-100 microM) induced HepG2 cell death, mainly by apoptosis. The combined action of the NO itself, the peroxynitrite yielded by NO in the presence of reactive oxygen species (ROS) and the oxidative stress generated by the NAD(P)H oxidation is proposed to be involved in cell death by pyNO, both via respiratory chain inhibition and ROS levels increase, or even via MPT, if Ca(2+) is present.


Assuntos
Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Doadores de Óxido Nítrico/farmacologia , Óxido Nítrico/metabolismo , Compostos Organometálicos/farmacologia , Rutênio/farmacologia , Trifosfato de Adenosina/metabolismo , Análise de Variância , Animais , Apoptose/efeitos dos fármacos , Caspases/metabolismo , Linhagem Celular Tumoral , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Poro de Transição de Permeabilidade Mitocondrial , Dilatação Mitocondrial/efeitos dos fármacos , NADPH Oxidases/metabolismo , Oxirredução , Ratos , Espécies Reativas de Oxigênio/metabolismo
12.
Phytother Res ; 22(9): 1213-8, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18729257

RESUMO

Mitochondria are important intracellular sources and targets of reactive oxygen species (ROS), while flavonoids, a large group of secondary plant metabolites, are important antioxidants. Following our previous study on the energetics of mitochondria exposed to the flavonoids quercetin, taxifolin, catechin and galangin, the present work addressed the antioxidant activity of these compounds (1-50 micromol/L) on Fe(2+)/citrate-mediated membrane lipid peroxidation (LPO) in isolated rat liver mitochondria, running in parallel studies of their antioxidant activity in non-organelle systems. Only quercetin inhibited the respiratory chain of mitochondria and only galangin caused uncoupling. Quercetin and galangin were far more potent than taxifolin and catechin in affording protection against LPO (IC(50) = 1.23 +/- 0.27 and 2.39 +/- 0.79 micromol/L, respectively), although only quercetin was an effective scavenger of both 2,2-diphenyl-1-picrylhydrazyl (DPPH) and superoxide radicals. These results, together with the previous study, suggest that the 2,3-double bond in conjugation with the 4-oxo function in the flavonoid structure are major determinants of the antioxidant activity of flavonoids in mitochondria, the presence of an o-di-OH structure on the B-ring, as occurs in quercetin, favours this activity via superoxide scavenging, while the absence of this structural feature in galangin, favours it via a decrease in membrane fluidity and/or mitochondrial uncoupling.


Assuntos
Antioxidantes/farmacologia , Flavonoides/farmacologia , Mitocôndrias Hepáticas/efeitos dos fármacos , Animais , Transporte de Elétrons , Peroxidação de Lipídeos , Masculino , Potenciais da Membrana/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Ratos , Ratos Wistar
13.
Eur J Pharmacol ; 566(1-3): 43-9, 2007 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-17459371

RESUMO

We previously reported that the nonsteroidal anti-inflammatory drug, nimesulide (N-[4-nitro-2-phenoxyphenyl]-methanesulfonamide), is an uncoupler and oxidizes NAD(P)H in isolated rat liver mitochondria, triggering mitochondrial Ca2+ efflux or, if this effect is inhibited, eliciting mitochondrial permeability transition (Mingatto et al., Br. J. Pharmacol. 131:1154-1160, 2000). We presently demonstrated that nimesulide's hydroxylated metabolite (4-hydroxy nimesulide) lacks the uncoupling property of the parent drug, while keeping its ability to oxidize mitochondrial NADPH. In the presence of 10 microM Ca2+, low (5-50 microM) concentrations of 4-hydroxy nimesulide elicited mitochondrial permeability transition, as assessed by cyclosporin A-sensitive mitochondrial swelling, associated with mitochondrial Ca2+ efflux/membrane potential dissipation (Deltapsi), apparently occurring on account of the oxidation of mitochondrial protein thiols; no involvement of reactive oxygen species was observed. While nimesulide (0.5 or 1 mM, 30 h incubation) did not lead to significant HepG2 cell death, 4-hydroxy nimesulide caused a low extent (approximately 15%) of cell necrosis, partly prevented by cyclosporine A, suggesting the involvement of mitochondrial permeability transition. Both nimesulide and 4-hydroxy nimesulide caused NADPH oxidation and Deltapsi dissipation in HepG2 cells. Because such Deltapsi dissipation induced by the metabolite was almost completely inhibited by cyclosporine A, it probably results from the mitochondrial permeability transition. Therefore, mitochondrial permeability transition, in apparent association with NADPH oxidation, constitutes the most probable cause of HepG2 cell death elicited by 4-hydroxy nimesulide.


