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1.
Artículo en Inglés | MEDLINE | ID: mdl-21370724

RESUMEN

BACKGROUND: Leukotrienes, especially LTC4, are important inflammatory mediators in allergic and nonallergic inflammation of the entire airways. Of particular interest are numerous theories regarding the pathogenesis of aspirin intolerance with subsequent hyperproduction of leukotrienes and inhibition of cyclooxygenase. OBJECTIVE: To examine the influence of the cysteinyl-leukotriene receptor antagonist montelukast on clinical symptoms and inflammatory markers in nasal lavage fluid in patients with bronchial asthma and nasal polyps, and determine its dependency on aspirin sensitization. METHODS: Twenty-four patients (7 women, 17 men; median age, 55.5 years) with nasal polyps and controlled asthma (n=12 with aspirin intolerance) were treated with 10 mg montelukast once daily for 6 weeks in a blinded, placebo-controlled fashion. The placebo phase was randomly assigned 4 weeks before (n=12) or after treatment (n=12). Symptom score, rhinoendoscopy, rhinomanometry, smears for eosinophils, and nasal lavages for the determination of different mediators were performed. RESULTS: Compared to placebo, there were significant improvements in the nasal symptom score and airflow limitation as well as a reduction in the inflammatory mediators in nasal lavage fluid after treatment. Furthermore, reduced eosinophils in nasal smears and peripheral blood were observed 2 and 6 weeks after treatment. CONCLUSION: Leukotriene 1 receptor blockade led to a significant decrease in eosinophil inflammation accompanied by a reduction in other mediators such as neurokinin A and substance P in the nasal lavage fluid of patients with nasal polyps and asthma, with or without aspirin intolerance.


Asunto(s)
Acetatos/uso terapéutico , Antiinflamatorios no Esteroideos/uso terapéutico , Asma/tratamiento farmacológico , Antagonistas de Leucotrieno/uso terapéutico , Pólipos Nasales/tratamiento farmacológico , Quinolinas/uso terapéutico , Acetatos/administración & dosificación , Adulto , Anciano , Antiinflamatorios no Esteroideos/administración & dosificación , Asma/complicaciones , Asma Inducida por Aspirina/complicaciones , Asma Inducida por Aspirina/tratamiento farmacológico , Recuento de Células , Ciclopropanos , Cisteína/administración & dosificación , Cisteína/antagonistas & inhibidores , Cisteína/uso terapéutico , Eosinófilos/citología , Femenino , Humanos , Antagonistas de Leucotrieno/administración & dosificación , Leucotrienos/administración & dosificación , Leucotrienos/uso terapéutico , Masculino , Persona de Mediana Edad , Líquido del Lavado Nasal/química , Líquido del Lavado Nasal/inmunología , Pólipos Nasales/complicaciones , Neuroquinina A/análisis , Quinolinas/administración & dosificación , Sustancia P/análisis , Sulfuros , Resultado del Tratamiento
2.
J Investig Allergol Clin Immunol ; 20(3): 214-21, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20635787

RESUMEN

OBJECTIVE: Recent guidelines reveal that allergic rhinitis impairs quality of life. Neuropeptides play a central role in allergy-related nasal inflammation. The objective of this study was to analyze the release of neuropeptides (substance P, neurokinin A, and vasoactive intestinal peptide) in nasal lavage and their modification by intranasal fluticasone propionate as an established therapy in patients with allergic rhinitis. METHODS: Eleven patients with proven allergic rhinitis induced by house dust mite were challenged before and after administration of fluticasone propionate nasal spray. Nasal lavage samples were collected after allergen challenge, and neuropeptides were measured using enzyme-linked immunosorbent assay. Values for histamine, protein, and human serum albumin were also recorded. Eight healthy individuals were included as nonatopic controls. RESULTS: The neuropeptides investigated were detectable in nasal lavage fluid in both patients and controls. Treatment with fluticasone propionate significantly decreased clinical response to allergen challenge (P < .01) compared with the controls and led to a decrease in values for substance P, neurokinin A, vasoactive intestinal peptide, histamine release, human serum albumin, and total protein after allergen challenge (P < .01). CONCLUSIONS: The demonstration of proinflammatory neuropeptides in NAL and suppression of their release after allergen challenge caused by a topical corticosteroid suggest a role for neuropeptides in allergic inflammation. Diminished release of neuropeptides induced b fluticasone propionate was accompanied by an improvement in the clinical symptoms of patients with persistent allergic rhinitis.


