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1.
Plant Sci ; 287: 110198, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31481193

RESUMO

Aiming to counteract B deficiency impacts, plants have developed different strategies in order to reach an optimal growth in soils with limited B availability. These include B transport mechanisms that involves a facilitated transport, via channel proteins, and a high-affinity active transport driven by borate transporters. The AtNIP5;1 channel protein is a member of Major Intrinsic Protein family which facilitates B influx into the roots under low B supply. In order to explore the phytohormone-dependent regulation of AtNIP5;1, the effects of abscisic acid (ABA), ethylene, auxins and cytokinins on the activity of AtNIP5;1 promoter were evaluated using the reporter line pNIP5;1-GUS. The results show that ABA treatment increased pAtNIP5;1 activity. Besides, a larger B uptake was found following ABA treatment under B deficiency suggesting a role of ABA inducing B uptake. The ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC) caused an induction of AtNIP5;1 expression although did not correlate with higher B concentrations nor with an improvement in root growth. On the contrary, auxins and cytokinins caused slight changes in pAtNIP5;1 induction. Altogether, these results show a regulatory role of phytohormones in AtNIP5;1 promoter what may affect B transport. The herein provided information may contribute to better understand the regulation of B transport in plants towards minimizing B deficiency impacts on agriculture.


Assuntos
Aquaporinas/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Boro/metabolismo , Regulação da Expressão Gênica de Plantas , Reguladores de Crescimento de Plantas/metabolismo , Ácido Abscísico/metabolismo , Aquaporinas/genética , Arabidopsis/citologia , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Transporte Biológico , Citocininas/metabolismo , Etilenos/metabolismo , Genes Reporter , Ácidos Indolacéticos/metabolismo , Raízes de Plantas/citologia , Raízes de Plantas/genética , Raízes de Plantas/metabolismo
2.
Rev. colomb. enferm ; 17(1): 56-64, Octubre de 2018.
Artigo em Espanhol | LILACS, BDENF - Enfermagem, COLNAL | ID: biblio-987445

RESUMO

Objetivo: validar en el contexto colombiano los instrumentos de percepción de barreras y de beneficios asociados a la realización\r\nde ejercicio en adolescentes basados en el modelo de promoción de la salud de Nola J. Pender. Metodología: los instrumentos\r\nseleccionados fueron sometidos a estos procedimientos: permisos, traducción y pruebas de validez facial, de contenido, de constructo\r\ny de confiabilidad. Resultados: el instrumento de percepción de barreras para el ejercicio tiene un índice de Lawshe\r\nmodificado de 0,83 y un kappa de Fleiss de 0,59 para relevancia y de 0,53 para pertinencia. El instrumento de percepción de\r\nbeneficios por el ejercicio presenta un índice de Lawshe modificado de 0,93 y un kappa de Fleiss para relevancia 0,70 y de 0,91\r\npara pertinencia. El análisis factorial identificó en cada uno de los instrumentos dos factores: barreras para la salud física y afectivas o emocionales; en cuanto a los beneficios se relacionaron con las condiciones ambientales y el tiempo disponible para\r\nrealizar el ejercicio, y la confiabilidad se encontró en 0,82 y 0,83 para la percepción de barreras y de beneficios, respectivamente.\r\nConclusiones: los instrumentos de percepción de barreras y de beneficios para la realización de ejercicio adaptados al contexto\r\ncolombiano son válidos y confiables. Por lo anterior, se consideran apropiados para evaluar y diseñar estrategias que contribuyan\r\na mejorar la realización de actividad física en los adolescentes.


Objective: To validate the instruments for perceiving barriers\r\nand benefits of exercising for Colombian adolescents based on\r\nthe health promotion model of Nola Pender. Methodology:\r\nThe instruments for perceiving barriers and benefits of exercising\r\nwere subject to the following procedures: permits, translation,\r\nback translation, and validity tests: facial, content, and construction.\r\nResults: The instruments for perceiving barriers and\r\nbenefits of exercising have a modified Lawshe index of 0.83 and\r\nFleiss Kappa of 0.59 for relevance and pertinence of 0.53. The\r\ninstruments for perceiving barriers and benefits of exercising\r\nalso present a modified Lawshe index of 0.93 and Fleiss Kappa\r\nfor relevance 0.70 and for pertinence 0.91. The factor analysis\r\nidentified in each of the instruments 2 factors: barriers to physical\r\nand affective or emotional health; in terms of benefits, they\r\nwere related to environmental conditions and the time available\r\nto perform the exercise, and reliability was found in 0.82 and 0.83\r\nfor the barrier and benefits perceptions, respectively. Conclusions:\r\nThe instruments for perceiving barriers and benefits of\r\nexercising adapted to the Colombian context are valid and reliable.\r\nTherefore, they are considered appropriate for evaluating\r\nand designing strategies that contribute to improving the\r\nperformance of physical activity in adolescents.


