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1.
Actas dermo-sifiliogr. (Ed. impr.) ; 107(3): 215-223, abr. 2016. tab, ilus
Artigo em Inglês | IBECS | ID: ibc-150831

RESUMO

BACKGROUND: Among the different approaches for improving the effectiveness in the treatment of Capillary Malformations type Port Wine Stain (CM type PWS) are the intense pulsed light sources. There are few clinical studies prove useful in the treatment of CM. Furthermore, no studies have been published yet demonstrating the histological effects of IPL in CM. OBJECTIVES: To assess the histological effects of pulsed light in capillary malformations type port wine stain. We wanted to compare epidermal, dermal and vessel wall damage after treatment with different combinations of IPL parameters. MATERIAL AND METHODS: Fifty-five post-treatment biopsies were performed in 15 consenting patients with CM and stained with nitroblue-tetrazolium chloride (NBTC). Patients had not been treated previously. RESULTS: Fifteen patients with CM, with a median age of 39 years-old were enrolled in this study. In this series, the patients with the most severe epidermal damage were those with a darker phototype. Pink CM were especially resistant to treatment, even using high fluences, short pulse durations and stacking pulses. Longer intra- and interpulse delays were effective in purple CM, achieving adequate vessel destruction. CONCLUSIONS: IPL devices provide a vast amount of treatment possibilities and further studies are necessary to optimize therapeutic approaches to CM. In this study we have observed the histological effects of different pulses on the MC type PWS


ANTECEDENTES: Entre las distintas estrategias para intentar mejorar la eficacia en el tratamiento de las malformaciones capilares tipo mancha en vino de Oporto (MC tipo MVO) están las fuentes de luz pulsada intensa. Existen hasta la fecha pocos estudios clínicos que avalen su utilidad en el tratamiento de las MC. Además, no disponemos de estudios histológicos que objetiven los efectos de la luz pulsada en la coagulación de estos vasos anómalos. OBJETIVOS: Evaluar los efectos histológicos de la luz pulsada en las MC tipo MVO. Intentamos comparar el daño epidérmico, dérmico y de la pared de los vasos después del tratamiento con distintos parámetros de IPL. MATERIAL Y MÉTODOS: Fueron realizadas 55 biopsias postratamiento en las MC de 15 pacientes. Las muestras fueron teñidas con cloruro de nitroblue tetrazolium. RESULTADOS: Quince pacientes (edad media: 39 años) fueron inscritos en este estudio. En esta serie los pacientes con mayor daño epidérmico fueron aquellos con un fototipo más alto (>IV). Las malformaciones de color rosa pálido eran especialmente resistentes al tratamiento, incluso con altas fluencias, duraciones de pulso corto y pulsos repetidos. Los pulsos de una mayor duración fueron especialmente eficaces en malformaciones capilares violáceas. CONCLUSIONES: Los equipos de IPL ofrecen una gran cantidad de opciones de tratamiento en las MC, sin embargo necesitamos conocer mejor sus efectos para realizar abordajes más eficaces y seguros. En este estudio hemos podido observar los efectos histológicos de los distintos pulsos sobre las MC tipo MVO


Assuntos
Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Doenças do Cabelo/diagnóstico , Doenças do Cabelo/prevenção & controle , Doenças do Cabelo/terapia , Terapia de Luz Pulsada Intensa/efeitos adversos , Terapia de Luz Pulsada Intensa , Terapia de Luz Pulsada Intensa/instrumentação , Nitroazul de Tetrazólio/farmacologia , Nitroazul de Tetrazólio/uso terapêutico , Radiação Solar/efeitos adversos , Inativação Luminosa Assistida por Cromóforo/instrumentação , Inativação Luminosa Assistida por Cromóforo/métodos , Inativação Luminosa Assistida por Cromóforo
2.
Prep Biochem Biotechnol ; 44(7): 663-79, 2014 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-24279794

RESUMO

Proteins from the fresh roots of Stemona tuberosa (Stemonaceae) were extracted into 20 mM phosphate buffer, pH 7.2/0.1 M NaCl, precipitated with 90% saturation ammonium sulfate, and enriched by diethylaminoethanol (DEAE) cellulose. The protein eluted as a single main peak from the unbound fractions (ST-1), and appeared as a single band with superoxide dismutase (SOD) activity after native polyacrylamide gel electrophoresis (PAGE) resolution and zymogram development. ST-1 was classified as SOD due to its strong inhibition by HCN and H2O2. The amino acid sequence of three tryptic peptides of ST-1 matched with the SOD isozymes from Ananas comosus and Solanum lycopersicum. The SOD consisted of at least two heterologous protein subunits with molecular mass of 17.6 and 31.5 kD, respectively, and had an optimal SOD activity at pH 5 and over a temperature range of 0-50°C. MgCl2, MnCl2, and HgCl2 were strongly inhibitory at all concentrations tested. The SOD activity was completely negated in the presence of 0.5 mM SDS or 5 mM HgCl2. The relationship between riboflavin and nitroblue tetrazolium (NBT) on SOD activity was linear, giving K m and V max values of the purified SOD of 62.414 ± 0.015 M and 101.010 ± 0.022 µmol/min/mg protein for NBT and 27.389 ± 0.032 M and 38.167 ± 0.021 µmol/min/mg protein for riboflavin, respectively.