Asunto(s)
Androstadienos/administración & dosificación , Antialérgicos/administración & dosificación , Antígenos Dermatofagoides/inmunología , Líquido del Lavado Nasal/química , Rinitis Alérgica Perenne/tratamiento farmacológico , Adulto , Anciano , Femenino , Fluticasona , Histamina/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Neuroquinina A/metabolismo , Rinitis Alérgica Perenne/inmunología , Rinitis Alérgica Perenne/metabolismo , Albúmina Sérica/metabolismo , Estadísticas no Paramétricas , Sustancia P/metabolismo , Péptido Intestinal Vasoactivo/metabolismo , Adulto Joven
3.
J Cell Biol ; 99(3): 1140-4, 1984 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-6206077

RESUMEN

The processing and ribonucleoprotein assembly of U4 small nuclear RNA has been investigated in HeLa cells. After a 45-min pulse label with [3H]uridine, a set of apparently cytoplasmic RNAs was observed migrating just behind the gel electrophoretic position of mature U4 RNA. These molecules were estimated to be one to at least seven nucleotides longer than mature U4 RNA. They reacted with Sm autoimmune patient sera and a monoclonal Sm antibody, indicating their association with proteins characteristic of small nuclear ribonucleoprotein complexes. The same set of RNAs was identified by hybrid selection of pulse-labeled RNA with cloned U4 DNA, confirming that these are U4 RNA sequences. No larger nuclear precursors of these RNAs were detected. Pulse-chase experiments revealed a progressive decrease in the radioactivity of the U4 precursor RNAs coincident with an accumulation of labeled mature U4 RNA, confirming a precursor-product relationship.


Asunto(s)
Precursores de Ácido Nucleico/biosíntesis , ARN/biosíntesis , Anticuerpos Monoclonales , Complejo Antígeno-Anticuerpo , Autoanticuerpos , Células HeLa/metabolismo , Humanos , Cinética , Precursores del ARN , ARN Nuclear Pequeño , Ribonucleoproteínas/biosíntesis , Ribonucleoproteínas Nucleares Pequeñas , Tritio , Uridina/metabolismo
4.
J Investig Allergol Clin Immunol ; 19(6): 459-64, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-20128420

RESUMEN

OBJECTIVE: Allergic rhinitis, a disease that impairs quality of life, is characterized by inflammation due to an allergic reaction. Fexofenadine is a second-generation histamine receptor blocker well known for its potent interaction with this inflammatory process. The main aim of this study was to further clarify the anti-inflammatory effects exerted by fexofenadine in patients with intermittent allergic rhinitis. METHODS: Twenty patients with intermittent allergic rhinitis due to birch and mugwort pollen were enrolled. Fexofenadine was administered once a day at a dose of 120 mg. Clinical improvement was assessed by a symptom score, and nasal airway flows were measured by anterior rhinomanometry at baseline and after 2 weeks of treatment with fexofenadine. Nasal smears were tested for eosinophils and nasal lavage fluid were examined for histamine, cysteinyl leukotrienes, soluble intercellular adhesion molecule-1, eosinophil cationic protein, and albumin by enzyme-linked immunosorbent assay. All the tests were performed during the pollen season. RESULTS: Fexofenadine induced a significant improvement in nasal and ocular symptoms (P < .001), nasal edema and secretion (P < .001), and nasal airway flow (P < .001). The clinical improvement was related to a significant reduction in all inflammatory mediators (P < .01 in all cases). CONCLUSION: This study demonstrates that fexofenadine is able to mediate significant changes in different nasal lavage markers from patients with intermittent allergic rhinitis. The changes observed in the markers analyzed in both nasal secretions and serum are attributable to the anti-inflammatory effects of fexofenadine in vivo.


Asunto(s)
Antiinflamatorios/administración & dosificación , Mediadores de Inflamación/inmunología , Líquido del Lavado Nasal/inmunología , Rinitis Alérgica Estacional/tratamiento farmacológico , Terfenadina/análogos & derivados , Adulto , Anciano , Antiinflamatorios/efectos adversos , Antígenos de Plantas/efectos adversos , Antígenos de Plantas/inmunología , Artemisia/inmunología , Betula/inmunología , Progresión de la Enfermedad , Proteína Catiónica del Eosinófilo/análisis , Femenino , Histamina/análisis , Humanos , Mediadores de Inflamación/análisis , Molécula 1 de Adhesión Intercelular/análisis , Leucotrieno D4/análisis , Masculino , Persona de Mediana Edad , Líquido del Lavado Nasal/química , Polen/efectos adversos , Polen/inmunología , Rinitis Alérgica Estacional/inmunología , Terfenadina/administración & dosificación , Terfenadina/efectos adversos , Resultado del Tratamiento
5.
Mol Cell Biol ; 5(9): 2332-40, 1985 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2942763