Objetivo: validar no contexto colombiano os instrumentos de\r\npercepção de barreiras e benefícios para a realização de exercício\r\nem adolescentes com base no modelo de promoção da saúde\r\nde Nola Pender. Metodologia: os instrumentos de percepção\r\nde barreiras e benefícios para o exercício foram submetidos aos\r\nprocedimentos: autorizações, tradução, e testes de validade\r\nfacial, conteúdo e construto e confiabilidade. Resultados: o\r\ninstrumento de Percepção de Barreiras para o exercício possui\r\num índice de Lawshe modificado de 0,83 e Kappa de Fleiss de\r\n0,59 para relevância e pertinência de 0,53. O instrumento de\r\npercepção de benefícios para o exercício também apresenta\r\num índice de Lawshe modificado de 0,93 e Kappa de Fleiss para\r\nrelevância de 0,70 e para pertinência de 0,91. A análise fatorial\r\nidentificou em cada um dos instrumentos 2 fatores: barreiras à\r\nsaúde física e afetiva ou emocional; em termos de benefícios,\r\neles foram relacionados às condições ambientais e ao tempo\r\ndisponível para a realização do exercício, e a confiabilidade\r\nse encontrou em 0,83 e 0,83 para a percepção de barreiras e\r\nbenefícios respectivamente. Conclusões: os instrumentos\r\nde percepção de barreiras e benefícios para a realização de\r\nexercícios adaptados ao contexto colombiano são válidos e\r\nconfiáveis. Por isso, são considerados adequados para avaliar e\r\ndesenhar estratégias que contribuam para melhorar o desempenho\r\nda atividade física em adolescentes.


Assuntos
Exercício Físico , Reprodutibilidade dos Testes
3.
IEEE Trans Biomed Eng ; 60(7): 1776-84, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23358945

RESUMO

This paper presents the design, experimental modeling, and control of a pump-driven renal perfusion pressure (RPP)-regulatory system to implement precise and relatively fast RPP regulation in rats. The mechatronic system is a simple, low-cost, and reliable device to automate the RPP regulation process based on flow-mediated occlusion. Hence, the regulated signal is the RPP measured in the left femoral artery of the rat, and the manipulated variable is the voltage applied to a dc motor that controls the occlusion of the aorta. The control system is implemented in a PC through the LabView software, and a data acquisition board NI USB-6210. A simple first-order linear system is proposed to approximate the dynamics in the experiment. The parameters of the model are chosen to minimize the error between the predicted and experimental output averaged from eight input/output datasets at different RPP operating conditions. A closed-loop servocontrol system based on a pole-placement PD controller plus dead-zone compensation was proposed for this purpose. First, the feedback structure was validated in simulation by considering parameter uncertainty, and constant and time-varying references. Several experimental tests were also conducted to validate in real time the closed-loop performance for stepwise and fast switching references, and the results show the effectiveness of the proposed automatic system to regulate the RPP in the rat, in a precise, accurate (mean error less than 2 mmHg) and relatively fast mode (10-15 s of response time).


Assuntos
Algoritmos , Biorretroalimentação Psicológica/instrumentação , Determinação da Pressão Arterial/instrumentação , Bombas de Infusão , Perfusão/instrumentação , Circulação Renal/fisiologia , Terapia Assistida por Computador/instrumentação , Animais , Pressão Sanguínea/fisiologia , Eletrônica Médica/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Ratos
4.
Rev Esp Quimioter ; 21(3): 189-93, 2008 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-18792821