Assuntos
Stemonaceae/enzimologia , Superóxido Dismutase/isolamento & purificação , Superóxido Dismutase/metabolismo , Proliferação de Células/efeitos dos fármacos , Eletroforese em Gel de Poliacrilamida , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Metais/farmacologia , Peso Molecular , Nitroazul de Tetrazólio/farmacologia , Proteínas de Plantas/isolamento & purificação , Raízes de Plantas/enzimologia , Riboflavina/farmacologia , Superóxido Dismutase/química , Espectrometria de Massas em Tandem , Temperatura
3.
PLoS One ; 7(7): e41081, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22815923

RESUMO

Reintroductions are an increasingly common conservation restoration tool; however, little attention has hitherto been given to different methods for monitoring the stress encountered by reintroduced individuals. We compared ten potential measures of stress within four different categories (neuroendocrine, cell function, body condition and immune system function) as proxies for animal welfare in water voles being reintroduced to the Upper Thames region, Oxfordshire, UK. Captive-bred voles were assessed pre-release, and each month post-release for up to five months. Wild-born voles were captured in the field and assessed from two months post-release. Plasma corticosteroid, hydration and body condition of captive-bred voles differed between their pre-release measures and both their first ("short-term") recapture, and their final recapture ("long-term" release), however only body condition and immunocompetence measured using the Nitroblue Tetrazolium (NBT) test were significantly different post-release between the first and last recaptures. Captive-bred animals had lower fat reserves, higher weight/length ratios and better immunocompetence (NBT) than did wild-born voles. Captive-bred males had higher ectoparasite burdens compared to wild-born males and, as reintroduction site quality decreased, became less hydrated. These observations indicate that some methods can identify changes in the stress response in individuals, highlighting areas of risk in a reintroduction programme. In addition, a single measure may not provide a full picture of the stress experienced; instead, a combination of measures of different physiological systems may give a more complete indication of stress during the reintroduction process. We highlight the need to monitor stress in reintroductions using measures from different physiological systems to inform on possible animal welfare improvements and thus the overall success rate of reintroductions.


Assuntos
Bem-Estar do Animal , Arvicolinae/fisiologia , Conservação dos Recursos Naturais/métodos , Extinção Biológica , Tecido Adiposo , Corticosteroides/metabolismo , Animais , Cruzamento , Sistema Endócrino/fisiopatologia , Meio Ambiente , Feminino , Sistema Imunitário/fisiopatologia , Masculino , Modelos Estatísticos , Nitroazul de Tetrazólio/farmacologia , Dinâmica Populacional , Refratometria , Água
4.
Vet Parasitol ; 172(1-2): 135-8, 2010 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-20483539

RESUMO

The nitroblue tetrazolium reduction test (NBT) is a quick, easy and cheap assay based on the activation percentage of neutrophils in peripheral blood. The aim of this study was to evaluate the NBT on healthy dogs and in dogs affected by different degrees of leishmaniasis (Stages I and IV). Forty healthy dogs, 20 dogs in Stage I and 20 dogs in Stage IV were included in the study. Three millilitres of blood were extracted from all the dogs via jugular venipuncture in tubes with EDTA. Incubation with NBT was performed depositing 0.05 ml of the leukocyte suspension in the same quantity of 0.1% concentration NBT. The results of the test were reported as NBT reduction rate which represents the percentage of the total of neutrophils evaluated that presented cytoplasmatic accumulations of formazan, meaning a positive NBT reduction. The mean NBT reduction rate for the healthy dogs group was 4.57%, 34% for Stage I dogs (mild disease) and 3.7% for dogs in Stage IV (severe disease), showing that dogs affected with leishmaniasis but with no clinical development of disease have a significantly higher neutrophil reactivity (p<0.01). Although more studies evaluating the correlation of NBT with other tests prior to and during treatment are needed, NBT could be a good assay in canine leishmaniasis evaluation.


Assuntos
Doenças do Cão/parasitologia , Leishmania/isolamento & purificação , Leishmaniose/veterinária , Nitroazul de Tetrazólio/farmacologia , Animais , Doenças do Cão/sangue , Doenças do Cão/imunologia , Cães , Feminino , Leishmania/imunologia , Leishmaniose/sangue , Leishmaniose/imunologia , Leishmaniose/parasitologia , Masculino , Ativação de Neutrófilo/imunologia
5.
Tuberk Biolezni Legkih ; (5): 45-51, 2010.
Artigo em Russo | MEDLINE | ID: mdl-27534041

RESUMO

Examination of 270 children and 74 adolescents by the currently available studies using the NBT test with specific antigens (BCG and tuberculin) could first diagnose the circumscribed forms of pulmonary and extrapulmonary tuberculosis in 6.7%. There was evidence for the persistent activity of inflammation in the presence of calcifications in 39 (11.3%) of the pretreated tuberculosis patients. The diagnosis in all the patients was associated with a positive NBT test. The latter could define indications for chemoprophylaxis of tuberculosis in 109 (31.7%) subjects, rule out a need for drugs in this period in 109 (31.7%) patients, and establish no need for phthisiatricians to follow up 135 (39.2) patients. NBT test was shown to be a tool to confirm or exclude the activity of tuberculosis infection in children and adolescents.