RESUMEN

Transcription-proximal stages of U1 small nuclear RNA biosynthesis were studied by 32P labeling of nascent chains in isolated HeLa cell nuclei. Labeled RNA was hybridized to nitrocellulose-immobilized, single-stranded M13 DNA clones corresponding to regions within or flanking a human U1 RNA gene. Transcription of U1 RNA was inhibited by greater than 95% by alpha-amanitin at 1 microgram/ml, consistent with previous evidence that it is synthesized by RNA polymerase II. No hybridization to DNA immediately adjacent to the 5' end of mature U1 RNA (-6 to -105 nucleotides) was detected, indicating that, like all studied polymerase II initiation, transcription of U1 RNA starts at or very near the cap site. However, in contrast to previously described transcription units for mRNA, in which equimolar transcription occurs for hundreds or thousands of nucleotides beyond the mature 3' end of the mRNA, labeled U1 RNA hybridization dropped off sharply within a very short region (approximately 60 nucleotides) immediately downstream from the 3' end of mature U1 RNA. Also in contrast to pre-mRNA, which is assembled into ribonucleoprotein (RNP) particles while still nascent RNA chains, the U1 RNA transcribed in isolated nuclei did not form RNP complexes by the criterion of reaction with a monoclonal antibody for the small nuclear RNP Sm proteins. This suggests that, unlike pre-mRNA-RNP particle formation, U1 small nuclear RNP assembly does not occur until after the completion of transcription. These results show that, despite their common synthesis by RNA polymerase II, mRNA and U1 small nuclear RNA differ markedly both in their extents of 3' processing and their temporal patterns of RNP assembly.


Asunto(s)
ARN Nuclear Pequeño/genética , Secuencia de Bases , Núcleo Celular , Células HeLa , Humanos , Hibridación de Ácido Nucleico , Procesamiento Postranscripcional del ARN , ARN Nuclear Pequeño/biosíntesis , Ribonucleoproteínas/análisis , Ribonucleoproteínas Nucleares Pequeñas , Transcripción Genética
6.
Mol Cell Biol ; 13(8): 4670-8, 1993 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8336708

RESUMEN

The promoters of vertebrate U6 small nuclear RNA genes contain a distal control region whose presence results in at least an eightfold level of transcriptional activation in vivo. Previous transfection experiments have demonstrated that most of the distal control region of a human U6 gene resides in a restriction fragment located from -244 to -149 relative to the transcriptional start site. Three octamer-related motifs that bind recombinant Oct-1 transcription factor in vitro exist in this segment of DNA. However, transfection of human 293 cells with various plasmid templates in which these Oct-1 binding sites had been disrupted individually or in combination showed that only the consensus octamer motif located between positions -221 to -214 was functional. Even so, the consensus octamer motif mutant template was expressed at only a moderately reduced level relative to the wild-type promoter. When another octamer-related sequence located nearby, one that did not bind Oct-1 in vitro, was disrupted along with the perfect octamer site, expression was reduced fivefold in transfected cells. A factor that binds this functional, nonconsensus octamer site (NONOCT) was detected in crude cellular extracts. However, the NONOCT sequence was not essential for activation, since its disruption caused only a 40% reduction in U6 gene expression, and mutagenesis to convert the NONOCT sequence to a consensus octamer motif restored wild-type expression. Furthermore, in vitro transcription of a human U6 proximal promoter joined to a single copy of the octamer motif was stimulated by the addition of recombinant Oct-1 protein.


Asunto(s)
Regiones Promotoras Genéticas , ARN Nuclear Pequeño/genética , Secuencia de Bases , Línea Celular , Análisis Mutacional de ADN , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Regulación de la Expresión Génica , Genes , Factor C1 de la Célula Huésped , Humanos , Técnicas In Vitro , Datos de Secuencia Molecular , Factor 1 de Transcripción de Unión a Octámeros , Oligodesoxirribonucleótidos/química , Mutación Puntual , Proteínas Recombinantes/metabolismo , Secuencias Reguladoras de Ácidos Nucleicos , Factores de Transcripción/genética , Transcripción Genética
7.
Nucleic Acids Res ; 27(21): 4269-75, 1999 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-10518620