Assuntos
Mitocôndrias Hepáticas/efeitos dos fármacos , Sulfonamidas/farmacologia , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Glutationa/metabolismo , Dissulfeto de Glutationa/metabolismo , Humanos , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias Hepáticas/fisiologia , NADP/metabolismo , Oxirredução , Permeabilidade/efeitos dos fármacos , Ratos , Ratos Wistar , Compostos de Sulfidrila/metabolismo
14.
Toxicol In Vitro ; 21(5): 782-8, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17321102

RESUMO

Toluene and xylene are chemicals present in various laboratory and other industrial products. Their toxicity to the nervous system and to the liver has been well documented. In the present work, we have studied in vitro effects of toluene and xylene on the respiration of succinate-energized isolated rat liver mitochondria, membrane potential, Ca2+ release, reactive oxygen species (ROS), and ATP levels. Also Ca2+-dependent, cyclosporine A-sensitive mitochondrial swelling, an indicator of mitochondrial permeability transition (MPT), was studied. At 0.5-2.5 and 0.25-1mM concentrations respectively, toluene and xylene stimulated state 4 respiration in apparent association with mitochondrial membrane potential dissipation and Ca2+ release; these actions of both solvents are consistent with mitochondrial uncoupling. At higher concentrations (2.5 and 5mM, respectively) toluene and xylene also inhibited state 3 respiration. At 0.1-1mM concentrations, xylene elicited significant increase of ROS generation and partly Ca2+-dependent cyclosporine A-sensitive mitochondrial swelling. At 1 mM concentration, toluene or xylene caused depletions of mitochondrial ATP, amounting to 66.3% and 40.3%, respectively; depletions were only slightly dependent on Ca2+. It was concluded that mitochondrial uncoupling via ATP depletion might be responsible for the cell toxicity of toluene described earlier and in particular, of xylene. In the case of xylene, mitochondrial ROS generation and MPT also appear to be involved.


Assuntos
Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Solventes/toxicidade , Tolueno/toxicidade , Desacopladores/toxicidade , Xilenos/toxicidade , Trifosfato de Adenosina/metabolismo , Animais , Cálcio/metabolismo , Técnicas In Vitro , Masculino , Potenciais da Membrana/efeitos dos fármacos , Organelas/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo
15.
Arq Neuropsiquiatr ; 64(2B): 507-10, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16917628

RESUMO

For twelve years, the subject of this report, a 38-year-old man, presented a clinical condition compatible with the SUNCT (short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing) syndrome. He presented a stabbing and intense daily pain located in the left pre-auricular and temporal regions. Each of these intense pain attacks lasted around one minute and presented a frequency of two to eight times per day. The pain was associated with ipsilateral lacrimation, conjunctival injection and rhinorrhea. MRI revealed a pituitary tumor with little suprasellar extent. The subjects serial assays of prolactin, GH, TSH and ACTH were within normal levels. Following transsphenoidal hypophysectomy, with complete removal of the tumor, the subject no more presented pain. The pathological diagnosis was non-secreting adenoma. Fourteen months after the surgery, he remains symptom-free.


Assuntos
Adenoma/complicações , Neoplasias Hipofisárias/complicações , Síndrome SUNCT/etiologia , Adenoma/diagnóstico , Adenoma/cirurgia , Adulto , Humanos , Hipofisectomia , Imageamento por Ressonância Magnética , Masculino , Neoplasias Hipofisárias/diagnóstico , Neoplasias Hipofisárias/cirurgia , Resultado do Tratamento
16.
Clin Pharmacol Ther ; 78(5): 551-8, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16321621