Assuntos
Nitroazul de Tetrazólio/farmacologia , Teste Tuberculínico/métodos , Tuberculose/diagnóstico , Adolescente , Quimioprevenção/métodos , Criança , Diagnóstico Diferencial , Feminino , Humanos , Indicadores e Reagentes/farmacologia , Masculino , Seleção de Pacientes , Reprodutibilidade dos Testes , Tuberculose/prevenção & controle , Tuberculose/terapia
7.
Am J Physiol Heart Circ Physiol ; 293(4): H2085-92, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17644566

RESUMO

Tempol catalyzes the formation of H(2)O(2) from superoxide and relaxes blood vessels. We tested the hypothesis that the generation of H(2)O(2) by tempol in vascular smooth muscle cells during oxidative stress contributes to the vasorelaxation. Tempol and nitroblue tetrazolium (NBT) both metabolize superoxide in vascular smooth muscle cells, but only tempol generates H(2)O(2). Rat pressurized mesenteric arteries were exposed for 20 min to the thromboxane-prostanoid receptor agonist, U-46619, or norepinephrine. During U-46619, tempol caused a transient dilation (22 +/- 2%), whereas NBT was ineffective (2 +/- 1%), and neither dilated vessels constricted with norepinephrine, which does not cause vascular oxidative stress. Neither endothelium removal nor blockade of K(+) channels with 40 mM KCl affected the tempol-induced dilation, but catalase blunted the tempol dilation by 53 +/- 7%. Tempol, but not NBT, increased H(2)O(2) in rat mesenteric vessels detected with dichlorofluorescein. To test physiological relevance in vivo, topical application of tempol caused a transient dilation (184 +/- 20%) of mouse cremaster arterioles exposed to angiotensin II for 30 min, which was not seen with NBT (9 +/- 4%). The vasodilation to tempol was reduced by 68 +/- 6% by catalase. We conclude that the transient relaxation of blood vessels by tempol after prolonged exposure to U-46619 or angiotensin II is mediated in part via production of H(2)O(2) and is largely independent of the endothelium and potassium channels.


Assuntos
Antioxidantes/farmacologia , Óxidos N-Cíclicos/farmacologia , Peróxido de Hidrogênio/metabolismo , Músculo Liso Vascular/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacologia , Angiotensina II/metabolismo , Animais , Catalase/metabolismo , Células Cultivadas , Relação Dose-Resposta a Droga , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Técnicas In Vitro , Masculino , Artérias Mesentéricas/efeitos dos fármacos , Artérias Mesentéricas/metabolismo , Camundongos , Músculo Liso Vascular/enzimologia , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/enzimologia , Miócitos de Músculo Liso/metabolismo , Nitroazul de Tetrazólio/farmacologia , Norepinefrina/farmacologia , Canais de Potássio/efeitos dos fármacos , Canais de Potássio/metabolismo , Ratos , Ratos Endogâmicos SHR , Marcadores de Spin , Superóxido Dismutase/metabolismo , Superóxidos/metabolismo , Vasoconstritores/farmacologia
8.
Biochem J ; 406(1): 105-14, 2007 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-17501721

RESUMO

NOX4 is an enigmatic member of the NOX (NADPH oxidase) family of ROS (reactive oxygen species)-generating NADPH oxidases. NOX4 has a wide tissue distribution, but the physiological function and activation mechanisms are largely unknown, and its pharmacology is poorly understood. We have generated cell lines expressing NOX4 upon tetracycline induction. Tetracycline induced a rapid increase in NOX4 mRNA (1 h) followed closely (2 h) by a release of ROS. Upon tetracycline withdrawal, NOX4 mRNA levels and ROS release decreased rapidly (<24 h). In membrane preparations, NOX4 activity was selective for NADPH over NADH and did not require the addition of cytosol. The pharmacological profile of NOX4 was distinct from other NOX isoforms: DPI (diphenyleneiodonium chloride) and thioridazine inhibited the enzyme efficiently, whereas apocynin and gliotoxin did not (IC(50)>100 muM). The pattern of NOX4-dependent ROS generation was unique: (i) ROS release upon NOX4 induction was spontaneous without need for a stimulus, and (ii) the type of ROS released from NOX4-expressing cells was H(2)O(2), whereas superoxide (O(2)(-)) was almost undetectable. Probes that allow detection of intracellular O(2)(-) generation yielded differential results: DHE (dihydroethidium) fluorescence and ACP (1-acetoxy-3-carboxy-2,2,5,5-tetramethylpyrrolidine) ESR measurements did not detect any NOX4 signal, whereas a robust signal was observed with NBT. Thus NOX4 probably generates O(2)(-) within an intracellular compartment that is accessible to NBT (Nitro Blue Tetrazolium), but not to DHE or ACP. In conclusion, NOX4 has a distinct pharmacology and pattern of ROS generation. The close correlation between NOX4 mRNA and ROS generation might hint towards a function as an inducible NOX isoform.