RESUMEN

Telomerase is a ribonucleoprotein reverse transcriptase that synthesizes and maintains telomeric DNA. Studies of telomeres and telomerase are facilitated by the large number of linear DNA molecules found in ciliated protozoa, such as Tetrahymena thermophila. To examine the expression of telomerase, we investigated the transcription of the RNA polymerase III-directed gene encoding the RNA subunit (TER1) of this enzyme. A chimeric gene containing the Glaucoma chattoni TER1 transcribed region flanked by 5' and 3' Tetrahymena regions was used to identify promoter elements following transformation of Tetrahymena cells. Disruption of a conserved proximal sequence element (PSE) located at -55 in the Tetrahymena TER1 5' flanking region eliminated expression of the chimeric gene. In addition, mutation of an A/T-rich element at -25 decreased expression markedly. A gel mobility shift assay and protein-DNA cross-linking identified a PSE-binding polypeptide of 50-60 kDa in Tetrahymena extracts. Gel filtration analysis revealed a native molecular mass of approximately 160 kDa for this binding activity. Our results point to a similar architecture between ciliate telomerase RNA and metazoan U6 small nuclear RNA promoters.


Asunto(s)
Regulación de la Expresión Génica , Regiones Promotoras Genéticas/genética , ARN Protozoario/genética , Telomerasa/genética , Tetrahymena thermophila/enzimología , Tetrahymena thermophila/genética , Animales , Secuencia de Bases , Línea Celular , Secuencia Conservada/genética , ADN Protozoario/química , ADN Protozoario/genética , ADN Protozoario/metabolismo , ADN Recombinante/genética , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/metabolismo , Dosificación de Gen , Genes Protozoarios/genética , Peso Molecular , Mutación/genética , ARN Polimerasa III/metabolismo , ARN Protozoario/análisis , ARN Nuclear Pequeño/genética , Elementos de Respuesta/genética , Telomerasa/metabolismo , Moldes Genéticos , Tetrahymena thermophila/citología , Tetrahymenina/enzimología , Tetrahymenina/genética , Factores de Transcripción/química , Factores de Transcripción/metabolismo , Transcripción Genética/genética
8.
Clin Rheumatol ; 24(5): 464-8, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15662487

RESUMEN

We report on the unique effects and benefits of autologous stem cell transplantation in childhood systemic lupus erythematosus (SLE) and describe this procedure in two young girls with severe and refractory disease. The patients' stem cells were mobilized with granulocyte colony-stimulating factor (G-CSF) and collected by CS-3000 Blood Cell Separator (Baxter Healthcare, Round Lake, Ill., USA), and the CliniMACS CD34+ cell selection device (Miltenyi Biotech, Bergisch Gladbach, Germany) was used to obtain CD34+ cells. A total of 1.7x10(6) and 1.0x10(6)/kg CD34+ cells were obtained, with 2.0x10(5) and 1.0x10(4)/kg of CD3+ cells remaining, respectively. The conditioning regimen consisted of cyclophosphamide (50 mg/kg per day for 4 days) plus antithymocyte globulin (ATG-Fresenius, 5 mg/kg per day for 3 days). Neutrophil counts recovered within 9 days in both cases. Within 15 days, the platelet counts recovered and were sustained over 100x10(9)/l. Cushingoid features disappeared completely 3 months after transplantation because of the removal of corticosteroid medication. One 13-year-old child increased her height by 5 cm in 6 months after stopping steroids. She had not increased her height in her previous 7 years of disease. As of the time of this report, the first patient remains in clinical and laboratory remission for nearly 4 years, while the second suffered a relapse of thrombocytopenia 9 months post-transplantation. One residual effect of their treatment is that their CD4+ cell counts remained in the lower range after one year of transplant. The effect of this conditioning regimen plus CD34+ autologous stem cell transplantation on these two children with refractory SLE was beneficial, but long-term follow-up data and additional experience with this procedure are required. Autologous stem cell transplantation may limit the long-term toxicity of therapy in childhood SLE.


Asunto(s)
Antígenos CD34/inmunología , Lupus Eritematoso Sistémico/terapia , Trasplante de Células Madre , Trasplante Autólogo , Adolescente , Niño , Ciclofosfamida/uso terapéutico , Femenino , Humanos , Inmunosupresores/uso terapéutico , Resultado del Tratamiento
9.
Gene ; 148(2): 269-75, 1994 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-7958954