RESUMO

Introduction. As the number of multidrug-resistant strains of Pseudomonas aeruginosa has risen in the intensive care unit (ICU) of the San Carlos Clinic Hospital, 12 consecutive isolates from different patients were collected to determine the possibility of an epidemic outbreak caused by the spread of a single strain. We determined the antimicrobial susceptibility to the most common agents used in the treatment of infections caused by this bacteria. The results of susceptibility studies suggest that different strains of P. aeruginosa are responsible for the respiratory tract infections in ICU. Methods. The clonal relationship between the isolates using was determined using BOX and ERIC primers by means of repetitive sequence-based polymerase chain reaction (rep-PCR). The in vitro activity of these strains against colistin, rifampicin, doxicycline and azythromycin was studied to determine in which cases the combination of colistin with any of the other three antibiotics was synergistic. Results. Sensitivity studies point out the presence of several strains of P. aeruginosa as the causal agents of respiratory infections produced by this microorganism in the ICU. Combinations of colistin with doxycicline and colistin with azithromycin were synergistic for some isolates in the synergy studies. Discussion. Clonal studies reveal the presence of five different clones among our isolates. Therefore we can conclude that there was no outbreak of P. aeruginosa in the ICU. Synergistic activity of combinations of colistin plus azithromycin, colistin plus doxicycline and colistin plus rifampicin was less than expected and a high percentage of indifferent results was observed.


Assuntos
Antibacterianos/administração & dosagem , Azitromicina/administração & dosagem , Colistina/administração & dosagem , Doxiciclina/administração & dosagem , Farmacorresistência Bacteriana Múltipla , Pseudomonas aeruginosa/efeitos dos fármacos , Rifampina/administração & dosagem , Humanos , Unidades de Terapia Intensiva , Testes de Sensibilidade Microbiana
5.
Rev. esp. quimioter ; 21(3): 189-193, sept. 2008. tab
Artigo em Espanhol | IBECS | ID: ibc-77591

RESUMO

Introducción. Ante el incremento de aislados de Pseudomonasaeruginosa multirresistentes en la Unidad de CuidadosIntensivos (UCI) del Hospital Clínico San Carlos deMadrid y para determinar la posibilidad de que se tratase deun brote epidémico causado por la diseminación de unaúnica cepa, se recogieron 12 muestras consecutivas de distintospacientes que fueron identificadas y a las que posteriormentese determinó su sensibilidad a los antibióticosutilizados habitualmente para el tratamiento de las infeccionesproducidas por este microorganismo.Métodos. Mediante la amplificación de secuencia basadaen la reacción en cadena de la polimerasa (repetitive sequence-based polymerase chain reaction, rep-PCR) se determinó larelación clonal entre los aislados utilizando los primers BOX yERIC y se estudió la actividad in vitro frente a estas cepas decolistina, rifampicina, doxiciclina y azitromicina para determinaren qué casos la combinación de colistina con alguno de losotros tres antibióticos presentaba actividad sinérgica.Resultados. Los estudios de sensibilidad apuntan a la presenciade varias cepas de P. aeruginosa como responsables delas infecciones respiratorias producidas por este microorganismoen la UCI, hecho que fue corroborado mediante los estudiosclonales realizados. En los estudios de sinergia las asociacionesde colistina con doxiciclina y con azitromicina presentaron actividadsinérgica para alguno de los aislados.Discusión. Los resultados de los estudios clonales revelanla presencia de cinco clones diferentes entre los aisladosseleccionados, por lo que podemos concluir que no se tratade un brote de P. aeruginosa en la UCI. La actividad sinérgicade la asociación de colistina con azitromicina, doxiciclinay rifampicina ha sido menor de la esperada y se observa unelevado porcentaje de resultados indiferentes (AU)


Introduction. As the number of multidrug-resistantstrains of Pseudomonas aeruginosa has risen in the intensivecare unit (ICU) of the San Carlos Clinic Hospital,12 consecutive isolates from different patients were collectedto determine the possibility of an epidemic outbreakcaused by the spread of a single strain. We determinedthe antimicrobial susceptibility to the most commonagents used in the treatment of infections caused by thisbacteria. The results of susceptibility studies suggest thatdifferent strains of P. aeruginosa are responsible for therespiratory tract infections in ICU.Methods. The clonal relationship between the isolatesusing was determined using BOX and ERIC primersby means of repetitive sequence-based polymerase chainreaction (rep-PCR). The in vitro activity of these strainsagainst colistin, rifampicin, doxicycline and azythromycinwas studied to determine in which cases the combinationof colistin with any of the other three antibioticswas synergistic.Results. Sensitivity studies point out the presence ofseveral strains of P. aeruginosa as the causal agents ofrespiratory infections produced by this microorganism inthe ICU. Combinations of colistin with doxycicline andcolistin with azithromycin were synergistic for some isolatesin the synergy studies.Discussion. Clonal studies reveal the presence of fivedifferent clones among our isolates. Therefore we canconclude that there was no outbreak of P. aeruginosa inthe ICU. Synergistic activity of combinations of colistinplus azithromycin, colistin plus doxicycline and colistinplus rifampicin was less than expected and a high percentageof indifferent results was observed (AU)