Assuntos
NADPH Oxidases/genética , Espécies Reativas de Oxigênio/metabolismo , Animais , Linhagem Celular , Membrana Celular/efeitos dos fármacos , Membrana Celular/enzimologia , Citosol/efeitos dos fármacos , Citosol/enzimologia , Espectroscopia de Ressonância de Spin Eletrônica , Indução Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Etídio/análogos & derivados , Etídio/farmacologia , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Humanos , Peróxido de Hidrogênio/farmacologia , Camundongos , Mitocôndrias/efeitos dos fármacos , NAD/metabolismo , NADP/metabolismo , NADPH Oxidase 4 , Nitroazul de Tetrazólio/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Superóxidos/metabolismo , Tetraciclina/farmacologia , Fatores de Tempo
9.
Vascul Pharmacol ; 46(1): 24-34, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16861049

RESUMO

OBJECTIVE: The aim of this study was to provide evidence that peroxynitrite may differentially affect the function of arginine vasopressin (AVP) V(1a) receptors and alpha(1)-adrenoceptors in vascular smooth muscle of the rat METHODS: The vasoconstrictor responses elicited by AVP, or the alpha(1)-adrenoceptor agonist, phenylephrine, were determined in anesthetized rats before and after injections of (i) peroxynitrite, the thiol chelator, para-hydroxymercurobenzoic acid (PHMBA), or the electron acceptor, nitroblue tetrazolium (NBT). The ability of the reducing agent, glutathione, to reverse the loss of response to phenylephrine and AVP in peroxynitrite-treated rats was also examined. RESULTS: The AVP-induced responses were suppressed 10-20 min but not 60-70 min after the administration of peroxynitrite. Glutathione reversed the above loss of response to AVP at 10-20 min. The responses elicited by phenylephrine were suppressed 10-20 min and 60-70 min after administration of peroxynitrite. Glutathione did not reverse the above losses of response to phenylephrine. In addition, the vasoconstrictor actions of AVP and phenylephrine were markedly suppressed after administration of PHMBA or nitroblue tetrazolium. CONCLUSIONS: The above findings provide evidence that exogenously administered peroxynitrite may differentially affect the function of AVP V(1a) receptors and alpha(1)-adrenoceptors in vascular smooth muscle of the rat. The possibility that peroxynitrite impairs AVP V(1a) receptor function by transient oxidation events whereas peroxynitrite impairs alpha(1)-adrenoceptor function by transient oxidation and permanent nitration events will be discussed.


Assuntos
Músculo Liso Vascular/efeitos dos fármacos , Ácido Peroxinitroso/farmacologia , Receptores Adrenérgicos alfa 1/efeitos dos fármacos , Receptores de Vasopressinas/efeitos dos fármacos , Vasoconstrição/efeitos dos fármacos , Animais , Aorta Abdominal/efeitos dos fármacos , Arginina Vasopressina/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Glutationa/farmacologia , Hidroximercuribenzoatos/farmacologia , Masculino , Artéria Mesentérica Superior/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Nitratos/metabolismo , Nitroazul de Tetrazólio/farmacologia , Oxirredução/efeitos dos fármacos , Ácido Peroxinitroso/metabolismo , Fenilefrina/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores Adrenérgicos alfa 1/metabolismo , Receptores de Vasopressinas/metabolismo , Artéria Renal/efeitos dos fármacos , Fatores de Tempo , Resistência Vascular/efeitos dos fármacos , Vasoconstritores/farmacologia
10.
Adv Med Sci ; 52: 143-6, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18217407

RESUMO

PURPOSE: Granulocyte-colony stimulating factor stimulates proliferation and maturation of granulocyte precursor cells. The influence of this hematopoietic factor on phagocytic function of granulocytes was performed in in vitro experiments. The aim was to find, whether G-CSF applicated to children with neutropenia after chemotherapy influences phagocytic functions of neutrophils and whether evaluated parameters depend on a time of G-CSF injection? MATERIAL AND METHODS: The investigation was conducted on a group of 26 children with cancer, treated with granulocyte-colony stimulating factor in the cause of neutropenia after chemotherapy. The control group included 29 healthy children. The blood was taken before the stimulator injection and after 2 and 5 granulocyte-colony stimulating factor injections. The percentage of phagocyting cells and the phagocytic index of granulocytes were determined in heparinized whole blood samples. Oxygen metabolism was evaluated in the absence and presence endotoxin by nitroblue tetrazolium reduction. RESULTS: It was found that granulocyte-colony stimulating factor activates phagocytic functions of neutrophils by normalizing low values of phagocytic index and number of granulocytes, reducing dye nitroblue tetrazolium reduction and increasing the number of phagocytic cells. CONCLUSION: Based on obtained results we can conclude that granulocyte-colony stimulating factor apart from granulopoiesis stimulation can also increase phagocytic and oxidative capacity of granulocytes after chemotherapy.


Assuntos
Fator Estimulador de Colônias de Granulócitos/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neutropenia/patologia , Neutrófilos/metabolismo , Adolescente , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacologia , Criança , Feminino , Granulócitos/efeitos dos fármacos , Granulócitos/metabolismo , Humanos , Masculino , Neutropenia/metabolismo , Neutrófilos/efeitos dos fármacos , Nitroazul de Tetrazólio/farmacologia , Fagocitose/efeitos dos fármacos , Fatores de Tempo
11.
Arch Iran Med ; 9(4): 335-8, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17061605