RESUMEN

The proximal promoter of a human U6 small nuclear RNA (snRNA)-encoding gene contains two separate elements, the proximal sequence element (PSE) and the TATA box. We investigated the interaction of the PSE- and TATA-binding proteins (PBP and TBP) with normal and mutant U6 proximal promoters using an electrophoretic mobility shift assay. We detected a complex containing both PBP and TBP bound to the wild-type U6 promoter. Efficient formation of the triple complex was dependent on the presence of the PSE and the TATA box on the template DNA. Mutant U6 promoters containing an increased spacing between the PSE and TATA box of 5 or 10 bp were impaired in the ability to form a complex that includes TBP. We infer from these results that PBP and TBP interact when their binding sites are properly positioned in a U6 gene promoter.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Regiones Promotoras Genéticas , ARN Nuclear Pequeño/genética , TATA Box , Factores de Transcripción/metabolismo , Secuencia de Bases , Cartilla de ADN , Humanos , Datos de Secuencia Molecular , Mutación , Proteína de Unión a TATA-Box , Transcripción Genética
10.
J Immunol Methods ; 166(2): 215-21, 1993 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-8288875

RESUMEN

An assay system for the determination of the membrane bound IgD (mIgD) and IgM (mIgM) on B lymphocytes was developed by the combination of two new ELISA methods with the results of flow cytometry after labeling with specific antibodies. The mIgD and mIgM of B lymphocytes were prepared by incubating mononuclear cells (MNCs) in Tween 20 containing buffer and repeated freeze/thaw cycles. Optimal results were achieved with 0.2-0.4% Tween 20 and two freezing cycles. With biotin-streptavidin amplification the sensitivity of the ELISA was 30 microU/ml for IgD and 0.5 ng/ml for IgM. In healthy persons 3.5 +/- 0.5 mU mIgD were detected on 10(6) IgD+ cells and 57.1 +/- 5.9 ng mIgM on 10(6) IgM+ cells. The mIgD/mIgM ratio was 0.065 +/- 0.005 mU/ng. The developed ELISA systems utilize only commercially available reagents and therefore provide a convenient reproducible tool for determining membrane bound IgD and IgM on B lymphocytes.


Asunto(s)
Linfocitos B/metabolismo , Inmunoglobulina D/sangre , Inmunoglobulina M/sangre , Receptores de Antígenos de Linfocitos B/sangre , Adulto , Separación Celular , Ensayo de Inmunoadsorción Enzimática , Femenino , Citometría de Flujo , Humanos , Leucocitos Mononucleares/metabolismo , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad
11.
Br J Pharmacol ; 108(2): 293-5, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8448580

RESUMEN

To establish that bradykinin is formed in the heart we measured bradykinin in the venous effluent from rat isolated hearts perfused with Krebs-Henseleit buffer. In addition, we examined the effect on bradykinin outflow of the angiotensin converting enzyme (ACE) inhibitor, ramiprilat. From rat isolated normoxic hearts a bradykinin outflow of 0.85 +/- 0.1 ng ml-1 perfusate g-1 wet weight was measured. Perfusion with ramiprilat increased the bradykinin concentration to 2.8 +/- 0.3 ng ml-1 perfusate g-1 wet weight. During ischaemia bradykinin outflow maximally increased 8.2 fold to 7.0 +/- 0.5 ng ml-1 perfusate g-1, and in ramiprilat-perfused hearts 5.8 fold to 16.0 +/- 1.8 ng ml-1 perfusate g-1. In the reperfusion period bradykinin outflow normalized to values measured in the respective pre-ischaemic period. The presents data show that bradykinin is continuously formed in the rat isolated heart. Ischaemia increases bradykinin outflow from the heart. Presumably by inhibiting degradation of kinins, ACE inhibition significantly increased the bradykinin concentration during normoxia, ischaemia and reperfusion.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Bradiquinina/metabolismo , Isquemia Miocárdica/metabolismo , Ramipril/análogos & derivados , Animales , Soluciones Cardiopléjicas , Glucosa , Técnicas In Vitro , Masculino , Preservación de Órganos , Ramipril/farmacología , Ratas , Ratas Wistar , Trometamina
12.
Chest ; 103(5): 1477-81, 1993 May.
Artículo en Inglés | MEDLINE | ID: mdl-8486030

RESUMEN

The clinical course of congestive heart failure (CHF) and mitral valve stenosis (MVS) is accompanied by episodes of dyspnea, wheezing, and cough, symptoms also observed in patients with bronchial hyperreactivity. However, it is still controversial whether bronchial hyperreactivity is demonstrable in patients with chronic overload of the pulmonary circulation. In order to examine the effects of CHF on the respiratory function, we performed pulmonary function tests, titrated bronchial acetylcholine provocations, and left and right heart catheterization in 21 patients with impaired left ventricular function (mean ejection fraction, 37 percent, NYHA class 3), 5 patients with MVS, and 17 control patients with coronary artery disease (mean ejection fraction, 63 percent). Bronchial hyperresponsiveness was defined as an obstructive response to increased doses of inhaled acetylcholine. A 20 percent fall in forced expiratory volume in the first second (FEV1), a 100 percent increase in total airway resistance (Rtot), and a 60 percent reduction of pulmonary conductance (SGtot) were considered positive. Patients with impaired left ventricular function showed significantly higher airway resistance, and lower airway conductance at the maximal tolerated acetylcholine dose compared with control patients. Patients with MVS had a significant lower airway conductance. The induced bronchial obstruction was completely reversible upon inhalation of a beta 2-mimetic. We conclude that chronic overload of the pulmonary circulation is accompanied by bronchial hyperreactivity that may augment the symptoms of dyspnea in patients with CHF and MVS.