Assuntos
Humanos , Masculino , Feminino , Pseudomonas aeruginosa , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Pseudomonas aeruginosa/fisiologia , Pseudomonas aeruginosa/patogenicidade , Infecção Hospitalar/complicações , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/etiologia , Infecção Hospitalar/prevenção & controle , Infecção Hospitalar/terapia , Colistina/análogos & derivados , Colistina/administração & dosagem , Colistina/biossíntese , Colistina/farmacocinética , Colistina/uso terapêutico , Testes de Sensibilidade Microbiana/métodos , Testes de Sensibilidade Microbiana/tendências , Testes de Sensibilidade Microbiana
6.
J Asthma ; 41(6): 639-43, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15584313

RESUMO

BACKGROUND: Allergen-specific conjunctival challenge is a fruitful and complete tool in evaluating pathophysiological phenomena of allergic inflammation. After challenge, a significant neutrophil infiltrate occurred in allergic subjects. The primary (azurophilic) granules of neutrophils contain a variety of enzymes that might potentiate inflammation, such as myeloperoxidase (MPO). It is not known whether allergen-specific conjunctival challenge (ASCC) is able to elicit MPO release. We also investigated the possible role of immunotherapy (IT) in the release of MPO. METHOD: The groups studied included Dactylis glomerata-sensitive adult atopic patients suffering from seasonal allergic rhinoconjunctivitis, and healthy adult nonatopic volunteer controls. One group of allergic patients received no specific hyposensitization (not-IT allergic group). A second group of allergic patients had been immunotherapy-treated with Dactylis glomerata extract for the preceding three years and continued to receive a maintenance dose within the highest potency of the extract (IT-allergic group). ASCC with Dactylis glomerata was performed outside the pollen season in all subjects. Myeloperoxidase was assayed by MPO-enzyme immunoassay method. RESULTS: Thirty minutes after challenge, myeloperoxidase levels in the non-immunotherapy allergic patients were significantly higher compared than in the healthy group (p<0.001). The levels of myeloperoxidase released in the immunotherapy allergic group were significantly lower than those in the nonimmunotherapy allergic group (p<0.001) and higher than those in nonallergic subjects (p<0.001). CONCLUSION: These results indicate that after ASCC there is a release of MPO. Our study suggests that immunotherapy actively modifies the release of MPO after ASCC.


Assuntos
Alérgenos/farmacologia , Túnica Conjuntiva/efeitos dos fármacos , Conjuntivite Alérgica/imunologia , Peroxidase/metabolismo , Rinite Alérgica Perene/enzimologia , Alérgenos/efeitos adversos , Estudos de Casos e Controles , Conjuntivite Alérgica/diagnóstico , Técnicas de Diagnóstico do Sistema Respiratório , Feminino , Humanos , Imunoterapia/métodos , Masculino , Testes do Emplastro , Peroxidase/análise , Probabilidade , Valores de Referência , Rinite Alérgica Perene/imunologia , Rinite Alérgica Perene/terapia , Sensibilidade e Especificidade
7.
Microbiology (Reading) ; 150(Pt 11): 3731-3739, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15528659

RESUMO

The impact of calcium signals in virtually all cells has led to the study of their role in prokaryotic organisms as stress response modulators. Cell differentiation in adverse conditions is a common Ca(2+)-requiring response. Nitrogen starvation induces the differentiation of N(2)-fixing heterocysts in the filamentous cyanobacterium Anabaena sp. PCC7120. This paper reports the use of a recombinant strain of this organism expressing the photoprotein aequorin to monitor the intracellular free-calcium concentration during the course of heterocyst differentiation. A specific calcium signature that is triggered exclusively when cells are deprived of combined nitrogen and generated by intracellular calcium stores was identified. The intracellular calcium signal was manipulated by treatment with specific calcium drugs, and the effect of such manipulation on the process of heterocyst differentiation was subsequently assessed. Suppression, magnification or poor regulation of this signal prevented the process of heterocyst differentiation, thereby suggesting that a calcium signal with a defined set of kinetic parameters may be required for differentiation. A hetR mutant of Anabaena sp. PCC7120 that cannot differentiate into heterocysts retains, however, the capacity to generate the calcium transient in response to nitrogen deprivation, strongly suggesting that Ca(2+) may be involved in a very early step of the differentiation process.