RESUMO

OBJECTIVE: Our objective was to investigate the interactions between common polymorphisms in ABCB1, CYP3A4, and CYP3A5 genes and the lipid-lowering efficacy and safety of the 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitor simvastatin. METHODS: One hundred sixteen hypercholesterolemic patients were prospectively screened by physical examination, medical history, and clinical laboratory evaluation and were included in this study. Subjects entering the study were treated with 20 mg/d simvastatin. Plasma lipid and lipoprotein levels were measured before treatment, after 2 months of treatment, and after 6 months of treatment. Ninety-nine patients completed the 6-month follow-up and were included in the association analysis for treatment efficacy. Seventeen subjects who had adverse drug reactions (ADRs) to simvastatin (ADR group) could not complete the 6-month follow-up and were included in the association analyses for safety. Myalgia was observed in 15 of 17 subjects and was the only ADR included in the association analyses, but other common ADRs were also observed. Myalgia was defined as proximal or diffuse muscle pain, tenderness, or weakness, or both pain and weakness, with normal or slightly increased serum creatine phosphokinase levels. ABCB1 (1236C>T, 2677G>A/T, and 3435C>T), CYP3A4 (-392A>G), and CYP3A5 (6986A>G) allele variants were determined by polymerase chain reaction and restriction mapping. RESULTS: After adjustment for covariates, carriers of the ABCB1 1236T variant allele had a greater reduction in total cholesterol and low-density lipoprotein cholesterol with simvastatin treatment, as compared with homozygotes with the wild-type allele (-29.0% [95% confidence interval (CI), -25.9 to -32.5] versus -24.2% [95% CI, -19.0 to -29.3] [P = .042] and -39.6% [95% CI, -35.8 to -44.0] versus -33.8% [95% CI, -27.4 to -40.2] [P = .042], respectively). Similar results were observed for the 2677G>A/T polymorphism and haplotype data. The 1236T, 2677non-G, and 3435T alleles were less frequent in ADR cases than in the non-ADR group (P < .05 for all single-nucleotide polymorphisms). Haplotype analyses also demonstrated a reduction of the T-non-G-T haplotype frequency (20%) in patients in whom myalgia developed during simvastatin treatment, as compared with the non-ADR group (41.4%) (P = .03). No significant associations were observed between the CYP3A4 -392A>G and CYP3A5*3 allele variants and the efficacy or tolerability of simvastatin. CONCLUSIONS: Our data suggest an association of ABCB1 gene polymorphisms and the efficacy and safety of simvastatin.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Sistema Enzimático do Citocromo P-450/genética , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Lipídeos/sangue , Sinvastatina/efeitos adversos , Sinvastatina/uso terapêutico , Transportador 1 de Cassete de Ligação de ATP , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Citocromo P-450 CYP3A , DNA/genética , Feminino , Variação Genética , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Estudos Prospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
Clin Chim Acta ; 362(1-2): 182-8, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16038892

RESUMO

BACKGROUND: In recent years, one of the focuses of genetic investigation in cardiology has been to identify the genetic factors associated with variable response to statin treatment. Polymorphisms in apolipoprotein E (APOE), cholesteryl ester transfer protein (CETP) and hepatic lipase (LIPC), proteins with major roles in lipid metabolism and homeostasis have been shown associated with lipid-lowering drugs response. METHODS: One hundred forty-six hypercholesterolemic patients of European descent were prospectively enrolled and treated with simvastatin 20 mg per day for over 6 months. Ninety-nine subjects completed the 6-month follow-up. Plasma lipids and lipoproteins were measured before and throughout the study. APOE (E*2, E*3 and E*4), LIPC-250A > G and CETP TaqIB genotypes were determined by PCR and restriction mapping. RESULTS: After a 6-month follow-up, no differences among genotypes in the percentage variation in lipid and lipoprotein concentrations for APOE and LIPC SNPs were observed. After adjustment for covariates, CETP B2B2 homozygotes showed a greater HDL-cholesterol increase compared to B1B2 and B1B1 subjects (14.1% vs. 1.7% and 1.3%, P < 0.05, respectively). CONCLUSION: Our study demonstrates that individual plasma HDL-cholesterol response to simvastatin is mediated, in part, by the CETP gene locus, with the B2 homozygotes having more benefit in HDL-C improvement than carriers of B1 allele.


Assuntos
Apolipoproteínas E/genética , Proteínas de Transporte/genética , Glicoproteínas/genética , Lipase/genética , Sinvastatina/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil , Proteínas de Transferência de Ésteres de Colesterol , Feminino , Humanos , Hipercolesterolemia/sangue , Hipercolesterolemia/tratamento farmacológico , Lipase/metabolismo , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Farmacogenética
18.
Braz J Biol ; 75(4 Suppl 1): S169-75, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26602336

RESUMO

Enchytraeids are small oligochaetes found worldwide in soils with sufficient moisture and organic matter, but scarcely studied in the Southern hemisphere. This is the third study on enchytraeid abundance in Brazil using wet extraction and the first carried out in Araucaria Mixed Forest (subtropical region). The sampling and extraction were based on the standard method ISO 23611-3/2007 using an adapted split soil corer and wet extraction with and without heat to assess the abundance of enchytraeids in a forest fragment at Embrapa Forestry in Colombo, Paraná State. The samplings were performed in 3 occasions between September 2011 and April 2012. The average numbers estimated by each method varied from appr. 2.000-12.000 (cold) and 5.000-12.000 ind./ m2 (hot), respectively, with a maximum of 44.000 ind./ m2 in one of the samples, the highest value reported so far in Brazil. The hot extraction was more advantageous, given the speed and preservation of the specimens in vivo, allowing taxonomic identification. Advantages and disadvantages of wet extractions compared to handsorting and formol methods are also discussed. Guaranidrilus, Hemienchytraeus, Enchytraeus, Fridericia and Achaeta were the genera identified in the samples.


