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2.
J Allergy Clin Immunol ; 132(5): 1068-1074.e1, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24084072

RESUMEN

BACKGROUND: Tiotropium has activity as an asthma controller. However, predictors of a positive response to tiotropium have not been described. OBJECTIVE: We sought to describe individual and differential responses of asthmatic patients to salmeterol and tiotropium when added to an inhaled corticosteroid, as well as predictors of a positive clinical response. METHODS: Data from the double-blind, 3-way, crossover National Heart, Lung, and Blood Institute's Asthma Clinical Research Network's Tiotropium Bromide as an Alternative to Increased Inhaled Glucocorticoid in Patients Inadequately Controlled on a Lower Dose of Inhaled Corticosteroid (ClinicalTrials.gov number, NCT00565266) trial were analyzed for individual and differential treatment responses to salmeterol and tiotropium and predictors of a positive response to the end points FEV1, morning peak expiratory flow (PEF), and asthma control days (ACDs). RESULTS: Although approximately equal numbers of patients showed a differential response to salmeterol and tiotropium in terms of morning PEF (n = 90 and 78, respectively) and ACDs (n = 49 and 53, respectively), more showed a differential response to tiotropium for FEV1 (n = 104) than salmeterol (n = 62). An acute response to a short-acting bronchodilator, especially albuterol, predicted a positive clinical response to tiotropium for FEV1 (odds ratio, 4.08; 95% CI, 2.00-8.31; P < .001) and morning PEF (odds ratio, 2.12; 95% CI, 1.12-4.01; P = 0.021), as did a decreased FEV1/forced vital capacity ratio (FEV1 response increased 0.39% of baseline for every 1% decrease in FEV1/forced vital capacity ratio). Higher cholinergic tone was also a predictor, whereas ethnicity, sex, atopy, IgE level, sputum eosinophil count, fraction of exhaled nitric oxide, asthma duration, and body mass index were not. CONCLUSION: Although these results require confirmation, predictors of a positive clinical response to tiotropium include a positive response to albuterol and airway obstruction, factors that could help identify appropriate patients for this therapy.


Asunto(s)
Agonistas de Receptores Adrenérgicos beta 2/uso terapéutico , Albuterol/análogos & derivados , Antiasmáticos/uso terapéutico , Asma/diagnóstico , Asma/tratamiento farmacológico , Broncodilatadores/uso terapéutico , Derivados de Escopolamina/uso terapéutico , Adulto , Albuterol/uso terapéutico , Estudios Cruzados , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Xinafoato de Salmeterol , Bromuro de Tiotropio , Resultado del Tratamiento
3.
Scand J Gastroenterol ; 45(7-8): 775-84, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20367197

RESUMEN

The fact that colorectal cancer (CRC) is the second leading cause of cancer mortality in the United States emphasizes the need for more effective preventive and therapeutic modalities. There is growing evidence that vitamin D may reduce the incidence of CRC. Results of epidemiologic, in vitro, in vivo animal and clinical studies suggest that a low serum vitamin D level may be a serious risk factor for CRC and a high serum vitamin D level may reduce the risk of CRC. On a molecular level, vitamin D suppresses CRC development and growth by affecting cell proliferation, differentiation, apoptosis, and angiogenesis. Vitamin D insufficiency and CRC are common in the elderly population. Vitamin D insufficiency is simple to screen for and treatable with vitamin D supplementation. Serum 25-hydroxyvitamin D (calcidiol) is the best measure of vitamin D status and should be checked routinely for individuals with risk factors for CRC. Maintaining serum concentrations of calcidiol above 32 ng/ml (80 nmol/l) in individuals whose serum calcidiol level is low may help prevent CRC as well as osteoporosis, fractures, infections, and cardiovascular disease. Daily calcidiol intake of 1000 International Units can increase serum vitamin D to sufficient levels in most elderly persons and, based on available data, may substantially lower the incidence of CRC with minimal risks.