RESUMO

BACKGROUND: Analysis of the functional activity of neutrophils is of great importance in the differential diagnosis of patients with recurrent bacterial infections. It has long been established that stimulated polymorphonuclear leukocytes reduce nitroblue tetrazolium. Application of a simple and reliable nitroblue tetrazolium method that clearly differentiates the chronic granulomatous disease patients and heterozygote carriers in some groups suspected to have chronic granulomatous disease was investigated. METHODS: This study consisted of 197 samples taken from 100 children (2 - 24-month-old) and 81 neonates (aged < 2 months) referred to our center either due to a suspected bacterial infection or suspected immunodeficiency. The sample also included 16 cord blood samples. Fifty healthy adult individuals were enrolled in this study and were diagnosed as normal control. Neutrophil reduction of nitroblue tetrazolium can be stimulated in vitro by protein kinase agonists such as phorbol myristate acetate, resulting in release of superoxide anion. RESULTS: Phorbol myristate acetate is an exceptionally powerful stimulant and when used in conjunction with glass adherence, caused nearly all normal neutrophils to become transformed and reduced nitroblue tetrazolium to formazan deposits. Of 197 blood samples, 9 were diagnosed as having unrelated chronic granulomatous disease and 7 were carriers of X-linked or autosomal recessive chronic granulomatous disease. The carriers had a range of 15 - 75% stimulated neutrophils. CONCLUSION: We have established a phorbol myristate acetate-stimulated nitroblue tetrazolium test for detection of chronic granulomatous disease patients, which clearly differentiates the chronic granulomatous disease patients from heterozygote carriers. The results in cord fetal blood indicate that this test may be used for antenatal diagnosis of affected boys, carrier females, and autosomal recessive variants of chronic granulomatous disease. The technique is simple, fast, inexpensive, and requires only a few microliters of blood.


Assuntos
Doença Granulomatosa Crônica/diagnóstico , Doença Granulomatosa Crônica/genética , Heterozigoto , Nitroazul de Tetrazólio/farmacologia , Diagnóstico Pré-Natal/métodos , Pré-Escolar , Feminino , Sangue Fetal/metabolismo , Humanos , Indicadores e Reagentes/farmacologia , Lactente , Recém-Nascido , Masculino , Microscopia/instrumentação , Microscopia/métodos , Neutrófilos/metabolismo , Fagocitose , Gravidez , Diagnóstico Pré-Natal/instrumentação , Acetato de Tetradecanoilforbol/farmacologia
12.
Biol Res ; 39(2): 281-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16874403

RESUMO

Free radicals induce numerous diseases by lipid peroxidation, protein peroxidation, and DNA damage. It has been reported that numerous plant extracts have antioxidant activities to scavenge free radicals. Whether Polygonum aviculare L. (Polygonaceae) has antioxidant activity is unknown. In this study, dried Polygonum aviculare L. was extracted by ethanol, and the extract was lyophilized. The antioxidant activities of extract powder were examined by free radical scavenging assays, superoxide radical scavenging assays, lipid peroxidation assays and hydroxyl radical-induced DNA strand scission assays. The results show that the IC50 value of Polygonum aviculare L. extract is 50 microg/ml in free radical scavenging assays, 0.8 microg/ml in superoxide radical scavenging assays, and 15 microg/ml in lipid peroxidation assays, respectively. Furthermore, Polygonum aviculare L. extract has DNA protective effect in hydroxyl radical-induced DNA strand scission assays. The total phenolics and flavonoid content of extract is 677.4 +/- 62.7 microg/g and 112.7 +/- 13 microg/g. The results indicate that Polygonum aviculare L. extract clearly has antioxidant effects.


Assuntos
Antioxidantes/farmacologia , Dano ao DNA/efeitos dos fármacos , Depuradores de Radicais Livres/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Polygonum/química , Animais , Compostos de Bifenilo , Flavonoides/análise , Hidroxibenzoatos/análise , Concentração Inibidora 50 , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Nitroazul de Tetrazólio/farmacologia , Picratos/farmacologia , Extratos Vegetais/farmacologia , Tiobarbitúricos/farmacologia
13.
Respir Res ; 7: 93, 2006 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-16808843

RESUMO

BACKGROUND: Acute alveolar hypoxia causes pulmonary vasoconstriction (HPV) which serves to match lung perfusion to ventilation. The underlying mechanisms are not fully resolved yet. The major vascular segment contributing to HPV, the intra-acinar artery, is mostly located in that part of the lung that cannot be selectively reached by the presently available techniques, e.g. hemodynamic studies of isolated perfused lungs, recordings from dissected proximal arterial segments or analysis of subpleural vessels. The aim of the present study was to establish a model which allows the investigation of HPV and its underlying mechanisms in small intra-acinar arteries. METHODS: Intra-acinar arteries of the mouse lung were studied in 200 mum thick precision-cut lung slices (PCLS). The organisation of the muscle coat of these vessels was characterized by alpha-smooth muscle actin immunohistochemistry. Basic features of intra-acinar HPV were characterized, and then the impact of reactive oxygen species (ROS) scavengers, inhibitors of the respiratory chain and Krebs cycle metabolites was analysed. RESULTS: Intra-acinar arteries are equipped with a discontinuous spiral of alpha-smooth muscle actin-immunoreactive cells. They exhibit a monophasic HPV (medium gassed with 1% O2) that started to fade after 40 min and was lost after 80 min. This HPV, but not vasoconstriction induced by the thromboxane analogue U46619, was effectively blocked by nitro blue tetrazolium and diphenyleniodonium, indicating the involvement of ROS and flavoproteins. Inhibition of mitochondrial complexes II (3-nitropropionic acid, thenoyltrifluoroacetone) and III (antimycin A) specifically interfered with HPV, whereas blockade of complex IV (sodium azide) unspecifically inhibited both HPV and U46619-induced constriction. Succinate blocked HPV whereas fumarate had minor effects on vasoconstriction. CONCLUSION: This study establishes the first model for investigation of basic characteristics of HPV directly in intra-acinar murine pulmonary vessels. The data are consistent with a critical involvement of ROS, flavoproteins, and of mitochondrial complexes II and III in intra-acinar HPV. In view of the lack of specificity of any of the classical inhibitors used in such types of experiments, validation awaits the use of appropriate knockout strains and siRNA interference, for which the present model represents a well-suited approach.