Asunto(s)
Hiperreactividad Bronquial/fisiopatología , Insuficiencia Cardíaca/fisiopatología , Estenosis de la Válvula Mitral/fisiopatología , Circulación Pulmonar , Acetilcolina , Adulto , Anciano , Resistencia de las Vías Respiratorias , Hiperreactividad Bronquial/etiología , Pruebas de Provocación Bronquial , Cateterismo Cardíaco , Enfermedad Coronaria/complicaciones , Enfermedad Coronaria/fisiopatología , Femenino , Volumen Espiratorio Forzado , Insuficiencia Cardíaca/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Estenosis de la Válvula Mitral/complicaciones
13.
Peptides ; 17(1): 25-30, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8822506

RESUMEN

Exogenous substance P (10-80 nmol/ml) induced a dose-dependent increase in nasal symptoms in asymptomatic allergics with rhinitis (n = 15) and controls (n = 8), but did not release any mediators. However, comparing the antigen-evoked release of mediators into nasal secretions with that of a substance P-pretreated antigen challenge, we found a significant enhancement of kinins, TAME esterase activity (p < 0.05-0.01), and histamine (p < 0.001, NS) 10-20 min after antigen challenge. These results suggest 1) that substance P-induced increase in nasal congestion is mediated through direct neurokinin receptor activation independently of mast cell activation, and 2) that during the allergic reaction there is a substance P-mast cell interaction that enhances the mediator response to nasal allergen challenge.


Asunto(s)
Alérgenos/administración & dosificación , Mucosa Nasal/efectos de los fármacos , Mucosa Nasal/inmunología , Sustancia P/farmacología , Adulto , Bradiquinina/metabolismo , Relación Dosis-Respuesta a Droga , Femenino , Liberación de Histamina/efectos de los fármacos , Humanos , Inmunoglobulina E/metabolismo , Masculino , Mastocitos/efectos de los fármacos , Mastocitos/fisiología , Péptido Hidrolasas/metabolismo , Rinitis Alérgica Estacional/etiología , Rinitis Alérgica Estacional/inmunología , Sustancia P/administración & dosificación , Sustancia P/fisiología
14.
Peptides ; 21(3): 359-64, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10793217

RESUMEN

There is accumulating evidence that tachykinins are implicated in inflammation, including asthma. Therefore, we hypothesized that the neutral endopeptidase (NEP), under challenge conditions, could be affected. Serum from 21 asthmatics and six healthy volunteers was sampled before, 30, and 120 min after allergen challenge. NEP-IR was determined using an ELISA and was found in all subjects. Compared to prechallenge, no difference was seen between asthmatics and controls; however, under challenge conditions, NEP-IR in asthmatics was significantly lower (30 min, P = 0.058; 120 min, P = 0.0017, respectively). This finding supports indirectly the hypothesis that tachykinins are released during allergen exposure, and suggests a regulatory role of NEP.


Asunto(s)
Alérgenos/farmacología , Asma/sangre , Neprilisina/sangre , Administración por Inhalación , Adulto , Alérgenos/administración & dosificación , Asma/enzimología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valores de Referencia , Factores de Tiempo
15.
Peptides ; 16(7): 1273-8, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8545250

RESUMEN

Endothelial neutral endopeptidase (EC 3.4.24.11, NEP) contributes to the inactivation of vasoactive and inflammatory peptides such as f-Met-Leu-Phe, substance P, atrial natriuretic peptide, and bradykinin. The aim of the present study was to investigate the cellular regulation of NEP expression in human endothelial cells, focusing on the role of cyclic nucleotides and cellular phosphodiesterases (PDE). Activation of adenylate cyclase by forskolin or prostaglandin E1 (PGE1) induced an increase of NEP activity and NEP protein after 24 h of incubation. This effect was mimicked by two activators of protein kinase A, dibutyryl-cAMP and 8-bromo-cAMP. The nonspecific PDE inhibitor, 3-isobutyl-1-methylxanthine (200 microM), increased NEP activity up to 192%. The activator of guanylate cyclase, sodium nitroprusside (SNP), did not affect NEP activity but completely inhibited the 3-isobutyl-1-methylxanthine-mediated increase of NEP activity. The PDE-III inhibitors motapizone (100 microM) and enoximone (100 microM) enhanced NEP activity up to 188% and 213%, the PDE-IV inhibitor rolipram (3 microM) up to 162%, and the combined PDE-III/IV inhibitor zardaverine (1 microM) up to 176% of control values. The present data provide evidence for a cAMP-mediated increase of NEP activity in human endothelial cells.