Assuntos
Anabaena/crescimento & desenvolvimento , Anabaena/metabolismo , Sinalização do Cálcio , Cálcio/metabolismo , Regulação Bacteriana da Expressão Gênica , Adaptação Fisiológica , Equorina/genética , Equorina/metabolismo , Anabaena/citologia , Anabaena/genética , Proteínas de Bactérias/genética , Citoplasma/química , Deleção de Genes , Genes Reporter , Nitrogênio/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
9.
Alergol. inmunol. clín. (Ed. impr.) ; 19(1): 7-12, feb. 2004. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-135166

RESUMO

Aunque desde hace años se ha implicado al eosinófilo en la fisiopatología de los procesos alérgicos mediados por la lgE todavía no se conocen lo mecanismo exactos que atraen a esta células al órgano de choque del proceso atópico. Por una parte se habla de la propia presencia de lo tres receptores de la lgE (Fcel R, FccRII y galectina 3) en los eosinófilos de los pacientes alérgicos. pero si exite es mínima. Y por la otra no e ha podido activar a esos eosinófilo mediante un mecanismo mediado por la IgE. Pero el neutrófilo. que es una célula cuya participación en la respuesta alérgica es cada día más evidente, posee también los tres receptores de la IgE y. al contrario de lo que sucede en los eosinófilo . puede activarse a través de un mecanismo dependiente de la lgE como nuestro grupo ha demostrado en reiterada ocasiones. En este artículo comentamos como la activación mediada por la lgE de los neutrófilos puede modular la respuesta de los eosinófilos en los procesos atópicos (AU)


Even though the eosinophil has been implicated in the pathophysiology of IgE­mediated allergic processes for many a year. the precise mechanism that attract the e cells to the target organ of the aiopic proces are a yet unknown. Sorne author invoke the presence of the three lgE receptor (Fcalk. FccRII and gallectin 3) on the eosinophils of allergic patient ; yet, if so. such a presence is minimal. Furthermore. it ha not been posible to activate those eosinophil through an IgE­mediated mechanim. However, the neutrophil, a cell who e participation in the allergic repone i increasingly evident, al o possese the three IgE receptor and, to the contrary of what happen with the eosinophil. it can be activated through an IgE­mediated rnechanism, a our group has repeatedly hown. We here di cus how IgE­mediated neutrophil activation may modulate the repone of eosinophil in atopic procese (AU)


Assuntos
Humanos , Hipersensibilidade Imediata/imunologia , Neutrófilos/imunologia , Eosinófilos/imunologia , Síndrome de Job/imunologia , Ativação de Neutrófilo/imunologia
11.
Acta Radiol ; 45(8): 810-4, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15690609

RESUMO

Gallbladder duplication is a rare event, with an incidence at autopsy of about 1/4000, with very few documented symptomatic cases reported. Preoperative diagnosis and differentiation of this malformation are important to prevent inadvertent damage to the biliary system, a complicated postoperative course, and repeat surgery. We present a case of true gallbladder duplication found incidentally during abdominal ultrasonography (US). The diagnosis was made with US and the Y-type duplication was demonstrated with magnetic resonance cholangiopancreatography (MRCP).


Assuntos
Vesícula Biliar/anormalidades , Adulto , Vesícula Biliar/diagnóstico por imagem , Humanos , Masculino , Ultrassonografia
12.
Allergy ; 58(10): 1027-32, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14510721