Assuntos
Pulmão/irrigação sanguínea , Músculo Liso Vascular/fisiopatologia , Artéria Pulmonar/fisiopatologia , Vasoconstrição , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico , Animais , Antimicina A/farmacologia , Hipóxia Celular , Complexo II de Transporte de Elétrons/antagonistas & inibidores , Complexo II de Transporte de Elétrons/metabolismo , Complexo III da Cadeia de Transporte de Elétrons/antagonistas & inibidores , Complexo III da Cadeia de Transporte de Elétrons/metabolismo , Inibidores Enzimáticos/farmacologia , Depuradores de Radicais Livres/farmacologia , Técnicas In Vitro , Camundongos , Modelos Animais , Músculo Liso Vascular/metabolismo , Doadores de Óxido Nítrico/farmacologia , Nitrocompostos/farmacologia , Nitroazul de Tetrazólio/farmacologia , Propionatos/farmacologia , Artéria Pulmonar/metabolismo , Vasoconstrição/efeitos dos fármacos , Vasoconstritores , Vasodilatação , Vasodilatadores/farmacologia
14.
J Mater Sci Mater Med ; 17(5): 427-35, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16688583

RESUMO

Superoxide dismutase (SOD) was chemically bound to carboxymethyl-cellulose (CMC) polymer.Furthermore, SOD was also trapped into two hydrogels of CMC with 50% and 90% crosslinking degree. The ability of the two SOD-CMC hydrogels to capture SOD and their release kinetics were investigated. ATR FT-IR spectrometry was used to study the conformation of SOD interacting with both CMC polymer and hydrogels. The effect of SOD-CMC polymer conjugate and SOD-CMC hydrogel systems upon human fibroblasts was studied in vitro measuring the cell proliferation inhibition index and evaluating cell morphology. Using the xanthine oxidase-nitroblue tetrazolium assay, the specific activity of bound SOD to CMC polymer or trapped into hydrogels was evaluated. The specific activity of the enzyme was higher in SOD-CMC hydrogels than in SOD-CMC polymer conjugates.


Assuntos
Anti-Inflamatórios/farmacologia , Carboximetilcelulose Sódica/química , Celulose/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Polímeros/química , Superóxido Dismutase/química , Materiais Biocompatíveis/química , Proliferação de Células , Fibroblastos/metabolismo , Humanos , Hidrogéis/química , Teste de Materiais , Microscopia Eletrônica de Varredura , Nitroazul de Tetrazólio/farmacologia , Espectrofotometria Atômica , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Xantina Oxidase/química
15.
Eur J Pharmacol ; 535(1-3): 248-52, 2006 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-16527267

RESUMO

This study determined the effects of the lipophobic electron acceptor, nitroblue tetrazolium (5 micromol/kg, i.v.) on the vasoconstrictor responses elicited by the 5-hydroxytryptamine2 (5-HT2) receptor agonist, alpha-methyl-5-HT (5-50 microg/kg, i.v.) and the alpha1-adrenoceptor agonist, phenylephrine (2.5-20 microg/kg, i.v.) in conscious Sprague-Dawley rats. The systemic injection of nitroblue tetrazolium elicited pronounced hemodynamic responses that subsided by 10-15 min. Prior to the administration of nitroblue tetrazolium, the injections of alpha-methyl-5-HT and phenylephrine elicited dose-dependent increases in mean arterial blood pressure and mesenteric, renal and hindquarter vascular resistances. After administration of nitroblue tetrazolium, the vasoconstrictor responses elicited by alpha-methyl-5-HT were augmented whereas those elicited by phenylephrine were diminished. These results are consistent with the possibility that nitroblue tetrazolium interacts with the extracellular ligand-binding domains of 5-HT2 receptors and alpha1-adrenoceptor and that this interaction has opposite effects on activities of these G protein coupled receptors.


Assuntos
Agonistas de Receptores Adrenérgicos alfa 1 , Pressão Sanguínea/efeitos dos fármacos , Nitroazul de Tetrazólio/farmacologia , Agonistas do Receptor 5-HT2 de Serotonina , Resistência Vascular/efeitos dos fármacos , Antagonistas de Receptores Adrenérgicos alfa 1 , Antagonistas Adrenérgicos alfa/administração & dosagem , Antagonistas Adrenérgicos alfa/farmacologia , Amidinas/administração & dosagem , Amidinas/farmacologia , Animais , Pressão Sanguínea/fisiologia , Estado de Consciência , Relação Dose-Resposta a Droga , Interações Medicamentosas , Indicadores e Reagentes/farmacologia , Injeções Intravenosas , Masculino , Fenilefrina/administração & dosagem , Fenilefrina/farmacologia , Prazosina/administração & dosagem , Prazosina/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores Adrenérgicos alfa 1/fisiologia , Receptores 5-HT2 de Serotonina/fisiologia , Serotonina/administração & dosagem , Serotonina/análogos & derivados , Serotonina/farmacologia , Antagonistas da Serotonina/administração & dosagem , Antagonistas da Serotonina/farmacologia , Agonistas do Receptor de Serotonina/administração & dosagem , Agonistas do Receptor de Serotonina/farmacologia , Resistência Vascular/fisiologia
16.
Biol. Res ; 39(2): 281-288, 2006. ilus, tab
Artigo em Inglês | LILACS | ID: lil-432430