Asunto(s)
Adenilil Ciclasas/metabolismo , Endotelio Vascular/metabolismo , Regulación Enzimológica de la Expresión Génica , Neprilisina/biosíntesis , Inhibidores de Fosfodiesterasa/farmacología , Piridazinas/farmacología , Secuencia de Aminoácidos , Células Cultivadas , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/enzimología , Activación Enzimática , Ensayo de Inmunoadsorción Enzimática , Guanilato Ciclasa/metabolismo , Humanos , Datos de Secuencia Molecular , Transducción de Señal , Venas Umbilicales
16.
Peptides ; 15(5): 843-8, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7527144

RESUMEN

We describe the development of a new ELISA for the detection of neural endopeptidase 3.4.24.11 (NEP). Neutral endopeptidase 3.4.24.11 was determined in preparations of human granulocytes, mononuclear cells (MNC), and in serum. Human recombinant NEP was used as reference. Specificity of the mAbs was tested using APAAP, FACS analysis, and Western blot analysis. Lysis of the blood cells was performed by incubating the cells with 0.4% Tween-20 and repeated freezing cycles. The minimal detectable dose for recombinant NEP was 15 pg/ml. The recovery was 94 +/- 9%. The NEP was detectable in 15 out of 20 serum samples of 20 volunteers (mean +/- SEM, 245 +/- 88 pg/ml, n = 20)) and in all granulocyte preparations (1176 +/- 138 pg/10(7) cells, n = 20)). The results were reproducible among replicates (CV = 3 +/- 1%, n = 40), dilutions (CV = 8 +/- 2%, n = 5), and assays (CV = 12 +/- 4%, n = 5). With this new ELISA, a simple and reproducible method for the measurement of NEP 3.4.24.11 is described.


Asunto(s)
Leucocitos/enzimología , Neprilisina/sangre , Western Blotting , Separación Celular , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Humanos , Coloración y Etiquetado
17.
Regul Pept ; 97(2-3): 181-6, 2001 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-11164954

RESUMEN

Neutral endopeptidase (NEP) is described in airways as the major degrading enzyme of tachykinins such as neurokinin A (NKA) and substance P (SP). Due to its localization and mode of action NEP may play a role in the pathophysiology of bronchial reactivity (BR) especially under the aspect of neurogenic inflammation. Serum NEP concentrations were measured by ELISA to investigate if there is a correlation between serum NEP and the degree of bronchial reactivity expressed by PC20-FEV1 histamine(.). PC20-FEV1 histamine was determined in 31 asthmatic patients [age 31.9+/-1.3 years (mean+/-SEM) FEV1=92.1+/-2.4% (mean+/-SEM) 16 females/15 males]. Prior to the histamine challenge blood samples were obtained and stored at -70 degrees C until determination using ELISA. A significant correlation between serum NEP and the PC20-FEV1 (n=31, r=0.49, P<0.01) was found. The results suggest that serum NEP is modulating neuropeptide-induced effects in the pathophysiology of airway responsiveness.


Asunto(s)
Hiperreactividad Bronquial/enzimología , Neprilisina/sangre , Adulto , Ensayo de Inmunoadsorción Enzimática , Femenino , Volumen Espiratorio Forzado , Histamina/sangre , Humanos , Masculino , Sensibilidad y Especificidad
18.
Neuropeptides ; 30(2): 117-24, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8771553

RESUMEN

The determination of substance P (SP) concentrations in human nasal lavages can be used to monitor physiological and certain pathophysiological processes in human airway mucosa. But, because of the low concentrations, immunoassays of high sensitivity are needed. Two approaches to improve the sensitivity of the radioimmunological determinations of SP are compared: increasing the sample volume and miniaturizing the assay design. The characterization of SP-like immunoreactivity (SP-LIR) in human nasal lavage was performed by investigating the immunological specificity of the antibody used in the radioimmunoassays and by reversed-phase high-performance liquid chromatography separation of the SP-LIR. SP concentrations in nasal lavages can be reliably measured by each of the two introduced RIA methods. Despite the lower detection limit of the miniaturized immunoassay (0.2 in comparison to 1.3 fmol/incubate) it is advisable to increase the sample volume in order to improve the sensitivity because of the higher precision of the determinations. SP-LIR was found in nasal lavage specimens in concentrations between 2 and 10 fmol/ml and consisted of authentic SP and, to a less extent, SP-sulfoxide.