Asunto(s)
Neoplasias Colorrectales/prevención & control , Vitamina D/sangre , Neoplasias Colorrectales/sangre , Humanos , Medición de Riesgo , Factores de Riesgo
4.
Plant Physiol ; 148(3): 1267-82, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18790999

RESUMEN

Tailoring carotenoids by plant carotenoid cleavage dioxygenases (CCDs) generates various bioactive apocarotenoids. Recombinant CCD1 has been shown to catalyze symmetrical cleavage of C(40) carotenoid substrates at 9,10 and 9',10' positions. The actual substrate(s) of the enzyme in planta, however, is still unknown. In this study, we have carried out RNA interference (RNAi)-mediated repression of a Medicago truncatula CCD1 gene in hairy roots colonized by the arbuscular mycorrhizal (AM) fungus Glomus intraradices. As a consequence, the normal AM-mediated accumulation of apocarotenoids (C(13) cyclohexenone and C(14) mycorradicin derivatives) was differentially modified. Mycorradicin derivatives were strongly reduced to 3% to 6% of the controls, while the cyclohexenone derivatives were only reduced to 30% to 47%. Concomitantly, a yellow-orange color appeared in RNAi roots. Based on ultraviolet light spectra and mass spectrometry analyses, the new compounds are C(27) apocarotenoic acid derivatives. These metabolic alterations did not lead to major changes in molecular markers of the AM symbiosis, although a moderate shift to more degenerating arbuscules was observed in RNAi roots. The unexpected outcome of the RNAi approach suggests C(27) apocarotenoids as the major substrates of CCD1 in mycorrhizal root cells. Moreover, literature data implicate C(27) apocarotenoid cleavage as the general functional role of CCD1 in planta. A revised scheme of plant carotenoid cleavage in two consecutive steps is proposed, in which CCD1 catalyzes only the second step in the cytosol (C(27)-->C(14)+C(13)), while the first step (C(40)-->C(27)+C(13)) may be catalyzed by CCD7 and/or CCD4 inside plastids.


Asunto(s)
Carotenoides/metabolismo , Dioxigenasas/genética , Genes de Plantas , Medicago truncatula/metabolismo , Raíces de Plantas/enzimología , Interferencia de ARN , Secuencia de Bases , Cromatografía Líquida de Alta Presión , Clonación Molecular , Cartilla de ADN , ADN Complementario , Dioxigenasas/metabolismo , Espectrometría de Masas , Medicago truncatula/genética , Datos de Secuencia Molecular , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
5.
Int J Prosthodont ; 19(2): 162-3, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16602364

RESUMEN

PURPOSE: The aim of the study was to evaluate the clinical performance of Procera Alumina AllCeram crowns (Nobel Biocare). MATERIALS AND METHODS: In 70 patients, 61 anterior and 46 posterior teeth were provided with single crowns and cemented with a glass-ionomer cement. RESULTS: Four patients were lost to follow-up. Six crowns had to be removed, all because of nonreparable fracture. At 6 years, the cumulative survival rate was 94.3% for all crowns, 96.7% for anterior crowns, and 91.3% for posterior crowns (survival = not removed). Most of the defects occurred within the first 1.5 years. CONCLUSION: The findings indicate a good clinical prognosis of both anterior and posterior Procera Alumina crowns.


Asunto(s)
Óxido de Aluminio , Coronas , Porcelana Dental , Adulto , Cementación , Fracaso de la Restauración Dental , Femenino , Cementos de Ionómero Vítreo , Humanos , Óxido de Magnesio , Masculino , Cemento de Policarboxilato , Análisis de Supervivencia , Óxido de Zinc
6.
Plant J ; 40(3): 428-38, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15469500