Assuntos
Biodiversidade , Ecologia/métodos , Oligoquetos/fisiologia , Animais , Brasil , Florestas , Densidade Demográfica , Temperatura
19.
Arq. bras. med. vet. zootec. (Online) ; 71(6): 1917-1921, Nov.-Dec. 2019. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1055124

RESUMO

Paratuberculosis is a chronic and incurable disease that affects ruminants and other domestic animals. It is caused by Mycobacterium avium subsp. paratuberculosis (MAP) that may also be involved in some human diseases such as Crohn's disease, type 1 diabetes, sarcoidosis, multiple sclerosis, and Hashimoto's thyroiditis. The objective of this study was to investigate the occurrence of MAP DNA in samples of artisanal coalho cheese purchased in the State of Pernambuco. Forty samples of coalho cheese submitted to the Real Time Polymerase Chain Reaction (qPCR) technique were analyzed for the detection of the MAP region IS900. 11 (27.5%) were positive with a mean of 195.9 MAP colony forming unit (CFU) per gram of each sample, with a minimum of 30.3 CFU/g and a maximum of 324.2 CFU/g. Thus, this type of cheese that is one of the most consumed in this region of Brazil constitutes a source of human exposure to MAP. Further research in this area should be performed to evaluate the viability of the bacteria in this cheese type.(AU)


Paratuberculose é uma enfermidade crônica e incurável que acomete ruminantes e outras espécies de animais domésticos. É causada pelo Mycobacterium avium subsp. paratuberculosis (MAP) e ainda há a suspeita do seu envolvimento em enfermidades nos humanos como a doença de Crohn, diabetes tipo 1, sarcoidose, esclerose múltipla e tireoidite de Hashimoto. Objetivou-se com esta pesquisa investigar a ocorrência do DNA de MAP em amostras de queijo coalho artesanal adquiridas em estabelecimentos comerciais do Estado de Pernambuco. 40 amostras de queijo coalho artesanal foram submetidas a técnica de Reação em Cadeia da Polimerase em Tempo Real (qPCR) para detecção da região IS900 do MAP. 11 (27,5%) foram positivas com uma média de 195,9 unidades formadoras de colônia (UFC) de MAP por grama de queijo, com detecção mínima de 30,3UFC/g e máxima de 324,2UFC/g. Sendo assim, esse tipo de queijo que é um dos mais consumidos nesta região do Brasil constitui uma fonte de exposição humana ao MAP. Mais pesquisas nessa área devem ser realizadas para avaliar a viabilidade dessa bactéria no queijo coalho.(AU)


Assuntos
Paratuberculose , Queijo/microbiologia , Mycobacterium avium subsp. paratuberculosis/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real
20.
Arq Bras Cardiol ; 101(2): 127-33, 2013 Aug.
Artigo em Inglês, Português | MEDLINE | ID: mdl-23877745

RESUMO

BACKGROUND: No local studies evaluating the knowledge of cardiologists on the management of atrial fibrillation (AF) and their adherence to these guidelines are available. OBJECTIVE: To evaluate the knowledge of cardiologists on the guidelines and clinical practices for the treatment of AF, correlating it to the time since medical graduation. METHODS: Cross-sectional study randomly including cardiologists affiliated to the Society of Cardiology of the State of Rio Grande do Sul (Sociedade de Cardiologia do Estado do Rio Grande do Sul - SOCERGS). The physicians were divided into two groups, according to time since graduation: those graduated for more (G1) or less (G2) than 25 years. RESULTS: Of the 859 SOCERGS members, 150 were interviewed, and six refused to participate in the study. G1 comprised 71 physicians, and G2, 73. Differences were observed in regard to the following variables: use of betablockers as the first-choice drug for the control of AF response in 59.2% (G1) vs 91.8% (G2) (p<0.0001); use of digoxin as the preferred drug for the control of AF response in 19.7% (G1) vs 0% (G2) (p< 0.0001); warfarin as the preferred anticoagulant in 71.8% (G1) vs 93.2% (G2) (p=0.009); application of a risk score for anticoagulation in 73.2% (G1) vs 87.7% (G2) (p=0.02). In questions regarding the knowledge about the Brazilian Society of Cardiology's guideline for AF, the overall percentage of right answers was 82.3%. CONCLUSION: Most of the clinical measures regarding the management of AF comply with the guidelines, and the clinical practice differs according with the time since graduation.


Assuntos
Fibrilação Atrial/terapia , Cardiologia/normas , Competência Clínica/normas , Fidelidade a Diretrizes/estatística & dados numéricos , Guias de Prática Clínica como Assunto , Adulto , Brasil , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Padrões de Prática Médica , Sociedades Médicas , Inquéritos e Questionários , Fatores de Tempo
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