Asunto(s)
Líquido del Lavado Nasal/química , Sustancia P/análisis , Cromatografía Líquida de Alta Presión , Humanos , Fragmentos de Péptidos/análisis , Radioinmunoensayo/métodos , Radioinmunoensayo/estadística & datos numéricos , Sensibilidad y Especificidad , Estereoisomerismo
19.
Gene Expr ; 6(2): 59-72, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8979085

RESUMEN

Vertebrate small nuclear RNA (snRNA) gene promoters contain a distal, enhancer-like region that is composed of an octamer motif adjacent to at least one other element. Here we show that a human U6 snRNA distal region contains a SPH motif previously found in several chicken snRNA gene enhancers and the 5'-flanking region of vertebrate selenocysteine tRNA genes. SPH binding factor (SBF) was detected in either chicken or HeLa cell extracts that could bind SPH elements in a species-independent manner. Both human and chicken SBF required divalent cation to bind effectively to DNA. DNase I footprinting experiments indicated that human SBF specifically protected the human U6 SPH element. Furthermore, a SBF polypeptide of approximately 85 kDa was detected in both HeLa and chicken extracts following ultraviolet light-mediated cross-linking to human U6 or chicken U4 SPH elements. A part of the human U6 SPH element was quite sensitive to mutation, as demonstrated by both specific protein binding and transcription assays. From these data it is apparent that the distal regions of some RNA polymerase III- and RNA polymerase II-transcribed small RNA promoters are virtually identical in composition, and their mechanisms of transcriptional activation are possibly quite similar.


Asunto(s)
Regiones Promotoras Genéticas , ARN Nuclear/genética , Proteínas de Unión al ARN/genética , Animales , Pollos , Células HeLa , Humanos , Unión Proteica , ARN Nuclear/metabolismo , Proteínas de Unión al ARN/metabolismo , Homología de Secuencia de Ácido Nucleico , Transcripción Genética
20.
Respir Med ; 92 Suppl A: 17-22, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9850359

RESUMEN

Beclomethasone dipropionate (BDP) has been reformulated in a chlorofluorocarbon-free propellant, hydrofluoroalkane-134a (HFA), resulting in an extrafine aerosol which gives improved drug delivery to the airways. The objective of this 6 week, placebo-controlled study was to evaluate the clinical efficacy of HFA-BDP 400 micrograms day-1 in 256 adult patients with moderate asthma. This is a lower daily dose than that recommended for existing BDP inhalers in current treatment guidelines for moderate asthma (NIH publication 95-3659). Another objective was to evaluate whether delivering the 400 micrograms dose as four actuations of 50 micrograms twice daily (HFA-BDP 50 micrograms) provided equivalent asthma control to delivering the dose as two actuations of 100 micrograms twice daily (HFA-BDP 100 micrograms) without the use of a spacer or holding chamber. Both active treatments produced a significant change from baseline in morning peak expiratory flow (PEF), which was significantly larger than that in the placebo group (P < or = 0.017) throughout the study. The mean changes from baseline in morning PEF at weeks 5-6 were 47.0 l min-1 in the combined HFA-BDP group and 16.5 l min-1 in the HFA-placebo group. The two dose strengths were statistically equivalent (P = 0.017 for equivalence testing). The active treatments also produced significant improvements compared with placebo in evening PEF, forced expiratory volume in the first second, forced expiratory flow over 25-75% of vital capacity, sleep disturbance scores and daily beta-agonist use. The study medication was well tolerated, with a low incidence of adverse events. The results from this study demonstrate that a daily dose of 400 micrograms HFA-BDP (given in 50 micrograms and 100 micrograms strengths) provides dose proportionality and effective control in patients with moderate asthma.


Asunto(s)
Propelentes de Aerosoles , Antiinflamatorios/administración & dosificación , Beclometasona/administración & dosificación , Hidrocarburos Fluorados , Administración por Inhalación , Adulto , Aerosoles , Antiinflamatorios/uso terapéutico , Beclometasona/uso terapéutico , Método Doble Ciego , Esquema de Medicación , Femenino , Humanos , Masculino , Tamaño de la Partícula
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