RESUMEN

Dynamic networks of protein-protein interactions regulate numerous cellular processes and determine the ability to respond appropriately to environmental stimuli. However, the investigation of protein complex formation in living plant cells by methods such as fluorescence resonance energy transfer has remained experimentally difficult, time consuming and requires sophisticated technical equipment. Here, we report the implementation of a bimolecular fluorescence complementation (BiFC) technique for visualization of protein-protein interactions in plant cells. This approach relies on the formation of a fluorescent complex by two non-fluorescent fragments of the yellow fluorescent protein brought together by association of interacting proteins fused to these fragments (Hu et al., 2002). To enable BiFC analyses in plant cells, we generated different complementary sets of expression vectors, which enable protein interaction studies in transiently or stably transformed cells. These vectors were used to investigate and visualize homodimerization of the basic leucine zipper (bZIP) transcription factor bZIP63 and the zinc finger protein lesion simulating disease 1 (LSD1) from Arabidopsis as well as the dimer formation of the tobacco 14-3-3 protein T14-3c. The interaction analyses of these model proteins established the feasibility of BiFC analyses for efficient visualization of structurally distinct proteins in different cellular compartments. Our investigations revealed a remarkable signal fluorescence intensity of interacting protein complexes as well as a high reproducibility and technical simplicity of the method in different plant systems. Consequently, the BiFC approach should significantly facilitate the visualization of the subcellular sites of protein interactions under conditions that closely reflect the normal physiological environment.


Asunto(s)
Arabidopsis/metabolismo , Nicotiana/metabolismo , Proteínas de Plantas/metabolismo , Espectrometría de Fluorescencia/métodos , Proteínas de Arabidopsis/metabolismo , Proteínas Bacterianas , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico , Citoplasma/metabolismo , Proteínas de Unión al ADN/metabolismo , Regulación de la Expresión Génica de las Plantas , Proteínas Luminiscentes , Unión Proteica , Multimerización de Proteína , Sensibilidad y Especificidad , Factores de Transcripción/metabolismo
7.
Plant Physiol ; 134(2): 614-24, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14764905

RESUMEN

Colonization of plant roots by symbiotic arbuscular mycorrhizal fungi frequently leads to the accumulation of several apocarotenoids. The corresponding carotenoid precursors originate from the plastidial 2-C-methyl-d-erythritol 4-phosphate pathway. We have cloned and characterized 1-deoxy-d-xylulose 5-phosphate reductoisomerase (DXR), catalyzing the first committed step of the pathway, from maize (Zea mays). Functional identification was accomplished by heterologous expression of sequences coding for the mature protein in Escherichia coli. DXR is up-regulated in maize roots during mycorrhization as shown at transcript and protein levels, but is also abundant in leaves and young seedlings. Inspection of sequenced genomes and expressed sequence tag (EST) databases argue for a single-copy DXR gene. Immunolocalization studies in mycorrhizal roots using affinity-purified antibodies revealed a DXR localization in plastids around the main symbiotic structures, the arbuscules. DXR protein accumulation is tightly correlated with arbuscule development. The highest level of DXR protein is reached around maturity and initial senescence of these structures. We further demonstrate the formation of a DXR-containing plastidial network around arbuscules, which is highly interconnected in the mature, functional state of the arbuscules. Our findings imply a functional role of a still unknown nature for the apocarotenoids or their respective carotenoid precursors in the arbuscular life cycle.


Asunto(s)
Isomerasas Aldosa-Cetosa/genética , Complejos Multienzimáticos/genética , Micorrizas/crecimiento & desarrollo , Oxidorreductasas/genética , Zea mays/enzimología , Isomerasas Aldosa-Cetosa/metabolismo , Clonación Molecular , ADN Complementario/química , ADN Complementario/genética , Regulación Enzimológica de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Inmunohistoquímica , Microscopía Confocal , Datos de Secuencia Molecular , Complejos Multienzimáticos/metabolismo , Oxidorreductasas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raíces de Plantas/enzimología , Raíces de Plantas/genética , Raíces de Plantas/microbiología , Análisis de Secuencia de ADN , Simbiosis/genética , Simbiosis/fisiología , Zea mays/genética , Zea mays/microbiología
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