RESUMO

Free radicals induce numerous diseases by lipid peroxidation, protein peroxidation, and DNA damage. It has been reported that numerous plant extracts have antioxidant activities to scavenge free radicals. Whether Polygonum aviculare L. (Polygonaceae) has antioxidant activity is unknown. In this study, dried Polygonum aviculare L. was extracted by ethanol, and the extract was lyophilized. The antioxidant activities of extract powder were examined by free radical scavenging assays, superoxide radical scavenging assays, lipid peroxidation assays and hydroxyl radical-induced DNA strand scission assays. The results show that the IC50 value of Polygonum aviculare L. extract is 50 µg/ml in free radical scavenging assays, 0.8 µg/ml in superoxide radical scavenging assays, and 15 µg/ml in lipid peroxidation assays, respectively. Furthermore, Polygonum aviculare L. extract has DNA protective effect in hydroxyl radical-induced DNA strand scission assays. The total phenolics and flavonoid content of extract is 677.4 ± 62.7 µg/g and 112.7 ± 13 µg/g. The results indicate that Polygonum aviculare L. extract clearly has antioxidant effects.


Assuntos
Animais , Masculino , Camundongos , Antioxidantes/farmacologia , Dano ao DNA/efeitos dos fármacos , Depuradores de Radicais Livres/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Polygonum/química , Flavonoides/análise , Hidroxibenzoatos , Camundongos Endogâmicos BALB C , Nitroazul de Tetrazólio/farmacologia , Picratos/farmacologia , Extratos Vegetais/farmacologia , Tiobarbitúricos/farmacologia
17.
Mol Cell Biochem ; 275(1-2): 127-33, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16335792

RESUMO

18:1/docosahexaenoic acid (DHA)-containing phosphatidylethanolamine (PE) enhanced cell differentiation and growth inhibition of HL-60 induced by dibutyryl cAMP (dbcAMP) in a dose-dependent manner. The combined treatment of 200 microM dbcAMP and 50 microM 18:1/DHA-PE increased the NBT reducing activity, which is as an indicator of cell differentiation, to more than 75% from 40% of cells treated with 200 microM dbcAMP alone. In HL-60 cells treated with 50 microM 18:1/DHA-PE and 200 microM dbcAMP for 24 h, the expression level of c-jun mRNA and c-Jun protein were remarkably elevated compared to cells treated with dbcAMP alone. In contrast, there was no difference in the expression levels of c-fos mRNA and c-Fos protein between the combination of 18:1/DHA-PE + dbcAMP or dbcAMP alone. On the other hand, the combine treatment of 18:1/DHA-PE and dbcAMP markedly reduced the expression level of c-myc oncogene during 48 h incubation. The decreases of c-myc mRNA by 18:1/DHA-PE and/or dbcAMP was correlated with growth inhibition effect. Thus, 18:1/DHA-PE might enhance dbcAMP-induced HL-60 cell differentiation and growth inhibition by regulation of c-jun and c-myc mRNA and their products.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Ácidos Docosa-Hexaenoicos/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genes jun/fisiologia , Genes myc/fisiologia , Fosfatidiletanolaminas/metabolismo , Bucladesina/metabolismo , Bucladesina/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Ácidos Docosa-Hexaenoicos/metabolismo , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Inibidores Enzimáticos/farmacologia , Genes jun/efeitos dos fármacos , Genes myc/efeitos dos fármacos , Células HL-60 , Humanos , Nitroazul de Tetrazólio/farmacologia , Proteínas Proto-Oncogênicas c-jun/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , RNA Mensageiro/metabolismo , Fatores de Tempo
18.
Indian J Exp Biol ; 43(11): 963-74, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16315393

RESUMO

Numerous factors influence male fertility. Among these factors is oxidative stress (OS), which has elicited an enormous interest in researchers in recent period. Reactive oxygen species (ROS) are continuously produced by various metabolic and physiologic processes. OS occurs when the delicate balance between the production of ROS and the inherent antioxidant capacity of the organism is distorted. Spermatozoa are particularly sensitive to ROS as their plasma membrane contains polyunsaturated fatty acids (PUFA), which oxidizes easily. They also lack cytoplasm to generate a robust preventive and repair mechanism against ROS. The transition metal ions that are found in the body have a catalytic effect in the generation of ROS. Lifestyle behaviours such as smoking and alcohol use and environmental pollution further enhance the generation of ROS and thus, cause destructive effects on various cellular organelles like mitochondria, sperm DNA etc. This article analyzes the detrimental effects of OS on male fertility, measurement of OS and effective ways to decrease or eliminate them completely. We have also provided information on oxidative stress in other systems of the body, which may be applied to future research in the field of reproductive biology.