RESUMO

BACKGROUND: CD14 is a most important monocyte surface molecule. Recently, it has been reported that there is an important relationship between CD14 and immunoglobulin E, and that regulation of CD14 expression is an effector mechanism mediating apoptosis of monocytes. OBJECTIVE: The present study was designed to determine whether specific allergens were able to modulate CD14 expression and apoptosis by monocytes from allergic patients or whether specific immunotherapy (IT) might affect these processes. METHODS: One group of adult allergic asthmatic patients had received IT for the previous 3 years. Another similar group was not treated with IT. We challenged peripheral blood monocytes from both groups of asthmatic patients in vitro with the specific allergen that produced clinical symptoms in asthmatic patients. The cells were also challenged with allergen to which the patients were not sensitive. Monocytes from normal subjects were also challenged with allergens. Expression of CD14 on the monocyte surface was analyzed by flow cytometry, and soluble CD14 (sCD14) in culture supernatant by enzyme-linked immunosorbent assay. The three groups of subjects were challenged with allergens, and apoptosis was analyzed by flow cytometry. RESULTS: When monocytes from non-IT-treated asthmatic patients were cultivated with the allergens to which the patients were sensitive, a significant up-regulation on the monocyte surface was observed compared with results from the healthy group (P < 0.003) and from the IT asthmatic group (P < 0.003). A significantly higher sCD14 level was observed in the culture supernatant of the monocytes from the IT asthmatic group were observed compared with those from the healthy group (P < 0.001) and those from the non-IT asthmatic group (P < 0.001). A significantly higher apoptosis level was observed in monocytes from the IT asthmatic group compared with those from the healthy group (P < 0.001) and those from the non-IT asthmatic group (<0.001). CONCLUSIONS: We present evidence that the expression of CD14 on the surface of monocytes and the apoptosis of the same cells can be modulated by an allergen-dependent mechanism. These processes can be affected by IT.


Assuntos
Alérgenos/imunologia , Apoptose , Asma/imunologia , Hipersensibilidade Imediata/imunologia , Receptores de Lipopolissacarídeos/metabolismo , Monócitos/imunologia , Adulto , Asma/terapia , Humanos , Hipersensibilidade Imediata/patologia , Hipersensibilidade Imediata/terapia
15.
J Asthma ; 39(7): 619-24, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12442951

RESUMO

BACKGROUND: The role of oxygen radicals has been implicated in disease processes of asthma. We have previously shown that specific allergens were able to activate respiratory burst by neutrophils from allergic patients sensitized to allergens of the same type as those which produce clinical allergy. OBJECTIVES: In this study, we attempted to evaluate the production of respiratory burst by an anti-IgE Ab in neutrophils from asthmatic allergic patients (with and without immunotherapy treatment) and in neutrophils from healthy subjects. METHOD: Neutrophils were stimulated by 10 microg/mL of anti-IgE Ab for 15 min at 37 degrees C. The production of respiratory burst from neutrophils was assayed by luminol-amplified chemiluminescence method. RESULTS: The respiratory burst was significantly higher in neutrophils from non-IT-asthmatic patients than in neutrophils from both healthy (p < 0.001) and IT-asthmatic (p < 0.001) groups. The IT-asthmatic group presented levels of respiratory burst approximately equal to those from non-allergic subjects (p=0.426). CONCLUSIONS: We conclude that neutrophils obtained from allergic asthmatic patients have an increased propensity to generate respiratory bursts, in comparison with neutrophils from healthy subjects. Immunotherapy actively modifies the respiratory burst by neutrophils from allergic asthmatic patients.


Assuntos
Asma/imunologia , Neutrófilos/imunologia , Anticorpos/imunologia , Humanos , Imunoglobulina E/imunologia , Imunoterapia , Medições Luminescentes , Explosão Respiratória
17.
Clin Exp Allergy ; 31(6): 889-92, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11422153

RESUMO

BACKGROUND: The three forms of IgE receptor: the heterotrimeric high-affinity receptor for IgE (FcepsilonRI), the low-affinity receptor for IgE (FcepsilonRII/CD23) and the Mac-2/IgE-binding protein (epsilonBP), have previously been found on human neutrophils. We have previously shown that specific allergens are able to activate functional responses by neutrophils from allergic patients sensitized to those allergens. Neutrophils are present in the sites of allergic inflammation. The primary (azurophilic) granules of neutrophils contain a variety of enzymes that might potentiate inflammation, such as myeloperoxidase (MPO). It is not known whether specific allergens are able to elicit MPO release by neutrophils from allergic patients. METHODS: Neutrophils were challenged in vitro with the specific allergen that produced clinical symptoms in asthmatic patients. Also, the cells were challenged with allergens that the patients were not sensitive to. Neutrophils from normal subjects were also challenged with allergens. RESULTS: The in vitro challenge of neutrophils with allergens that the patients were sensitive to elicited a release of MPO by these cells. The in vitro activation of neutrophils was highly allergen-specific, in such a way that allergens other than those accounting for clinical symptoms did not evoke MPO release, and allergens were ineffective on neutrophils from healthy donors. CONCLUSION: An IgE-dependent mechanism might promote MPO release by neutrophils at allergic sites.


Assuntos
Asma/sangue , Hipersensibilidade Imediata/sangue , Neutrófilos/enzimologia , Peroxidase/metabolismo , Receptores de IgE/fisiologia , Adulto , Relação Dose-Resposta Imunológica , Humanos
18.
Mol Plant Microbe Interact ; 14(5): 663-70, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11332730

RESUMO

Symbiosome development was studied in pea root nodules from plants growing in the absence of boron (B). Rhizobia released into the host cells of nodules from B-deficient plants developed to abnormal endophytic forms with an altered electrophoretic lipopolysaccharide pattern. Immunostaining after sodium dodecyl sulfate-polyacrylamide gel electrophoresis and electroblotting of nodule homogenates with antibodies that recognize glycoprotein components showed that two previously described lectin-like glycoproteins (PsNLEC-1A and PsNLEC-1B) did not harbor the carbohydrate epitope normally recognized by specific monoclonal antibodies. Material derived from B-deficient nodules, however, still contained three antigenic isoforms with similar electrophoretic mobilities to PsNLEC-1 isoforms A, B, and C. These could be detected following immunoblotting and immunostaining with a specific antiserum originating from the purified PsNLEC protein that had been heterologously expressed in Escherichia coli. Immunogold localization of PsNLEC-1 sugar epitopes in B-deficient nodules showed that they were associated mostly with cytoplasmic vesicles rather than normal localization in the symbiosome compartment of mature infected cells. These results suggest that a modification of the glycosyl-moieties of PsNLEC-1 and an alteration of vesicle targeting occur during the development of pea nodules in the absence of B, and that these changes are associated with the development of aberrant nonfunctional symbiosomes.


Assuntos
Boro/deficiência , Glicoproteínas/metabolismo , Pisum sativum/fisiologia , Proteínas de Plantas/metabolismo , Rhizobium leguminosarum/fisiologia , Animais , Anticorpos Monoclonais , Glicoproteínas/análise , Glicoproteínas/química , Glicosilação , Immunoblotting , Microscopia Eletrônica , Pisum sativum/microbiologia , Proteínas de Plantas/análise , Proteínas de Plantas/química , Raízes de Plantas/microbiologia , Raízes de Plantas/fisiologia , Raízes de Plantas/ultraestrutura , Ratos , Rhizobium leguminosarum/isolamento & purificação , Rhizobium leguminosarum/patogenicidade
20.
J Allergy Clin Immunol ; 107(4): 623-6, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11295649

RESUMO

BACKGROUND: There is increasing evidence of neutrophil participation in asthma and the allergic process. After activation, neutrophils release myeloperoxidase (MPO) together with other granule enzymes. OBJECTIVES: In this study we attempted to evaluate the release of MPO in vitro by neutrophils from asthmatic patients and the relationship between neutrophil degranulation and lung function, measured as FEV(1), of the patients. We also investigated the possible role of immunotherapy in the release of MPO by neutrophils. METHODS: Neutrophils were stimulated with formyl-methionyl-leucyl-phenylalanine for 45 minutes at 37 degrees C. MPO released from neutrophils was assayed by using an MPO enzyme immunoassay. RESULTS: Neutrophils released statistically significantly higher MPO levels in the asthmatic patients not receiving immunotherapy than in the healthy group. A significant inverse correlation was observed in the asthmatic group not receiving immunotherapy between MPO secretion and lung function, measured as FEV(1), of the patients. Neutrophils of the asthmatic group receiving immunotherapy released significantly less MPO than did those of the asthmatic group not receiving immunotherapy, with MPO levels equal to those from nonallergic subjects. CONCLUSIONS: We conclude that neutrophils obtained from allergic asthmatic patients have an increased propensity to release MPO. The experiments described here provide evidence that there is a significant inverse relationship between levels of MPO released by neutrophils from allergic patients and lung function, as assessed by FEV(1). Our study suggests that immunotherapy actively modifies the release of MPO in vitro by neutrophils from allergic asthmatic patients.


Assuntos
Asma/imunologia , Neutrófilos/enzimologia , Peroxidase/metabolismo , Adulto , Asma/terapia , Degranulação Celular , Relação Dose-Resposta a Droga , Volume Expiratório Forçado , Humanos , Imunoterapia , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Neutrófilos/efeitos dos fármacos
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