Assuntos
Fertilidade , Estresse Oxidativo , Animais , Antioxidantes/química , Antioxidantes/metabolismo , Citocromos c/metabolismo , DNA/metabolismo , Ácidos Graxos Insaturados/metabolismo , Humanos , Indicadores e Reagentes/farmacologia , Infertilidade Masculina/patologia , Peroxidação de Lipídeos , Masculino , Modelos Químicos , Nitroazul de Tetrazólio/farmacologia , Espécies Reativas de Oxigênio , Sêmen/metabolismo , Fumar , Espermatozoides/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/química
19.
Chest ; 128(6 Suppl): 556S-558S, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16373824

RESUMO

Hypoxia-induced pulmonary vasoconstriction (HPV) is an important adaptive process that remains incompletely understood. In preconstricted rat pulmonary arteries (inner diameter, 250 to 400 microm), hypoxia (pO2 approximately 10 mm Hg) induces an initial transient phase and a more slowly developing sustained phase of vasoconstriction. Since the release of calcium ions (Ca2+) from intracellular stores by redox-sensitive intracellular Ca2+ release channels known as ryanodine receptors (RyRs) in pulmonary arterial smooth-muscle cells (PASMCs) may play a role in HPV, and considerable evidence now supports that levels of reactive oxygen species (ROS) are paradoxically increased in PASMC under hypoxia, we investigated whether redox activation of RyRs by ROS may transduce HPV. By reverse transcriptase-polymerase chain reaction, we found that all three RyR isoforms are expressed in rat pulmonary arteries and in PASMCs. The sustained phase, but not the transient phase, of HPV can be prevented by pretreating pulmonary arteries with RyR inhibitors ryanodine (200 micromol/L) or dantrolene (50 micromol/L). The addition of dantrolene, ryanodine or the thiol-reducing agent dithiothreitol (1 mmol/L) during the sustained phase of HPV reversed the hypoxic vasoconstriction. In contrast, the superoxide scavenger nitroblue tetrazolium (500 nmol/L) prevented further hypoxic pulmonary vasoconstriction during the sustained phase of HPV but did not reverse it. Taken together, our data suggest that redox activation of RyRs by ROS has an important role in transducing the sustained contraction of pulmonary arteries under hypoxia.


Assuntos
Hipóxia/fisiopatologia , Pulmão/irrigação sanguínea , Artéria Pulmonar/fisiopatologia , Canal de Liberação de Cálcio do Receptor de Rianodina/fisiologia , Vasoconstrição/fisiologia , Animais , Cálcio/metabolismo , Dantroleno/farmacologia , Técnicas In Vitro , Masculino , Nitroazul de Tetrazólio/farmacologia , Oxirredução , Ratos , Ratos Wistar , Rianodina/farmacologia
20.
J Cardiovasc Pharmacol ; 46(5): 660-71, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16220074

RESUMO

The main aim of this study was to determine the effects of the lipophobic electron acceptor, nitroblue tetrazolium (NBT), on the vasodilator responses elicited by femoral vein injections of L- and D-S-nitrosocysteine (L- and D-SNC), L- and D-S-nitroso-beta,beta-dimethylcysteine (L- and D-SNPEN) and the nitric oxide (NO) donor, MAHMA NONOate, in pentobarbital-anesthetized rats. L- and D-SNC, L- and D-SNPEN, and MAHMA NONOate elicited dose-dependent falls in mean arterial blood pressure (MAP), and hindquarter (HQR), renal (RR), and mesenteric (MR) vascular resistances. The L-SNC- and L-SNPEN-induced depressor and vasodilator responses were markedly attenuated after injection of NBT. The D-SNC- and D-SNPEN-induced falls in mean arterial pressure, hindquarter, and mesenteric vascular resistances were also reduced after injection of nitroblue tetrazolium whereas the falls in renal resistances were not affected. However, nitroblue tetrazolium inhibited the L-SNC and L-SNPEN responses much more profoundly than the D-SNC and D-SNPEN responses in each vascular bed. In contrast, the MAHMA NONOate-induced responses were not attenuated by nitroblue tetrazolium. This study demonstrates that nitroblue tetrazolium attenuates L- and D-SNC-and L- and D-SNPEN- mediated but not NO-mediated vasodilation. The lack of effects of NBT on the NO responses suggests that NBT does not interfere with the intracellular mechanisms by which NO relaxes vascular smooth muscle. The more pronounced effects of NBT on the vasodilator effects of L-SNC and L-SNPEN than D-SNC and D-SNPEN suggests that these stereoisomers differentially interact with stereoselective S-nitrosothiol recognition sites in the vasculature and that these sites (or their signaling elements) contain thiol residues that may be susceptible to occupation and/or oxidation (ie, disulfide-bond formation) by nitroblue tetrazolium.


Assuntos
Hemodinâmica/efeitos dos fármacos , S-Nitrosotióis/farmacologia , Animais , Sítios de Ligação , Pressão Sanguínea/efeitos dos fármacos , Relação Dose-Resposta a Droga , Masculino , Doadores de Óxido Nítrico/farmacologia , Nitroazul de Tetrazólio/farmacologia , Ratos , Ratos Sprague-Dawley , S-Nitrosotióis/química , Estereoisomerismo , Resistência Vascular/efeitos dos fármacos
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